74372d65ae
Co-authored-by: Andy Locascio <andy@slack-corp.com>
1858 lines
57 KiB
Markdown
1858 lines
57 KiB
Markdown
# webContents
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> Render and control web pages.
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Process: [Main](../glossary.md#main-process)
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`webContents` is an [EventEmitter][event-emitter].
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It is responsible for rendering and controlling a web page and is a property of
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the [`BrowserWindow`](browser-window.md) object. An example of accessing the
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`webContents` object:
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```javascript
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const { BrowserWindow } = require('electron')
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let win = new BrowserWindow({ width: 800, height: 1500 })
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win.loadURL('http://github.com')
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let contents = win.webContents
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console.log(contents)
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```
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## Methods
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These methods can be accessed from the `webContents` module:
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```javascript
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const { webContents } = require('electron')
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console.log(webContents)
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```
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### `webContents.getAllWebContents()`
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Returns `WebContents[]` - An array of all `WebContents` instances. This will contain web contents
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for all windows, webviews, opened devtools, and devtools extension background pages.
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### `webContents.getFocusedWebContents()`
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Returns `WebContents` - The web contents that is focused in this application, otherwise
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returns `null`.
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### `webContents.fromId(id)`
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* `id` Integer
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Returns `WebContents` - A WebContents instance with the given ID.
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## Class: WebContents
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> Render and control the contents of a BrowserWindow instance.
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Process: [Main](../glossary.md#main-process)
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### Instance Events
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#### Event: 'did-finish-load'
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Emitted when the navigation is done, i.e. the spinner of the tab has stopped
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spinning, and the `onload` event was dispatched.
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#### Event: 'did-fail-load'
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Returns:
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* `event` Event
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* `errorCode` Integer
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* `errorDescription` String
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* `validatedURL` String
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* `isMainFrame` Boolean
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* `frameProcessId` Integer
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* `frameRoutingId` Integer
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This event is like `did-finish-load` but emitted when the load failed.
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The full list of error codes and their meaning is available [here](https://code.google.com/p/chromium/codesearch#chromium/src/net/base/net_error_list.h).
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#### Event: 'did-fail-provisional-load'
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Returns:
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* `event` Event
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* `errorCode` Integer
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* `errorDescription` String
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* `validatedURL` String
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* `isMainFrame` Boolean
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* `frameProcessId` Integer
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* `frameRoutingId` Integer
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This event is like `did-fail-load` but emitted when the load was cancelled
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(e.g. `window.stop()` was invoked).
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#### Event: 'did-frame-finish-load'
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Returns:
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* `event` Event
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* `isMainFrame` Boolean
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* `frameProcessId` Integer
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* `frameRoutingId` Integer
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Emitted when a frame has done navigation.
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#### Event: 'did-start-loading'
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Corresponds to the points in time when the spinner of the tab started spinning.
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#### Event: 'did-stop-loading'
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Corresponds to the points in time when the spinner of the tab stopped spinning.
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#### Event: 'dom-ready'
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Returns:
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* `event` Event
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Emitted when the document in the given frame is loaded.
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#### Event: 'page-title-updated'
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Returns:
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* `event` Event
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* `title` String
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* `explicitSet` Boolean
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Fired when page title is set during navigation. `explicitSet` is false when
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title is synthesized from file url.
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#### Event: 'page-favicon-updated'
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Returns:
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* `event` Event
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* `favicons` String[] - Array of URLs.
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Emitted when page receives favicon urls.
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#### Event: 'new-window'
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Returns:
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* `event` Event
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* `url` String
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* `frameName` String
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* `disposition` String - Can be `default`, `foreground-tab`, `background-tab`,
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`new-window`, `save-to-disk` and `other`.
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* `options` BrowserWindowConstructorOptions - The options which will be used for creating the new
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[`BrowserWindow`](browser-window.md).
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* `additionalFeatures` String[] - The non-standard features (features not handled
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by Chromium or Electron) given to `window.open()`.
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* `referrer` [Referrer](structures/referrer.md) - The referrer that will be
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passed to the new window. May or may not result in the `Referer` header being
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sent, depending on the referrer policy.
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* `postBody` [PostBody](structures/post-body.md) (optional) - The post data that
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will be sent to the new window, along with the appropriate headers that will
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be set. If no post data is to be sent, the value will be `null`. Only defined
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when the window is being created by a form that set `target=_blank`.
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Emitted when the page requests to open a new window for a `url`. It could be
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requested by `window.open` or an external link like `<a target='_blank'>`.
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By default a new `BrowserWindow` will be created for the `url`.
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Calling `event.preventDefault()` will prevent Electron from automatically creating a
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new [`BrowserWindow`](browser-window.md). If you call `event.preventDefault()` and manually create a new
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[`BrowserWindow`](browser-window.md) then you must set `event.newGuest` to reference the new [`BrowserWindow`](browser-window.md)
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instance, failing to do so may result in unexpected behavior. For example:
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```javascript
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myBrowserWindow.webContents.on('new-window', (event, url, frameName, disposition, options, additionalFeatures, referrer, postBody) => {
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event.preventDefault()
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const win = new BrowserWindow({
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webContents: options.webContents, // use existing webContents if provided
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show: false
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})
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win.once('ready-to-show', () => win.show())
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if (!options.webContents) {
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const loadOptions = {
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httpReferrer: referrer
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}
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if (postBody != null) {
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const { data, contentType, boundary } = postBody
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loadOptions.postData = postBody.data
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loadOptions.extraHeaders = `content-type: ${contentType}; boundary=${boundary}`
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}
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win.loadURL(url, loadOptions) // existing webContents will be navigated automatically
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}
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event.newGuest = win
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})
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```
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#### Event: 'will-navigate'
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Returns:
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* `event` Event
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* `url` String
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Emitted when a user or the page wants to start navigation. It can happen when
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the `window.location` object is changed or a user clicks a link in the page.
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This event will not emit when the navigation is started programmatically with
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APIs like `webContents.loadURL` and `webContents.back`.
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It is also not emitted for in-page navigations, such as clicking anchor links
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or updating the `window.location.hash`. Use `did-navigate-in-page` event for
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this purpose.
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Calling `event.preventDefault()` will prevent the navigation.
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#### Event: 'did-start-navigation'
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Returns:
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* `event` Event
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* `url` String
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* `isInPlace` Boolean
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* `isMainFrame` Boolean
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* `frameProcessId` Integer
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* `frameRoutingId` Integer
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Emitted when any frame (including main) starts navigating. `isInplace` will be
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`true` for in-page navigations.
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#### Event: 'will-redirect'
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Returns:
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* `event` Event
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* `url` String
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* `isInPlace` Boolean
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* `isMainFrame` Boolean
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* `frameProcessId` Integer
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* `frameRoutingId` Integer
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Emitted as a server side redirect occurs during navigation. For example a 302
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redirect.
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This event will be emitted after `did-start-navigation` and always before the
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`did-redirect-navigation` event for the same navigation.
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Calling `event.preventDefault()` will prevent the navigation (not just the
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redirect).
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#### Event: 'did-redirect-navigation'
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Returns:
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* `event` Event
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* `url` String
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* `isInPlace` Boolean
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* `isMainFrame` Boolean
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* `frameProcessId` Integer
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* `frameRoutingId` Integer
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Emitted after a server side redirect occurs during navigation. For example a 302
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redirect.
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This event can not be prevented, if you want to prevent redirects you should
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checkout out the `will-redirect` event above.
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#### Event: 'did-navigate'
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Returns:
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* `event` Event
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* `url` String
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* `httpResponseCode` Integer - -1 for non HTTP navigations
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* `httpStatusText` String - empty for non HTTP navigations
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Emitted when a main frame navigation is done.
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This event is not emitted for in-page navigations, such as clicking anchor links
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or updating the `window.location.hash`. Use `did-navigate-in-page` event for
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this purpose.
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#### Event: 'did-frame-navigate'
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Returns:
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* `event` Event
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* `url` String
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* `httpResponseCode` Integer - -1 for non HTTP navigations
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* `httpStatusText` String - empty for non HTTP navigations,
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* `isMainFrame` Boolean
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* `frameProcessId` Integer
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* `frameRoutingId` Integer
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Emitted when any frame navigation is done.
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This event is not emitted for in-page navigations, such as clicking anchor links
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or updating the `window.location.hash`. Use `did-navigate-in-page` event for
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this purpose.
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#### Event: 'did-navigate-in-page'
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Returns:
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* `event` Event
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* `url` String
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* `isMainFrame` Boolean
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* `frameProcessId` Integer
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* `frameRoutingId` Integer
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Emitted when an in-page navigation happened in any frame.
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When in-page navigation happens, the page URL changes but does not cause
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navigation outside of the page. Examples of this occurring are when anchor links
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are clicked or when the DOM `hashchange` event is triggered.
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#### Event: 'will-prevent-unload'
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Returns:
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* `event` Event
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Emitted when a `beforeunload` event handler is attempting to cancel a page unload.
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Calling `event.preventDefault()` will ignore the `beforeunload` event handler
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and allow the page to be unloaded.
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```javascript
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const { BrowserWindow, dialog } = require('electron')
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const win = new BrowserWindow({ width: 800, height: 600 })
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win.webContents.on('will-prevent-unload', (event) => {
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const choice = dialog.showMessageBoxSync(win, {
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type: 'question',
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buttons: ['Leave', 'Stay'],
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title: 'Do you want to leave this site?',
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message: 'Changes you made may not be saved.',
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defaultId: 0,
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cancelId: 1
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})
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const leave = (choice === 0)
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if (leave) {
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event.preventDefault()
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}
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})
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```
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#### Event: 'crashed'
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Returns:
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* `event` Event
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* `killed` Boolean
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Emitted when the renderer process crashes or is killed.
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#### Event: 'unresponsive'
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Emitted when the web page becomes unresponsive.
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#### Event: 'responsive'
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Emitted when the unresponsive web page becomes responsive again.
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#### Event: 'plugin-crashed'
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Returns:
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* `event` Event
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* `name` String
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* `version` String
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Emitted when a plugin process has crashed.
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#### Event: 'destroyed'
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Emitted when `webContents` is destroyed.
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#### Event: 'before-input-event'
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Returns:
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* `event` Event
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* `input` Object - Input properties.
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* `type` String - Either `keyUp` or `keyDown`.
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* `key` String - Equivalent to [KeyboardEvent.key][keyboardevent].
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* `code` String - Equivalent to [KeyboardEvent.code][keyboardevent].
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* `isAutoRepeat` Boolean - Equivalent to [KeyboardEvent.repeat][keyboardevent].
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* `shift` Boolean - Equivalent to [KeyboardEvent.shiftKey][keyboardevent].
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* `control` Boolean - Equivalent to [KeyboardEvent.controlKey][keyboardevent].
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* `alt` Boolean - Equivalent to [KeyboardEvent.altKey][keyboardevent].
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* `meta` Boolean - Equivalent to [KeyboardEvent.metaKey][keyboardevent].
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Emitted before dispatching the `keydown` and `keyup` events in the page.
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Calling `event.preventDefault` will prevent the page `keydown`/`keyup` events
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and the menu shortcuts.
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To only prevent the menu shortcuts, use
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[`setIgnoreMenuShortcuts`](#contentssetignoremenushortcutsignore-experimental):
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```javascript
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const { BrowserWindow } = require('electron')
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let win = new BrowserWindow({ width: 800, height: 600 })
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win.webContents.on('before-input-event', (event, input) => {
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// For example, only enable application menu keyboard shortcuts when
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// Ctrl/Cmd are down.
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win.webContents.setIgnoreMenuShortcuts(!input.control && !input.meta)
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})
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```
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#### Event: 'enter-html-full-screen'
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Emitted when the window enters a full-screen state triggered by HTML API.
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#### Event: 'leave-html-full-screen'
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Emitted when the window leaves a full-screen state triggered by HTML API.
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#### Event: 'zoom-changed'
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Returns:
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* `event` Event
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* `zoomDirection` String - Can be `in` or `out`.
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Emitted when the user is requesting to change the zoom level using the mouse wheel.
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#### Event: 'devtools-opened'
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Emitted when DevTools is opened.
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#### Event: 'devtools-closed'
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Emitted when DevTools is closed.
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#### Event: 'devtools-focused'
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Emitted when DevTools is focused / opened.
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#### Event: 'certificate-error'
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Returns:
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* `event` Event
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* `url` String
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* `error` String - The error code.
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* `certificate` [Certificate](structures/certificate.md)
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* `callback` Function
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* `isTrusted` Boolean - Indicates whether the certificate can be considered trusted.
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Emitted when failed to verify the `certificate` for `url`.
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The usage is the same with [the `certificate-error` event of
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`app`](app.md#event-certificate-error).
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#### Event: 'select-client-certificate'
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Returns:
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* `event` Event
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* `url` URL
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* `certificateList` [Certificate[]](structures/certificate.md)
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* `callback` Function
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* `certificate` [Certificate](structures/certificate.md) - Must be a certificate from the given list.
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Emitted when a client certificate is requested.
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The usage is the same with [the `select-client-certificate` event of
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`app`](app.md#event-select-client-certificate).
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#### Event: 'login'
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Returns:
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* `event` Event
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* `authenticationResponseDetails` Object
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* `url` URL
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* `authInfo` Object
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* `isProxy` Boolean
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* `scheme` String
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* `host` String
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* `port` Integer
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* `realm` String
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* `callback` Function
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* `username` String (optional)
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* `password` String (optional)
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Emitted when `webContents` wants to do basic auth.
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The usage is the same with [the `login` event of `app`](app.md#event-login).
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#### Event: 'found-in-page'
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Returns:
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* `event` Event
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* `result` Object
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* `requestId` Integer
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* `activeMatchOrdinal` Integer - Position of the active match.
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* `matches` Integer - Number of Matches.
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* `selectionArea` Rectangle - Coordinates of first match region.
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* `finalUpdate` Boolean
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Emitted when a result is available for
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[`webContents.findInPage`] request.
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#### Event: 'media-started-playing'
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Emitted when media starts playing.
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#### Event: 'media-paused'
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Emitted when media is paused or done playing.
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#### Event: 'did-change-theme-color'
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Returns:
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* `event` Event
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* `color` (String | null) - Theme color is in format of '#rrggbb'. It is `null` when no theme color is set.
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Emitted when a page's theme color changes. This is usually due to encountering
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a meta tag:
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```html
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<meta name='theme-color' content='#ff0000'>
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```
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#### Event: 'update-target-url'
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Returns:
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* `event` Event
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* `url` String
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Emitted when mouse moves over a link or the keyboard moves the focus to a link.
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#### Event: 'cursor-changed'
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Returns:
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* `event` Event
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* `type` String
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* `image` [NativeImage](native-image.md) (optional)
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* `scale` Float (optional) - scaling factor for the custom cursor.
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* `size` [Size](structures/size.md) (optional) - the size of the `image`.
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* `hotspot` [Point](structures/point.md) (optional) - coordinates of the custom cursor's hotspot.
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Emitted when the cursor's type changes. The `type` parameter can be `default`,
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`crosshair`, `pointer`, `text`, `wait`, `help`, `e-resize`, `n-resize`,
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`ne-resize`, `nw-resize`, `s-resize`, `se-resize`, `sw-resize`, `w-resize`,
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`ns-resize`, `ew-resize`, `nesw-resize`, `nwse-resize`, `col-resize`,
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`row-resize`, `m-panning`, `e-panning`, `n-panning`, `ne-panning`, `nw-panning`,
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`s-panning`, `se-panning`, `sw-panning`, `w-panning`, `move`, `vertical-text`,
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`cell`, `context-menu`, `alias`, `progress`, `nodrop`, `copy`, `none`,
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`not-allowed`, `zoom-in`, `zoom-out`, `grab`, `grabbing` or `custom`.
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If the `type` parameter is `custom`, the `image` parameter will hold the custom
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cursor image in a [`NativeImage`](native-image.md), and `scale`, `size` and `hotspot` will hold
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additional information about the custom cursor.
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#### Event: 'context-menu'
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Returns:
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* `event` Event
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|
* `params` Object
|
|
* `x` Integer - x coordinate.
|
|
* `y` Integer - y coordinate.
|
|
* `linkURL` String - URL of the link that encloses the node the context menu
|
|
was invoked on.
|
|
* `linkText` String - Text associated with the link. May be an empty
|
|
string if the contents of the link are an image.
|
|
* `pageURL` String - URL of the top level page that the context menu was
|
|
invoked on.
|
|
* `frameURL` String - URL of the subframe that the context menu was invoked
|
|
on.
|
|
* `srcURL` String - Source URL for the element that the context menu
|
|
was invoked on. Elements with source URLs are images, audio and video.
|
|
* `mediaType` String - Type of the node the context menu was invoked on. Can
|
|
be `none`, `image`, `audio`, `video`, `canvas`, `file` or `plugin`.
|
|
* `hasImageContents` Boolean - Whether the context menu was invoked on an image
|
|
which has non-empty contents.
|
|
* `isEditable` Boolean - Whether the context is editable.
|
|
* `selectionText` String - Text of the selection that the context menu was
|
|
invoked on.
|
|
* `titleText` String - Title or alt text of the selection that the context
|
|
was invoked on.
|
|
* `misspelledWord` String - The misspelled word under the cursor, if any.
|
|
* `dictionarySuggestions` String[] - An array of suggested words to show the
|
|
user to replace the `misspelledWord`. Only available if there is a misspelled
|
|
word and spellchecker is enabled.
|
|
* `frameCharset` String - The character encoding of the frame on which the
|
|
menu was invoked.
|
|
* `inputFieldType` String - If the context menu was invoked on an input
|
|
field, the type of that field. Possible values are `none`, `plainText`,
|
|
`password`, `other`.
|
|
* `menuSourceType` String - Input source that invoked the context menu.
|
|
Can be `none`, `mouse`, `keyboard`, `touch` or `touchMenu`.
|
|
* `mediaFlags` Object - The flags for the media element the context menu was
|
|
invoked on.
|
|
* `inError` Boolean - Whether the media element has crashed.
|
|
* `isPaused` Boolean - Whether the media element is paused.
|
|
* `isMuted` Boolean - Whether the media element is muted.
|
|
* `hasAudio` Boolean - Whether the media element has audio.
|
|
* `isLooping` Boolean - Whether the media element is looping.
|
|
* `isControlsVisible` Boolean - Whether the media element's controls are
|
|
visible.
|
|
* `canToggleControls` Boolean - Whether the media element's controls are
|
|
toggleable.
|
|
* `canRotate` Boolean - Whether the media element can be rotated.
|
|
* `editFlags` Object - These flags indicate whether the renderer believes it
|
|
is able to perform the corresponding action.
|
|
* `canUndo` Boolean - Whether the renderer believes it can undo.
|
|
* `canRedo` Boolean - Whether the renderer believes it can redo.
|
|
* `canCut` Boolean - Whether the renderer believes it can cut.
|
|
* `canCopy` Boolean - Whether the renderer believes it can copy
|
|
* `canPaste` Boolean - Whether the renderer believes it can paste.
|
|
* `canDelete` Boolean - Whether the renderer believes it can delete.
|
|
* `canSelectAll` Boolean - Whether the renderer believes it can select all.
|
|
|
|
Emitted when there is a new context menu that needs to be handled.
|
|
|
|
#### Event: 'select-bluetooth-device'
|
|
|
|
Returns:
|
|
|
|
* `event` Event
|
|
* `devices` [BluetoothDevice[]](structures/bluetooth-device.md)
|
|
* `callback` Function
|
|
* `deviceId` String
|
|
|
|
Emitted when bluetooth device needs to be selected on call to
|
|
`navigator.bluetooth.requestDevice`. To use `navigator.bluetooth` api
|
|
`webBluetooth` should be enabled. If `event.preventDefault` is not called,
|
|
first available device will be selected. `callback` should be called with
|
|
`deviceId` to be selected, passing empty string to `callback` will
|
|
cancel the request.
|
|
|
|
```javascript
|
|
const { app, BrowserWindow } = require('electron')
|
|
|
|
let win = null
|
|
app.commandLine.appendSwitch('enable-experimental-web-platform-features')
|
|
|
|
app.whenReady().then(() => {
|
|
win = new BrowserWindow({ width: 800, height: 600 })
|
|
win.webContents.on('select-bluetooth-device', (event, deviceList, callback) => {
|
|
event.preventDefault()
|
|
let result = deviceList.find((device) => {
|
|
return device.deviceName === 'test'
|
|
})
|
|
if (!result) {
|
|
callback('')
|
|
} else {
|
|
callback(result.deviceId)
|
|
}
|
|
})
|
|
})
|
|
```
|
|
|
|
#### Event: 'paint'
|
|
|
|
Returns:
|
|
|
|
* `event` Event
|
|
* `dirtyRect` [Rectangle](structures/rectangle.md)
|
|
* `image` [NativeImage](native-image.md) - The image data of the whole frame.
|
|
|
|
Emitted when a new frame is generated. Only the dirty area is passed in the
|
|
buffer.
|
|
|
|
```javascript
|
|
const { BrowserWindow } = require('electron')
|
|
|
|
let win = new BrowserWindow({ webPreferences: { offscreen: true } })
|
|
win.webContents.on('paint', (event, dirty, image) => {
|
|
// updateBitmap(dirty, image.getBitmap())
|
|
})
|
|
win.loadURL('http://github.com')
|
|
```
|
|
|
|
#### Event: 'devtools-reload-page'
|
|
|
|
Emitted when the devtools window instructs the webContents to reload
|
|
|
|
#### Event: 'will-attach-webview'
|
|
|
|
Returns:
|
|
|
|
* `event` Event
|
|
* `webPreferences` WebPreferences - The web preferences that will be used by the guest
|
|
page. This object can be modified to adjust the preferences for the guest
|
|
page.
|
|
* `params` Record<string, string> - The other `<webview>` parameters such as the `src` URL.
|
|
This object can be modified to adjust the parameters of the guest page.
|
|
|
|
Emitted when a `<webview>`'s web contents is being attached to this web
|
|
contents. Calling `event.preventDefault()` will destroy the guest page.
|
|
|
|
This event can be used to configure `webPreferences` for the `webContents`
|
|
of a `<webview>` before it's loaded, and provides the ability to set settings
|
|
that can't be set via `<webview>` attributes.
|
|
|
|
**Note:** The specified `preload` script option will be appear as `preloadURL`
|
|
(not `preload`) in the `webPreferences` object emitted with this event.
|
|
|
|
#### Event: 'did-attach-webview'
|
|
|
|
Returns:
|
|
|
|
* `event` Event
|
|
* `webContents` WebContents - The guest web contents that is used by the
|
|
`<webview>`.
|
|
|
|
Emitted when a `<webview>` has been attached to this web contents.
|
|
|
|
#### Event: 'console-message'
|
|
|
|
Returns:
|
|
|
|
* `event` Event
|
|
* `level` Integer
|
|
* `message` String
|
|
* `line` Integer
|
|
* `sourceId` String
|
|
|
|
Emitted when the associated window logs a console message.
|
|
|
|
#### Event: 'preload-error'
|
|
|
|
Returns:
|
|
|
|
* `event` Event
|
|
* `preloadPath` String
|
|
* `error` Error
|
|
|
|
Emitted when the preload script `preloadPath` throws an unhandled exception `error`.
|
|
|
|
#### Event: 'ipc-message'
|
|
|
|
Returns:
|
|
|
|
* `event` Event
|
|
* `channel` String
|
|
* `...args` any[]
|
|
|
|
Emitted when the renderer process sends an asynchronous message via `ipcRenderer.send()`.
|
|
|
|
#### Event: 'ipc-message-sync'
|
|
|
|
Returns:
|
|
|
|
* `event` Event
|
|
* `channel` String
|
|
* `...args` any[]
|
|
|
|
Emitted when the renderer process sends a synchronous message via `ipcRenderer.sendSync()`.
|
|
|
|
#### Event: 'desktop-capturer-get-sources'
|
|
|
|
Returns:
|
|
|
|
* `event` Event
|
|
|
|
Emitted when `desktopCapturer.getSources()` is called in the renderer process.
|
|
Calling `event.preventDefault()` will make it return empty sources.
|
|
|
|
#### Event: 'remote-require'
|
|
|
|
Returns:
|
|
|
|
* `event` IpcMainEvent
|
|
* `moduleName` String
|
|
|
|
Emitted when `remote.require()` is called in the renderer process.
|
|
Calling `event.preventDefault()` will prevent the module from being returned.
|
|
Custom value can be returned by setting `event.returnValue`.
|
|
|
|
#### Event: 'remote-get-global'
|
|
|
|
Returns:
|
|
|
|
* `event` IpcMainEvent
|
|
* `globalName` String
|
|
|
|
Emitted when `remote.getGlobal()` is called in the renderer process.
|
|
Calling `event.preventDefault()` will prevent the global from being returned.
|
|
Custom value can be returned by setting `event.returnValue`.
|
|
|
|
#### Event: 'remote-get-builtin'
|
|
|
|
Returns:
|
|
|
|
* `event` IpcMainEvent
|
|
* `moduleName` String
|
|
|
|
Emitted when `remote.getBuiltin()` is called in the renderer process.
|
|
Calling `event.preventDefault()` will prevent the module from being returned.
|
|
Custom value can be returned by setting `event.returnValue`.
|
|
|
|
#### Event: 'remote-get-current-window'
|
|
|
|
Returns:
|
|
|
|
* `event` IpcMainEvent
|
|
|
|
Emitted when `remote.getCurrentWindow()` is called in the renderer process.
|
|
Calling `event.preventDefault()` will prevent the object from being returned.
|
|
Custom value can be returned by setting `event.returnValue`.
|
|
|
|
#### Event: 'remote-get-current-web-contents'
|
|
|
|
Returns:
|
|
|
|
* `event` IpcMainEvent
|
|
|
|
Emitted when `remote.getCurrentWebContents()` is called in the renderer process.
|
|
Calling `event.preventDefault()` will prevent the object from being returned.
|
|
Custom value can be returned by setting `event.returnValue`.
|
|
|
|
### Instance Methods
|
|
|
|
#### `contents.loadURL(url[, options])`
|
|
|
|
* `url` String
|
|
* `options` Object (optional)
|
|
* `httpReferrer` (String | [Referrer](structures/referrer.md)) (optional) - An HTTP Referrer url.
|
|
* `userAgent` String (optional) - A user agent originating the request.
|
|
* `extraHeaders` String (optional) - Extra headers separated by "\n".
|
|
* `postData` ([UploadRawData[]](structures/upload-raw-data.md) | [UploadFile[]](structures/upload-file.md) | [UploadBlob[]](structures/upload-blob.md)) (optional)
|
|
* `baseURLForDataURL` String (optional) - Base url (with trailing path separator) for files to be loaded by the data url. This is needed only if the specified `url` is a data url and needs to load other files.
|
|
|
|
Returns `Promise<void>` - the promise will resolve when the page has finished loading
|
|
(see [`did-finish-load`](web-contents.md#event-did-finish-load)), and rejects
|
|
if the page fails to load (see
|
|
[`did-fail-load`](web-contents.md#event-did-fail-load)). A noop rejection handler is already attached, which avoids unhandled rejection errors.
|
|
|
|
Loads the `url` in the window. The `url` must contain the protocol prefix,
|
|
e.g. the `http://` or `file://`. If the load should bypass http cache then
|
|
use the `pragma` header to achieve it.
|
|
|
|
```javascript
|
|
const { webContents } = require('electron')
|
|
const options = { extraHeaders: 'pragma: no-cache\n' }
|
|
webContents.loadURL('https://github.com', options)
|
|
```
|
|
|
|
#### `contents.loadFile(filePath[, options])`
|
|
|
|
* `filePath` String
|
|
* `options` Object (optional)
|
|
* `query` Record<String, String> (optional) - Passed to `url.format()`.
|
|
* `search` String (optional) - Passed to `url.format()`.
|
|
* `hash` String (optional) - Passed to `url.format()`.
|
|
|
|
Returns `Promise<void>` - the promise will resolve when the page has finished loading
|
|
(see [`did-finish-load`](web-contents.md#event-did-finish-load)), and rejects
|
|
if the page fails to load (see [`did-fail-load`](web-contents.md#event-did-fail-load)).
|
|
|
|
Loads the given file in the window, `filePath` should be a path to
|
|
an HTML file relative to the root of your application. For instance
|
|
an app structure like this:
|
|
|
|
```sh
|
|
| root
|
|
| - package.json
|
|
| - src
|
|
| - main.js
|
|
| - index.html
|
|
```
|
|
|
|
Would require code like this
|
|
|
|
```js
|
|
win.loadFile('src/index.html')
|
|
```
|
|
|
|
#### `contents.downloadURL(url)`
|
|
|
|
* `url` String
|
|
|
|
Initiates a download of the resource at `url` without navigating. The
|
|
`will-download` event of `session` will be triggered.
|
|
|
|
#### `contents.getURL()`
|
|
|
|
Returns `String` - The URL of the current web page.
|
|
|
|
```javascript
|
|
const { BrowserWindow } = require('electron')
|
|
let win = new BrowserWindow({ width: 800, height: 600 })
|
|
win.loadURL('http://github.com')
|
|
|
|
let currentURL = win.webContents.getURL()
|
|
console.log(currentURL)
|
|
```
|
|
|
|
#### `contents.getTitle()`
|
|
|
|
Returns `String` - The title of the current web page.
|
|
|
|
#### `contents.isDestroyed()`
|
|
|
|
Returns `Boolean` - Whether the web page is destroyed.
|
|
|
|
#### `contents.focus()`
|
|
|
|
Focuses the web page.
|
|
|
|
#### `contents.isFocused()`
|
|
|
|
Returns `Boolean` - Whether the web page is focused.
|
|
|
|
#### `contents.isLoading()`
|
|
|
|
Returns `Boolean` - Whether web page is still loading resources.
|
|
|
|
#### `contents.isLoadingMainFrame()`
|
|
|
|
Returns `Boolean` - Whether the main frame (and not just iframes or frames within it) is
|
|
still loading.
|
|
|
|
#### `contents.isWaitingForResponse()`
|
|
|
|
Returns `Boolean` - Whether the web page is waiting for a first-response from the main
|
|
resource of the page.
|
|
|
|
#### `contents.stop()`
|
|
|
|
Stops any pending navigation.
|
|
|
|
#### `contents.reload()`
|
|
|
|
Reloads the current web page.
|
|
|
|
#### `contents.reloadIgnoringCache()`
|
|
|
|
Reloads current page and ignores cache.
|
|
|
|
#### `contents.canGoBack()`
|
|
|
|
Returns `Boolean` - Whether the browser can go back to previous web page.
|
|
|
|
#### `contents.canGoForward()`
|
|
|
|
Returns `Boolean` - Whether the browser can go forward to next web page.
|
|
|
|
#### `contents.canGoToOffset(offset)`
|
|
|
|
* `offset` Integer
|
|
|
|
Returns `Boolean` - Whether the web page can go to `offset`.
|
|
|
|
#### `contents.clearHistory()`
|
|
|
|
Clears the navigation history.
|
|
|
|
#### `contents.goBack()`
|
|
|
|
Makes the browser go back a web page.
|
|
|
|
#### `contents.goForward()`
|
|
|
|
Makes the browser go forward a web page.
|
|
|
|
#### `contents.goToIndex(index)`
|
|
|
|
* `index` Integer
|
|
|
|
Navigates browser to the specified absolute web page index.
|
|
|
|
#### `contents.goToOffset(offset)`
|
|
|
|
* `offset` Integer
|
|
|
|
Navigates to the specified offset from the "current entry".
|
|
|
|
#### `contents.isCrashed()`
|
|
|
|
Returns `Boolean` - Whether the renderer process has crashed.
|
|
|
|
#### `contents.setUserAgent(userAgent)`
|
|
|
|
* `userAgent` String
|
|
|
|
Overrides the user agent for this web page.
|
|
|
|
#### `contents.getUserAgent()`
|
|
|
|
Returns `String` - The user agent for this web page.
|
|
|
|
#### `contents.insertCSS(css[, options])`
|
|
|
|
* `css` String
|
|
* `options` Object (optional)
|
|
* `cssOrigin` String (optional) - Can be either 'user' or 'author'; Specifying 'user' enables you to prevent websites from overriding the CSS you insert. Default is 'author'.
|
|
|
|
Returns `Promise<String>` - A promise that resolves with a key for the inserted CSS that can later be used to remove the CSS via `contents.removeInsertedCSS(key)`.
|
|
|
|
Injects CSS into the current web page and returns a unique key for the inserted
|
|
stylesheet.
|
|
|
|
```js
|
|
contents.on('did-finish-load', () => {
|
|
contents.insertCSS('html, body { background-color: #f00; }')
|
|
})
|
|
```
|
|
|
|
#### `contents.removeInsertedCSS(key)`
|
|
|
|
* `key` String
|
|
|
|
Returns `Promise<void>` - Resolves if the removal was successful.
|
|
|
|
Removes the inserted CSS from the current web page. The stylesheet is identified
|
|
by its key, which is returned from `contents.insertCSS(css)`.
|
|
|
|
```js
|
|
contents.on('did-finish-load', async () => {
|
|
const key = await contents.insertCSS('html, body { background-color: #f00; }')
|
|
contents.removeInsertedCSS(key)
|
|
})
|
|
```
|
|
|
|
#### `contents.executeJavaScript(code[, userGesture])`
|
|
|
|
* `code` String
|
|
* `userGesture` Boolean (optional) - Default is `false`.
|
|
|
|
Returns `Promise<any>` - A promise that resolves with the result of the executed code
|
|
or is rejected if the result of the code is a rejected promise.
|
|
|
|
Evaluates `code` in page.
|
|
|
|
In the browser window some HTML APIs like `requestFullScreen` can only be
|
|
invoked by a gesture from the user. Setting `userGesture` to `true` will remove
|
|
this limitation.
|
|
|
|
Code execution will be suspended until web page stop loading.
|
|
|
|
```js
|
|
contents.executeJavaScript('fetch("https://jsonplaceholder.typicode.com/users/1").then(resp => resp.json())', true)
|
|
.then((result) => {
|
|
console.log(result) // Will be the JSON object from the fetch call
|
|
})
|
|
```
|
|
|
|
#### `contents.executeJavaScriptInIsolatedWorld(worldId, scripts[, userGesture])`
|
|
|
|
* `worldId` Integer - The ID of the world to run the javascript in, `0` is the default world, `999` is the world used by Electron's `contextIsolation` feature. You can provide any integer here.
|
|
* `scripts` [WebSource[]](structures/web-source.md)
|
|
* `userGesture` Boolean (optional) - Default is `false`.
|
|
|
|
Returns `Promise<any>` - A promise that resolves with the result of the executed code
|
|
or is rejected if the result of the code is a rejected promise.
|
|
|
|
Works like `executeJavaScript` but evaluates `scripts` in an isolated context.
|
|
|
|
#### `contents.setIgnoreMenuShortcuts(ignore)` _Experimental_
|
|
|
|
* `ignore` Boolean
|
|
|
|
Ignore application menu shortcuts while this web contents is focused.
|
|
|
|
#### `contents.setAudioMuted(muted)`
|
|
|
|
* `muted` Boolean
|
|
|
|
Mute the audio on the current web page.
|
|
|
|
#### `contents.isAudioMuted()`
|
|
|
|
Returns `Boolean` - Whether this page has been muted.
|
|
|
|
#### `contents.isCurrentlyAudible()`
|
|
|
|
Returns `Boolean` - Whether audio is currently playing.
|
|
|
|
#### `contents.setZoomFactor(factor)`
|
|
|
|
* `factor` Double - Zoom factor; default is 1.0.
|
|
|
|
Changes the zoom factor to the specified factor. Zoom factor is
|
|
zoom percent divided by 100, so 300% = 3.0.
|
|
|
|
The factor must be greater than 0.0.
|
|
|
|
#### `contents.getZoomFactor()`
|
|
|
|
Returns `Number` - the current zoom factor.
|
|
|
|
#### `contents.setZoomLevel(level)`
|
|
|
|
* `level` Number - Zoom level.
|
|
|
|
Changes the zoom level to the specified level. The original size is 0 and each
|
|
increment above or below represents zooming 20% larger or smaller to default
|
|
limits of 300% and 50% of original size, respectively. The formula for this is
|
|
`scale := 1.2 ^ level`.
|
|
|
|
#### `contents.getZoomLevel()`
|
|
|
|
Returns `Number` - the current zoom level.
|
|
|
|
#### `contents.setVisualZoomLevelLimits(minimumLevel, maximumLevel)`
|
|
|
|
* `minimumLevel` Number
|
|
* `maximumLevel` Number
|
|
|
|
Returns `Promise<void>`
|
|
|
|
Sets the maximum and minimum pinch-to-zoom level.
|
|
|
|
> **NOTE**: Visual zoom is disabled by default in Electron. To re-enable it, call:
|
|
>
|
|
> ```js
|
|
> contents.setVisualZoomLevelLimits(1, 3)
|
|
> ```
|
|
|
|
#### `contents.undo()`
|
|
|
|
Executes the editing command `undo` in web page.
|
|
|
|
#### `contents.redo()`
|
|
|
|
Executes the editing command `redo` in web page.
|
|
|
|
#### `contents.cut()`
|
|
|
|
Executes the editing command `cut` in web page.
|
|
|
|
#### `contents.copy()`
|
|
|
|
Executes the editing command `copy` in web page.
|
|
|
|
#### `contents.copyImageAt(x, y)`
|
|
|
|
* `x` Integer
|
|
* `y` Integer
|
|
|
|
Copy the image at the given position to the clipboard.
|
|
|
|
#### `contents.paste()`
|
|
|
|
Executes the editing command `paste` in web page.
|
|
|
|
#### `contents.pasteAndMatchStyle()`
|
|
|
|
Executes the editing command `pasteAndMatchStyle` in web page.
|
|
|
|
#### `contents.delete()`
|
|
|
|
Executes the editing command `delete` in web page.
|
|
|
|
#### `contents.selectAll()`
|
|
|
|
Executes the editing command `selectAll` in web page.
|
|
|
|
#### `contents.unselect()`
|
|
|
|
Executes the editing command `unselect` in web page.
|
|
|
|
#### `contents.replace(text)`
|
|
|
|
* `text` String
|
|
|
|
Executes the editing command `replace` in web page.
|
|
|
|
#### `contents.replaceMisspelling(text)`
|
|
|
|
* `text` String
|
|
|
|
Executes the editing command `replaceMisspelling` in web page.
|
|
|
|
#### `contents.insertText(text)`
|
|
|
|
* `text` String
|
|
|
|
Returns `Promise<void>`
|
|
|
|
Inserts `text` to the focused element.
|
|
|
|
#### `contents.findInPage(text[, options])`
|
|
|
|
* `text` String - Content to be searched, must not be empty.
|
|
* `options` Object (optional)
|
|
* `forward` Boolean (optional) - Whether to search forward or backward, defaults to `true`.
|
|
* `findNext` Boolean (optional) - Whether the operation is first request or a follow up,
|
|
defaults to `false`.
|
|
* `matchCase` Boolean (optional) - Whether search should be case-sensitive,
|
|
defaults to `false`.
|
|
* `wordStart` Boolean (optional) - Whether to look only at the start of words.
|
|
defaults to `false`.
|
|
* `medialCapitalAsWordStart` Boolean (optional) - When combined with `wordStart`,
|
|
accepts a match in the middle of a word if the match begins with an
|
|
uppercase letter followed by a lowercase or non-letter.
|
|
Accepts several other intra-word matches, defaults to `false`.
|
|
|
|
Returns `Integer` - The request id used for the request.
|
|
|
|
Starts a request to find all matches for the `text` in the web page. The result of the request
|
|
can be obtained by subscribing to [`found-in-page`](web-contents.md#event-found-in-page) event.
|
|
|
|
#### `contents.stopFindInPage(action)`
|
|
|
|
* `action` String - Specifies the action to take place when ending
|
|
[`webContents.findInPage`] request.
|
|
* `clearSelection` - Clear the selection.
|
|
* `keepSelection` - Translate the selection into a normal selection.
|
|
* `activateSelection` - Focus and click the selection node.
|
|
|
|
Stops any `findInPage` request for the `webContents` with the provided `action`.
|
|
|
|
```javascript
|
|
const { webContents } = require('electron')
|
|
webContents.on('found-in-page', (event, result) => {
|
|
if (result.finalUpdate) webContents.stopFindInPage('clearSelection')
|
|
})
|
|
|
|
const requestId = webContents.findInPage('api')
|
|
console.log(requestId)
|
|
```
|
|
|
|
#### `contents.capturePage([rect])`
|
|
|
|
* `rect` [Rectangle](structures/rectangle.md) (optional) - The area of the page to be captured.
|
|
|
|
Returns `Promise<NativeImage>` - Resolves with a [NativeImage](native-image.md)
|
|
|
|
Captures a snapshot of the page within `rect`. Omitting `rect` will capture the whole visible page.
|
|
|
|
#### `contents.isBeingCaptured()`
|
|
|
|
Returns `Boolean` - Whether this page is being captured. It returns true when the capturer count
|
|
is large then 0.
|
|
|
|
#### `contents.incrementCapturerCount([size, stayHidden])`
|
|
|
|
* `size` [Size](structures/size.md) (optional) - The perferred size for the capturer.
|
|
* `stayHidden` Boolean (optional) - Keep the page hidden instead of visible.
|
|
|
|
Increase the capturer count by one. The page is considered visible when its browser window is
|
|
hidden and the capturer count is non-zero. If you would like the page to stay hidden, you should ensure that `stayHidden` is set to true.
|
|
|
|
This also affects the Page Visibility API.
|
|
|
|
#### `contents.decrementCapturerCount([stayHidden])`
|
|
|
|
* `stayHidden` Boolean (optional) - Keep the page in hidden state instead of visible.
|
|
|
|
Decrease the capturer count by one. The page will be set to hidden or occluded state when its
|
|
browser window is hidden or occluded and the capturer count reaches zero. If you want to
|
|
decrease the hidden capturer count instead you should set `stayHidden` to true.
|
|
|
|
#### `contents.getPrinters()`
|
|
|
|
Get the system printer list.
|
|
|
|
Returns [`PrinterInfo[]`](structures/printer-info.md)
|
|
|
|
#### `contents.print([options], [callback])`
|
|
|
|
* `options` Object (optional)
|
|
* `silent` Boolean (optional) - Don't ask user for print settings. Default is `false`.
|
|
* `printBackground` Boolean (optional) - Prints the background color and image of
|
|
the web page. Default is `false`.
|
|
* `deviceName` String (optional) - Set the printer device name to use. Must be the system-defined name and not the 'friendly' name, e.g 'Brother_QL_820NWB' and not 'Brother QL-820NWB'.
|
|
* `color` Boolean (optional) - Set whether the printed web page will be in color or grayscale. Default is `true`.
|
|
* `margins` Object (optional)
|
|
* `marginType` String (optional) - Can be `default`, `none`, `printableArea`, or `custom`. If `custom` is chosen, you will also need to specify `top`, `bottom`, `left`, and `right`.
|
|
* `top` Number (optional) - The top margin of the printed web page, in pixels.
|
|
* `bottom` Number (optional) - The bottom margin of the printed web page, in pixels.
|
|
* `left` Number (optional) - The left margin of the printed web page, in pixels.
|
|
* `right` Number (optional) - The right margin of the printed web page, in pixels.
|
|
* `landscape` Boolean (optional) - Whether the web page should be printed in landscape mode. Default is `false`.
|
|
* `scaleFactor` Number (optional) - The scale factor of the web page.
|
|
* `pagesPerSheet` Number (optional) - The number of pages to print per page sheet.
|
|
* `collate` Boolean (optional) - Whether the web page should be collated.
|
|
* `copies` Number (optional) - The number of copies of the web page to print.
|
|
* `pageRanges` Record<string, number> (optional) - The page range to print.
|
|
* `from` Number - the start page.
|
|
* `to` Number - the end page.
|
|
* `duplexMode` String (optional) - Set the duplex mode of the printed web page. Can be `simplex`, `shortEdge`, or `longEdge`.
|
|
* `dpi` Record<string, number> (optional)
|
|
* `horizontal` Number (optional) - The horizontal dpi.
|
|
* `vertical` Number (optional) - The vertical dpi.
|
|
* `header` String (optional) - String to be printed as page header.
|
|
* `footer` String (optional) - String to be printed as page footer.
|
|
* `pageSize` String | Size (optional) - Specify page size of the printed document. Can be `A3`,
|
|
`A4`, `A5`, `Legal`, `Letter`, `Tabloid` or an Object containing `height`.
|
|
* `callback` Function (optional)
|
|
* `success` Boolean - Indicates success of the print call.
|
|
* `failureReason` String - Error description called back if the print fails.
|
|
|
|
Prints window's web page. When `silent` is set to `true`, Electron will pick
|
|
the system's default printer if `deviceName` is empty and the default settings for printing.
|
|
|
|
Use `page-break-before: always;` CSS style to force to print to a new page.
|
|
|
|
Example usage:
|
|
|
|
```js
|
|
const options = { silent: true, deviceName: 'My-Printer' }
|
|
win.webContents.print(options, (success, errorType) => {
|
|
if (!success) console.log(errorType)
|
|
})
|
|
```
|
|
|
|
#### `contents.printToPDF(options)`
|
|
|
|
* `options` Object
|
|
* `headerFooter` Record<string, string> (optional) - the header and footer for the PDF.
|
|
* `title` String - The title for the PDF header.
|
|
* `url` String - the url for the PDF footer.
|
|
* `landscape` Boolean (optional) - `true` for landscape, `false` for portrait.
|
|
* `marginsType` Integer (optional) - Specifies the type of margins to use. Uses 0 for
|
|
default margin, 1 for no margin, and 2 for minimum margin.
|
|
and `width` in microns.
|
|
* `scaleFactor` Number (optional) - The scale factor of the web page. Can range from 0 to 100.
|
|
* `pageRanges` Record<string, number> (optional) - The page range to print.
|
|
* `from` Number - the first page to print.
|
|
* `to` Number - the last page to print (inclusive).
|
|
* `pageSize` String | Size (optional) - Specify page size of the generated PDF. Can be `A3`,
|
|
`A4`, `A5`, `Legal`, `Letter`, `Tabloid` or an Object containing `height`
|
|
* `printBackground` Boolean (optional) - Whether to print CSS backgrounds.
|
|
* `printSelectionOnly` Boolean (optional) - Whether to print selection only.
|
|
|
|
Returns `Promise<Buffer>` - Resolves with the generated PDF data.
|
|
|
|
Prints window's web page as PDF with Chromium's preview printing custom
|
|
settings.
|
|
|
|
The `landscape` will be ignored if `@page` CSS at-rule is used in the web page.
|
|
|
|
By default, an empty `options` will be regarded as:
|
|
|
|
```javascript
|
|
{
|
|
marginsType: 0,
|
|
printBackground: false,
|
|
printSelectionOnly: false,
|
|
landscape: false,
|
|
pageSize: 'A4',
|
|
scaleFactor: 100
|
|
}
|
|
```
|
|
|
|
Use `page-break-before: always; ` CSS style to force to print to a new page.
|
|
|
|
An example of `webContents.printToPDF`:
|
|
|
|
```javascript
|
|
const { BrowserWindow } = require('electron')
|
|
const fs = require('fs')
|
|
|
|
let win = new BrowserWindow({ width: 800, height: 600 })
|
|
win.loadURL('http://github.com')
|
|
|
|
win.webContents.on('did-finish-load', () => {
|
|
// Use default printing options
|
|
win.webContents.printToPDF({}).then(data => {
|
|
fs.writeFile('/tmp/print.pdf', data, (error) => {
|
|
if (error) throw error
|
|
console.log('Write PDF successfully.')
|
|
})
|
|
}).catch(error => {
|
|
console.log(error)
|
|
})
|
|
})
|
|
```
|
|
|
|
#### `contents.addWorkSpace(path)`
|
|
|
|
* `path` String
|
|
|
|
Adds the specified path to DevTools workspace. Must be used after DevTools
|
|
creation:
|
|
|
|
```javascript
|
|
const { BrowserWindow } = require('electron')
|
|
let win = new BrowserWindow()
|
|
win.webContents.on('devtools-opened', () => {
|
|
win.webContents.addWorkSpace(__dirname)
|
|
})
|
|
```
|
|
|
|
#### `contents.removeWorkSpace(path)`
|
|
|
|
* `path` String
|
|
|
|
Removes the specified path from DevTools workspace.
|
|
|
|
#### `contents.setDevToolsWebContents(devToolsWebContents)`
|
|
|
|
* `devToolsWebContents` WebContents
|
|
|
|
Uses the `devToolsWebContents` as the target `WebContents` to show devtools.
|
|
|
|
The `devToolsWebContents` must not have done any navigation, and it should not
|
|
be used for other purposes after the call.
|
|
|
|
By default Electron manages the devtools by creating an internal `WebContents`
|
|
with native view, which developers have very limited control of. With the
|
|
`setDevToolsWebContents` method, developers can use any `WebContents` to show
|
|
the devtools in it, including `BrowserWindow`, `BrowserView` and `<webview>`
|
|
tag.
|
|
|
|
Note that closing the devtools does not destroy the `devToolsWebContents`, it
|
|
is caller's responsibility to destroy `devToolsWebContents`.
|
|
|
|
An example of showing devtools in a `<webview>` tag:
|
|
|
|
```html
|
|
<html>
|
|
<head>
|
|
<style type="text/css">
|
|
* { margin: 0; }
|
|
#browser { height: 70%; }
|
|
#devtools { height: 30%; }
|
|
</style>
|
|
</head>
|
|
<body>
|
|
<webview id="browser" src="https://github.com"></webview>
|
|
<webview id="devtools" src="about:blank"></webview>
|
|
<script>
|
|
const { webContents } = require('electron').remote
|
|
const emittedOnce = (element, eventName) => new Promise(resolve => {
|
|
element.addEventListener(eventName, event => resolve(event), { once: true })
|
|
})
|
|
const browserView = document.getElementById('browser')
|
|
const devtoolsView = document.getElementById('devtools')
|
|
const browserReady = emittedOnce(browserView, 'dom-ready')
|
|
const devtoolsReady = emittedOnce(devtoolsView, 'dom-ready')
|
|
Promise.all([browserReady, devtoolsReady]).then(() => {
|
|
const browser = webContents.fromId(browserView.getWebContentsId())
|
|
const devtools = webContents.fromId(devtoolsView.getWebContentsId())
|
|
browser.setDevToolsWebContents(devtools)
|
|
browser.openDevTools()
|
|
})
|
|
</script>
|
|
</body>
|
|
</html>
|
|
```
|
|
|
|
An example of showing devtools in a `BrowserWindow`:
|
|
|
|
```js
|
|
const { app, BrowserWindow } = require('electron')
|
|
|
|
let win = null
|
|
let devtools = null
|
|
|
|
app.whenReady().then(() => {
|
|
win = new BrowserWindow()
|
|
devtools = new BrowserWindow()
|
|
win.loadURL('https://github.com')
|
|
win.webContents.setDevToolsWebContents(devtools.webContents)
|
|
win.webContents.openDevTools({ mode: 'detach' })
|
|
})
|
|
```
|
|
|
|
#### `contents.openDevTools([options])`
|
|
|
|
* `options` Object (optional)
|
|
* `mode` String - Opens the devtools with specified dock state, can be
|
|
`right`, `bottom`, `undocked`, `detach`. Defaults to last used dock state.
|
|
In `undocked` mode it's possible to dock back. In `detach` mode it's not.
|
|
* `activate` Boolean (optional) - Whether to bring the opened devtools window
|
|
to the foreground. The default is `true`.
|
|
|
|
Opens the devtools.
|
|
|
|
When `contents` is a `<webview>` tag, the `mode` would be `detach` by default,
|
|
explicitly passing an empty `mode` can force using last used dock state.
|
|
|
|
#### `contents.closeDevTools()`
|
|
|
|
Closes the devtools.
|
|
|
|
#### `contents.isDevToolsOpened()`
|
|
|
|
Returns `Boolean` - Whether the devtools is opened.
|
|
|
|
#### `contents.isDevToolsFocused()`
|
|
|
|
Returns `Boolean` - Whether the devtools view is focused .
|
|
|
|
#### `contents.toggleDevTools()`
|
|
|
|
Toggles the developer tools.
|
|
|
|
#### `contents.inspectElement(x, y)`
|
|
|
|
* `x` Integer
|
|
* `y` Integer
|
|
|
|
Starts inspecting element at position (`x`, `y`).
|
|
|
|
#### `contents.inspectSharedWorker()`
|
|
|
|
Opens the developer tools for the shared worker context.
|
|
|
|
#### `contents.inspectSharedWorkerById(workerId)`
|
|
|
|
* `workerId` String
|
|
|
|
Inspects the shared worker based on its ID.
|
|
|
|
#### `contents.getAllSharedWorkers()`
|
|
|
|
Returns [`SharedWorkerInfo[]`](structures/shared-worker-info.md) - Information about all Shared Workers.
|
|
|
|
#### `contents.inspectServiceWorker()`
|
|
|
|
Opens the developer tools for the service worker context.
|
|
|
|
#### `contents.send(channel, ...args)`
|
|
|
|
* `channel` String
|
|
* `...args` any[]
|
|
|
|
Send an asynchronous message to the renderer process via `channel`, along with
|
|
arguments. Arguments will be serialized with the [Structured Clone
|
|
Algorithm][SCA], just like [`postMessage`][], so prototype chains will not be
|
|
included. Sending Functions, Promises, Symbols, WeakMaps, or WeakSets will
|
|
throw an exception.
|
|
|
|
> **NOTE**: Sending non-standard JavaScript types such as DOM objects or
|
|
> special Electron objects is deprecated, and will begin throwing an exception
|
|
> starting with Electron 9.
|
|
|
|
The renderer process can handle the message by listening to `channel` with the
|
|
[`ipcRenderer`](ipc-renderer.md) module.
|
|
|
|
An example of sending messages from the main process to the renderer process:
|
|
|
|
```javascript
|
|
// In the main process.
|
|
const { app, BrowserWindow } = require('electron')
|
|
let win = null
|
|
|
|
app.whenReady().then(() => {
|
|
win = new BrowserWindow({ width: 800, height: 600 })
|
|
win.loadURL(`file://${__dirname}/index.html`)
|
|
win.webContents.on('did-finish-load', () => {
|
|
win.webContents.send('ping', 'whoooooooh!')
|
|
})
|
|
})
|
|
```
|
|
|
|
```html
|
|
<!-- index.html -->
|
|
<html>
|
|
<body>
|
|
<script>
|
|
require('electron').ipcRenderer.on('ping', (event, message) => {
|
|
console.log(message) // Prints 'whoooooooh!'
|
|
})
|
|
</script>
|
|
</body>
|
|
</html>
|
|
```
|
|
|
|
#### `contents.sendToFrame(frameId, channel, ...args)`
|
|
|
|
* `frameId` Integer
|
|
* `channel` String
|
|
* `...args` any[]
|
|
|
|
Send an asynchronous message to a specific frame in a renderer process via
|
|
`channel`, along with arguments. Arguments will be serialized with the
|
|
[Structured Clone Algorithm][SCA], just like [`postMessage`][], so prototype
|
|
chains will not be included. Sending Functions, Promises, Symbols, WeakMaps, or
|
|
WeakSets will throw an exception.
|
|
|
|
> **NOTE**: Sending non-standard JavaScript types such as DOM objects or
|
|
> special Electron objects is deprecated, and will begin throwing an exception
|
|
> starting with Electron 9.
|
|
|
|
The renderer process can handle the message by listening to `channel` with the
|
|
[`ipcRenderer`](ipc-renderer.md) module.
|
|
|
|
If you want to get the `frameId` of a given renderer context you should use
|
|
the `webFrame.routingId` value. E.g.
|
|
|
|
```js
|
|
// In a renderer process
|
|
console.log('My frameId is:', require('electron').webFrame.routingId)
|
|
```
|
|
|
|
You can also read `frameId` from all incoming IPC messages in the main process.
|
|
|
|
```js
|
|
// In the main process
|
|
ipcMain.on('ping', (event) => {
|
|
console.info('Message came from frameId:', event.frameId)
|
|
})
|
|
```
|
|
|
|
#### `contents.postMessage(channel, message, [transfer])`
|
|
|
|
* `channel` String
|
|
* `message` any
|
|
* `transfer` MessagePortMain[] (optional)
|
|
|
|
Send a message to the renderer process, optionally transferring ownership of
|
|
zero or more [`MessagePortMain`][] objects.
|
|
|
|
The transferred `MessagePortMain` objects will be available in the renderer
|
|
process by accessing the `ports` property of the emitted event. When they
|
|
arrive in the renderer, they will be native DOM `MessagePort` objects.
|
|
|
|
For example:
|
|
```js
|
|
// Main process
|
|
const { port1, port2 } = new MessageChannelMain()
|
|
webContents.postMessage('port', { message: 'hello' }, [port1])
|
|
|
|
// Renderer process
|
|
ipcRenderer.on('port', (e, msg) => {
|
|
const [port] = e.ports
|
|
// ...
|
|
})
|
|
```
|
|
|
|
#### `contents.enableDeviceEmulation(parameters)`
|
|
|
|
* `parameters` Object
|
|
* `screenPosition` String - Specify the screen type to emulate
|
|
(default: `desktop`):
|
|
* `desktop` - Desktop screen type.
|
|
* `mobile` - Mobile screen type.
|
|
* `screenSize` [Size](structures/size.md) - Set the emulated screen size (screenPosition == mobile).
|
|
* `viewPosition` [Point](structures/point.md) - Position the view on the screen
|
|
(screenPosition == mobile) (default: `{ x: 0, y: 0 }`).
|
|
* `deviceScaleFactor` Integer - Set the device scale factor (if zero defaults to
|
|
original device scale factor) (default: `0`).
|
|
* `viewSize` [Size](structures/size.md) - Set the emulated view size (empty means no override)
|
|
* `scale` Float - Scale of emulated view inside available space (not in fit to
|
|
view mode) (default: `1`).
|
|
|
|
Enable device emulation with the given parameters.
|
|
|
|
#### `contents.disableDeviceEmulation()`
|
|
|
|
Disable device emulation enabled by `webContents.enableDeviceEmulation`.
|
|
|
|
#### `contents.sendInputEvent(inputEvent)`
|
|
|
|
* `inputEvent` [MouseInputEvent](structures/mouse-input-event.md) | [MouseWheelInputEvent](structures/mouse-wheel-input-event.md) | [KeyboardInputEvent](structures/keyboard-input-event.md)
|
|
|
|
Sends an input `event` to the page.
|
|
**Note:** The [`BrowserWindow`](browser-window.md) containing the contents needs to be focused for
|
|
`sendInputEvent()` to work.
|
|
|
|
#### `contents.beginFrameSubscription([onlyDirty ,]callback)`
|
|
|
|
* `onlyDirty` Boolean (optional) - Defaults to `false`.
|
|
* `callback` Function
|
|
* `image` [NativeImage](native-image.md)
|
|
* `dirtyRect` [Rectangle](structures/rectangle.md)
|
|
|
|
Begin subscribing for presentation events and captured frames, the `callback`
|
|
will be called with `callback(image, dirtyRect)` when there is a presentation
|
|
event.
|
|
|
|
The `image` is an instance of [NativeImage](native-image.md) that stores the
|
|
captured frame.
|
|
|
|
The `dirtyRect` is an object with `x, y, width, height` properties that
|
|
describes which part of the page was repainted. If `onlyDirty` is set to
|
|
`true`, `image` will only contain the repainted area. `onlyDirty` defaults to
|
|
`false`.
|
|
|
|
#### `contents.endFrameSubscription()`
|
|
|
|
End subscribing for frame presentation events.
|
|
|
|
#### `contents.startDrag(item)`
|
|
|
|
* `item` Object
|
|
* `file` String[] | String - The path(s) to the file(s) being dragged.
|
|
* `icon` [NativeImage](native-image.md) | String - The image must be
|
|
non-empty on macOS.
|
|
|
|
Sets the `item` as dragging item for current drag-drop operation, `file` is the
|
|
absolute path of the file to be dragged, and `icon` is the image showing under
|
|
the cursor when dragging.
|
|
|
|
#### `contents.savePage(fullPath, saveType)`
|
|
|
|
* `fullPath` String - The full file path.
|
|
* `saveType` String - Specify the save type.
|
|
* `HTMLOnly` - Save only the HTML of the page.
|
|
* `HTMLComplete` - Save complete-html page.
|
|
* `MHTML` - Save complete-html page as MHTML.
|
|
|
|
Returns `Promise<void>` - resolves if the page is saved.
|
|
|
|
```javascript
|
|
const { BrowserWindow } = require('electron')
|
|
let win = new BrowserWindow()
|
|
|
|
win.loadURL('https://github.com')
|
|
|
|
win.webContents.on('did-finish-load', async () => {
|
|
win.webContents.savePage('/tmp/test.html', 'HTMLComplete').then(() => {
|
|
console.log('Page was saved successfully.')
|
|
}).catch(err => {
|
|
console.log(err)
|
|
})
|
|
})
|
|
```
|
|
|
|
#### `contents.showDefinitionForSelection()` _macOS_
|
|
|
|
Shows pop-up dictionary that searches the selected word on the page.
|
|
|
|
#### `contents.isOffscreen()`
|
|
|
|
Returns `Boolean` - Indicates whether *offscreen rendering* is enabled.
|
|
|
|
#### `contents.startPainting()`
|
|
|
|
If *offscreen rendering* is enabled and not painting, start painting.
|
|
|
|
#### `contents.stopPainting()`
|
|
|
|
If *offscreen rendering* is enabled and painting, stop painting.
|
|
|
|
#### `contents.isPainting()`
|
|
|
|
Returns `Boolean` - If *offscreen rendering* is enabled returns whether it is currently painting.
|
|
|
|
#### `contents.setFrameRate(fps)`
|
|
|
|
* `fps` Integer
|
|
|
|
If *offscreen rendering* is enabled sets the frame rate to the specified number.
|
|
Only values between 1 and 60 are accepted.
|
|
|
|
#### `contents.getFrameRate()`
|
|
|
|
Returns `Integer` - If *offscreen rendering* is enabled returns the current frame rate.
|
|
|
|
#### `contents.invalidate()`
|
|
|
|
Schedules a full repaint of the window this web contents is in.
|
|
|
|
If *offscreen rendering* is enabled invalidates the frame and generates a new
|
|
one through the `'paint'` event.
|
|
|
|
#### `contents.getWebRTCIPHandlingPolicy()`
|
|
|
|
Returns `String` - Returns the WebRTC IP Handling Policy.
|
|
|
|
#### `contents.setWebRTCIPHandlingPolicy(policy)`
|
|
|
|
* `policy` String - Specify the WebRTC IP Handling Policy.
|
|
* `default` - Exposes user's public and local IPs. This is the default
|
|
behavior. When this policy is used, WebRTC has the right to enumerate all
|
|
interfaces and bind them to discover public interfaces.
|
|
* `default_public_interface_only` - Exposes user's public IP, but does not
|
|
expose user's local IP. When this policy is used, WebRTC should only use the
|
|
default route used by http. This doesn't expose any local addresses.
|
|
* `default_public_and_private_interfaces` - Exposes user's public and local
|
|
IPs. When this policy is used, WebRTC should only use the default route used
|
|
by http. This also exposes the associated default private address. Default
|
|
route is the route chosen by the OS on a multi-homed endpoint.
|
|
* `disable_non_proxied_udp` - Does not expose public or local IPs. When this
|
|
policy is used, WebRTC should only use TCP to contact peers or servers unless
|
|
the proxy server supports UDP.
|
|
|
|
Setting the WebRTC IP handling policy allows you to control which IPs are
|
|
exposed via WebRTC. See [BrowserLeaks](https://browserleaks.com/webrtc) for
|
|
more details.
|
|
|
|
#### `contents.getOSProcessId()`
|
|
|
|
Returns `Integer` - The operating system `pid` of the associated renderer
|
|
process.
|
|
|
|
#### `contents.getProcessId()`
|
|
|
|
Returns `Integer` - The Chromium internal `pid` of the associated renderer. Can
|
|
be compared to the `frameProcessId` passed by frame specific navigation events
|
|
(e.g. `did-frame-navigate`)
|
|
|
|
#### `contents.takeHeapSnapshot(filePath)`
|
|
|
|
* `filePath` String - Path to the output file.
|
|
|
|
Returns `Promise<void>` - Indicates whether the snapshot has been created successfully.
|
|
|
|
Takes a V8 heap snapshot and saves it to `filePath`.
|
|
|
|
#### `contents.setBackgroundThrottling(allowed)`
|
|
|
|
* `allowed` Boolean
|
|
|
|
Controls whether or not this WebContents will throttle animations and timers
|
|
when the page becomes backgrounded. This also affects the Page Visibility API.
|
|
|
|
#### `contents.getType()`
|
|
|
|
Returns `String` - the type of the webContent. Can be `backgroundPage`, `window`, `browserView`, `remote`, `webview` or `offscreen`.
|
|
|
|
### Instance Properties
|
|
|
|
#### `contents.audioMuted`
|
|
|
|
A `Boolean` property that determines whether this page is muted.
|
|
|
|
#### `contents.userAgent`
|
|
|
|
A `String` property that determines the user agent for this web page.
|
|
|
|
#### `contents.zoomLevel`
|
|
|
|
A `Number` property that determines the zoom level for this web contents.
|
|
|
|
The original size is 0 and each increment above or below represents zooming 20% larger or smaller to default limits of 300% and 50% of original size, respectively. The formula for this is `scale := 1.2 ^ level`.
|
|
|
|
#### `contents.zoomFactor`
|
|
|
|
A `Number` property that determines the zoom factor for this web contents.
|
|
|
|
The zoom factor is the zoom percent divided by 100, so 300% = 3.0.
|
|
|
|
#### `contents.frameRate`
|
|
|
|
An `Integer` property that sets the frame rate of the web contents to the specified number.
|
|
Only values between 1 and 60 are accepted.
|
|
|
|
Only applicable if *offscreen rendering* is enabled.
|
|
|
|
#### `contents.id` _Readonly_
|
|
|
|
A `Integer` representing the unique ID of this WebContents. Each ID is unique among all `WebContents` instances of the entire Electron application.
|
|
|
|
#### `contents.session` _Readonly_
|
|
|
|
A [`Session`](session.md) used by this webContents.
|
|
|
|
#### `contents.hostWebContents` _Readonly_
|
|
|
|
A [`WebContents`](web-contents.md) instance that might own this `WebContents`.
|
|
|
|
#### `contents.devToolsWebContents` _Readonly_
|
|
|
|
A `WebContents` of DevTools for this `WebContents`.
|
|
|
|
**Note:** Users should never store this object because it may become `null`
|
|
when the DevTools has been closed.
|
|
|
|
#### `contents.debugger` _Readonly_
|
|
|
|
A [`Debugger`](debugger.md) instance for this webContents.
|
|
|
|
[keyboardevent]: https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent
|
|
[event-emitter]: https://nodejs.org/api/events.html#events_class_eventemitter
|
|
[SCA]: https://developer.mozilla.org/en-US/docs/Web/API/Web_Workers_API/Structured_clone_algorithm
|
|
[`postMessage`]: https://developer.mozilla.org/en-US/docs/Web/API/Window/postMessage
|