8.8 KiB
webFrame
Customize the rendering of the current web page.
Process: Renderer
webFrame
export of the Electron module is an instance of the WebFrame
class representing the top frame of the current BrowserWindow
. Sub-frames can
be retrieved by certain properties and methods (e.g. webFrame.firstChild
).
An example of zooming current page to 200%.
const { webFrame } = require('electron')
webFrame.setZoomFactor(2)
Methods
The WebFrame
class has the following instance methods:
webFrame.setZoomFactor(factor)
factor
Number - Zoom factor.
Changes the zoom factor to the specified factor. Zoom factor is zoom percent divided by 100, so 300% = 3.0.
webFrame.getZoomFactor()
Returns Number
- The current zoom factor.
webFrame.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.
webFrame.getZoomLevel()
Returns Number
- The current zoom level.
webFrame.setVisualZoomLevelLimits(minimumLevel, maximumLevel)
minimumLevel
NumbermaximumLevel
Number
Sets the maximum and minimum pinch-to-zoom level.
webFrame.setLayoutZoomLevelLimits(minimumLevel, maximumLevel)
minimumLevel
NumbermaximumLevel
Number
Sets the maximum and minimum layout-based (i.e. non-visual) zoom level.
webFrame.setSpellCheckProvider(language, autoCorrectWord, provider)
language
StringautoCorrectWord
Booleanprovider
ObjectspellCheck
Function - ReturnsBoolean
.text
String
Sets a provider for spell checking in input fields and text areas.
The provider
must be an object that has a spellCheck
method that returns
whether the word passed is correctly spelled.
An example of using node-spellchecker as provider:
const { webFrame } = require('electron')
webFrame.setSpellCheckProvider('en-US', true, {
spellCheck (text) {
return !(require('spellchecker').isMisspelled(text))
}
})
webFrame.registerURLSchemeAsBypassingCSP(scheme)
scheme
String
Resources will be loaded from this scheme
regardless of the current page's
Content Security Policy.
webFrame.registerURLSchemeAsPrivileged(scheme[, options])
scheme
Stringoptions
Object (optional)secure
Boolean (optional) - Default true.bypassCSP
Boolean (optional) - Default true.allowServiceWorkers
Boolean (optional) - Default true.supportFetchAPI
Boolean (optional) - Default true.corsEnabled
Boolean (optional) - Default true.
Registers the scheme
as secure, bypasses content security policy for resources,
allows registering ServiceWorker and supports fetch API.
Specify an option with the value of false
to omit it from the registration.
An example of registering a privileged scheme, without bypassing Content Security Policy:
const { webFrame } = require('electron')
webFrame.registerURLSchemeAsPrivileged('foo', { bypassCSP: false })
webFrame.insertText(text)
text
String
Inserts text
to the focused element.
webFrame.executeJavaScript(code[, userGesture, callback])
code
StringuserGesture
Boolean (optional) - Default isfalse
.callback
Function (optional) - Called after script has been executed.result
Any
Returns Promise
- 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.
webFrame.executeJavaScriptInIsolatedWorld(worldId, scripts[, userGesture, callback])
worldId
Integer - The ID of the world to run the javascript in,0
is the default world,999
is the world used by ElectronscontextIsolation
feature. You can provide any integer here.scripts
WebSource[]userGesture
Boolean (optional) - Default isfalse
.callback
Function (optional) - Called after script has been executed.result
Any
Work like executeJavaScript
but evaluates scripts
in an isolated context.
webFrame.setIsolatedWorldContentSecurityPolicy(worldId, csp)
worldId
Integer - The ID of the world to run the javascript in,0
is the default world,999
is the world used by ElectronscontextIsolation
feature. You can provide any integer here.csp
String
Set the content security policy of the isolated world.
webFrame.setIsolatedWorldHumanReadableName(worldId, name)
worldId
Integer - The ID of the world to run the javascript in,0
is the default world,999
is the world used by ElectronscontextIsolation
feature. You can provide any integer here.name
String
Set the name of the isolated world. Useful in devtools.
webFrame.setIsolatedWorldSecurityOrigin(worldId, securityOrigin)
worldId
Integer - The ID of the world to run the javascript in,0
is the default world,999
is the world used by ElectronscontextIsolation
feature. You can provide any integer here.securityOrigin
String
Set the security origin of the isolated world.
webFrame.getResourceUsage()
Returns Object
:
images
MemoryUsageDetailsscripts
MemoryUsageDetailscssStyleSheets
MemoryUsageDetailsxslStyleSheets
MemoryUsageDetailsfonts
MemoryUsageDetailsother
MemoryUsageDetails
Returns an object describing usage information of Blink's internal memory caches.
const { webFrame } = require('electron')
console.log(webFrame.getResourceUsage())
This will generate:
{
images: {
count: 22,
size: 2549,
liveSize: 2542
},
cssStyleSheets: { /* same with "images" */ },
xslStyleSheets: { /* same with "images" */ },
fonts: { /* same with "images" */ },
other: { /* same with "images" */ }
}
webFrame.clearCache()
Attempts to free memory that is no longer being used (like images from a previous navigation).
Note that blindly calling this method probably makes Electron slower since it will have to refill these emptied caches, you should only call it if an event in your app has occurred that makes you think your page is actually using less memory (i.e. you have navigated from a super heavy page to a mostly empty one, and intend to stay there).
webFrame.getFrameForSelector(selector)
selector
String - CSS selector for a frame element.
Returns WebFrame
- The frame element in webFrame's
document selected by
selector
, null
would be returned if selector
does not select a frame or
if the frame is not in the current renderer process.
webFrame.findFrameByName(name)
name
String
Returns WebFrame
- A child of webFrame
with the supplied name
, null
would be returned if there's no such frame or if the frame is not in the current
renderer process.
webFrame.findFrameByRoutingId(routingId)
routingId
Integer - AnInteger
representing the unique frame id in the current renderer process. Routing IDs can be retrieved fromWebFrame
instances (webFrame.routingId
) and are also passed by frame specificWebContents
navigation events (e.g.did-frame-navigate
)
Returns WebFrame
- that has the supplied routingId
, null
if not found.
Properties
webFrame.top
A WebFrame
representing top frame in frame hierarchy to which webFrame
belongs, the property would be null
if top frame is not in the current
renderer process.
webFrame.opener
A WebFrame
representing the frame which opened webFrame
, the property would
be null
if there's no opener or opener is not in the current renderer process.
webFrame.parent
A WebFrame
representing parent frame of webFrame
, the property would be
null
if webFrame
is top or parent is not in the current renderer process.
webFrame.firstChild
A WebFrame
representing the first child frame of webFrame
, the property
would be null
if webFrame
has no children or if first child is not in the
current renderer process.
webFrame.nextSibling
A WebFrame
representing next sibling frame, the property would be null
if
webFrame
is the last frame in its parent or if the next sibling is not in the
current renderer process.
webFrame.routingId
An Integer
representing the unique frame id in the current renderer process.
Distinct WebFrame instances that refer to the same underlying frame will have
the same routingId
.