electron/atom/renderer/lib/web-view/web-view.coffee

299 lines
10 KiB
CoffeeScript

v8Util = process.atomBinding 'v8_util'
guestViewInternal = require './guest-view-internal'
webViewConstants = require './web-view-constants'
webFrame = require 'web-frame'
remote = require 'remote'
# ID generator.
nextId = 0
getNextId = -> ++nextId
# Represents the internal state of the WebView node.
class WebViewImpl
constructor: (@webviewNode) ->
v8Util.setHiddenValue @webviewNode, 'internal', this
@attached = false
@pendingGuestCreation = false
@elementAttached = false
@beforeFirstNavigation = true
@contentWindow = null
# on* Event handlers.
@on = {}
@browserPluginNode = @createBrowserPluginNode()
shadowRoot = @webviewNode.createShadowRoot()
@setupWebViewAttributes()
@setupFocusPropagation()
@setupWebviewNodeProperties()
@viewInstanceId = getNextId()
guestViewInternal.registerEvents this, @viewInstanceId
shadowRoot.appendChild @browserPluginNode
createBrowserPluginNode: ->
# We create BrowserPlugin as a custom element in order to observe changes
# to attributes synchronously.
browserPluginNode = new WebViewImpl.BrowserPlugin()
v8Util.setHiddenValue browserPluginNode, 'internal', this
browserPluginNode
# Resets some state upon reattaching <webview> element to the DOM.
reset: ->
# If guestInstanceId is defined then the <webview> has navigated and has
# already picked up a partition ID. Thus, we need to reset the initialization
# state. However, it may be the case that beforeFirstNavigation is false BUT
# guestInstanceId has yet to be initialized. This means that we have not
# heard back from createGuest yet. We will not reset the flag in this case so
# that we don't end up allocating a second guest.
if @guestInstanceId
guestViewInternal.destroyGuest @guestInstanceId
@guestInstanceId = undefined
@beforeFirstNavigation = true
@attributes[webViewConstants.ATTRIBUTE_PARTITION].validPartitionId = true
@contentWindow = null
@internalInstanceId = 0
# Sets the <webview>.request property.
setRequestPropertyOnWebViewNode: (request) ->
Object.defineProperty @webviewNode, 'request', value: request, enumerable: true
setupFocusPropagation: ->
unless @webviewNode.hasAttribute 'tabIndex'
# <webview> needs a tabIndex in order to be focusable.
# TODO(fsamuel): It would be nice to avoid exposing a tabIndex attribute
# to allow <webview> to be focusable.
# See http://crbug.com/231664.
@webviewNode.setAttribute 'tabIndex', -1
@webviewNode.addEventListener 'focus', (e) =>
# Focus the BrowserPlugin when the <webview> takes focus.
@browserPluginNode.focus()
@webviewNode.addEventListener 'blur', (e) =>
# Blur the BrowserPlugin when the <webview> loses focus.
@browserPluginNode.blur()
setupWebviewNodeProperties: ->
# We cannot use {writable: true} property descriptor because we want a
# dynamic getter value.
Object.defineProperty @webviewNode, 'contentWindow',
get: =>
return @contentWindow if @contentWindow?
window.console.error webViewConstants.ERROR_MSG_CONTENTWINDOW_NOT_AVAILABLE
# No setter.
enumerable: true
# This observer monitors mutations to attributes of the <webview> and
# updates the BrowserPlugin properties accordingly. In turn, updating
# a BrowserPlugin property will update the corresponding BrowserPlugin
# attribute, if necessary. See BrowserPlugin::UpdateDOMAttribute for more
# details.
handleWebviewAttributeMutation: (attributeName, oldValue, newValue) ->
if not @attributes[attributeName] or @attributes[attributeName].ignoreMutation
return
# Let the changed attribute handle its own mutation;
@attributes[attributeName].handleMutation oldValue, newValue
handleBrowserPluginAttributeMutation: (attributeName, oldValue, newValue) ->
if attributeName is webViewConstants.ATTRIBUTE_INTERNALINSTANCEID and !oldValue and !!newValue
@browserPluginNode.removeAttribute webViewConstants.ATTRIBUTE_INTERNALINSTANCEID
@internalInstanceId = parseInt newValue
return unless @guestInstanceId
guestViewInternal.attachGuest @internalInstanceId, @guestInstanceId, @buildAttachParams(), (w) => @contentWindow = w
onSizeChanged: (webViewEvent) ->
newWidth = webViewEvent.newWidth
newHeight = webViewEvent.newHeight
node = @webviewNode
width = node.offsetWidth
height = node.offsetHeight
# Check the current bounds to make sure we do not resize <webview>
# outside of current constraints.
maxWidth = @attributes[webViewConstants.ATTRIBUTE_MAXWIDTH].getValue() | width
maxHeight = @attributes[webViewConstants.ATTRIBUTE_MAXHEIGHT].getValue() | width
minWidth = @attributes[webViewConstants.ATTRIBUTE_MINWIDTH].getValue() | width
minHeight = @attributes[webViewConstants.ATTRIBUTE_MINHEIGHT].getValue() | width
if not @attributes[webViewConstants.ATTRIBUTE_AUTOSIZE].getValue() or
(newWidth >= minWidth and
newWidth <= maxWidth and
newHeight >= minHeight and
newHeight <= maxHeight)
node.style.width = newWidth + 'px'
node.style.height = newHeight + 'px'
# Only fire the DOM event if the size of the <webview> has actually
# changed.
@dispatchEvent webViewEvent
createGuest: ->
return if @pendingGuestCreation
params =
storagePartitionId: @attributes[webViewConstants.ATTRIBUTE_PARTITION].getValue()
guestViewInternal.createGuest 'webview', params, (guestInstanceId) =>
@pendingGuestCreation = false
unless @elementAttached
guestViewInternal.destroyGuest guestInstanceId
return
@attachWindow guestInstanceId
@pendingGuestCreation = true
dispatchEvent: (webViewEvent) ->
@webviewNode.dispatchEvent webViewEvent
# Adds an 'on<event>' property on the webview, which can be used to set/unset
# an event handler.
setupEventProperty: (eventName) ->
propertyName = 'on' + eventName.toLowerCase()
Object.defineProperty @webviewNode, propertyName,
get: => @on[propertyName]
set: (value) =>
if @on[propertyName]
@webviewNode.removeEventListener eventName, @on[propertyName]
@on[propertyName] = value
if value
@webviewNode.addEventListener eventName, value
enumerable: true
# Updates state upon loadcommit.
onLoadCommit: (@baseUrlForDataUrl, @currentEntryIndex, @entryCount, @processId, url, isTopLevel) ->
oldValue = @webviewNode.getAttribute webViewConstants.ATTRIBUTE_SRC
newValue = url
if isTopLevel and (oldValue != newValue)
# Touching the src attribute triggers a navigation. To avoid
# triggering a page reload on every guest-initiated navigation,
# we do not handle this mutation
@attributes[webViewConstants.ATTRIBUTE_SRC].setValueIgnoreMutation newValue
onAttach: (storagePartitionId) ->
@attributes[webViewConstants.ATTRIBUTE_PARTITION].setValue storagePartitionId
buildAttachParams: ->
params =
instanceId: @viewInstanceId
userAgentOverride: @userAgentOverride
for attributeName, attribute of @attributes
params[attributeName] = attribute.getValue()
params
attachWindow: (guestInstanceId) ->
@guestInstanceId = guestInstanceId
params = @buildAttachParams()
return true unless @internalInstanceId
guestViewInternal.attachGuest @internalInstanceId, @guestInstanceId, params, (w) => @contentWindow = w
# Registers browser plugin <object> custom element.
registerBrowserPluginElement = ->
proto = Object.create HTMLObjectElement.prototype
proto.createdCallback = ->
@setAttribute 'type', 'application/browser-plugin'
@setAttribute 'id', 'browser-plugin-' + getNextId()
# The <object> node fills in the <webview> container.
@style.width = '100%'
@style.height = '100%'
proto.attributeChangedCallback = (name, oldValue, newValue) ->
internal = v8Util.getHiddenValue this, 'internal'
return unless internal
internal.handleBrowserPluginAttributeMutation name, oldValue, newValue
proto.attachedCallback = ->
# Load the plugin immediately.
unused = this.nonExistentAttribute
WebViewImpl.BrowserPlugin = webFrame.registerEmbedderCustomElement 'browserplugin',
extends: 'object', prototype: proto
delete proto.createdCallback
delete proto.attachedCallback
delete proto.detachedCallback
delete proto.attributeChangedCallback
# Registers <webview> custom element.
registerWebViewElement = ->
proto = Object.create HTMLObjectElement.prototype
proto.createdCallback = ->
new WebViewImpl(this)
proto.attributeChangedCallback = (name, oldValue, newValue) ->
internal = v8Util.getHiddenValue this, 'internal'
return unless internal
internal.handleWebviewAttributeMutation name, oldValue, newValue
proto.detachedCallback = ->
internal = v8Util.getHiddenValue this, 'internal'
return unless internal
internal.elementAttached = false
internal.reset()
proto.attachedCallback = ->
internal = v8Util.getHiddenValue this, 'internal'
return unless internal
unless internal.elementAttached
internal.elementAttached = true
internal.attributes[webViewConstants.ATTRIBUTE_SRC].parse()
# Public-facing API methods.
methods = [
"getUrl"
"getTitle"
"isLoading"
"isWaitingForResponse"
"stop"
"reload"
"reloadIgnoringCache"
"canGoBack"
"canGoForward"
"canGoToOffset"
"goBack"
"goForward"
"goToIndex"
"goToOffset"
"isCrashed"
"setUserAgent"
"executeJavaScript"
"insertCSS"
"openDevTools"
"closeDevTools"
"isDevToolsOpened"
"send"
"getId"
]
# Forward proto.foo* method calls to WebViewImpl.foo*.
createHandler = (m) ->
(args...) ->
internal = v8Util.getHiddenValue this, 'internal'
remote.getGuestWebContents(internal.guestInstanceId)[m] args...
proto[m] = createHandler m for m in methods
window.WebView = webFrame.registerEmbedderCustomElement 'webview',
prototype: proto
# Delete the callbacks so developers cannot call them and produce unexpected
# behavior.
delete proto.createdCallback
delete proto.attachedCallback
delete proto.detachedCallback
delete proto.attributeChangedCallback
useCapture = true
listener = (event) ->
return if document.readyState == 'loading'
registerBrowserPluginElement()
registerWebViewElement()
window.removeEventListener event.type, listener, useCapture
window.addEventListener 'readystatechange', listener, true
module.exports = WebViewImpl