mediawiki-extensions-Visual.../modules/ve/ui/ve.ui.Frame.js
Trevor Parscal 17c9aadf8f Simplified iframe initialization
Rather than attach a function to the window and trigger it from a script
tag in the document body, it's much simpler to just use the references
we already have to execute the code immediately and directly.

This also fixes issues in Firefox where reaching in and adding functions
to the window wasn't allowed.

Change-Id: If7a84edf6ae4549b19ce36a3477311c46dbadea7
2013-04-16 12:59:11 -07:00

135 lines
3.5 KiB
JavaScript

/*!
* VisualEditor UserInterface Frame class.
*
* @copyright 2011-2013 VisualEditor Team and others; see AUTHORS.txt
* @license The MIT License (MIT); see LICENSE.txt
*/
/**
* UserInterface iframe abstraction.
*
* @class
* @extends ve.EventEmitter
*
* @constructor
* @param {Object} [config] Config options
* @cfg {string[]} [stylesheets] List of stylesheet file names, each relative to ve/ui/styles
*/
ve.ui.Frame = function VeUiFrame( config ) {
// Inheritance
ve.EventEmitter.call( this );
// Properties
this.initialized = false;
this.config = config;
this.$ = $( '<iframe>' );
// Events
this.$.load( ve.bind( this.onLoad, this ) );
// Initialize
this.$
.addClass( 've-ui-frame' )
.attr( { 'frameborder': 0, 'scrolling': 'no' } );
};
/* Inheritance */
ve.inheritClass( ve.ui.Frame, ve.EventEmitter );
/* Events */
/**
* @event initialize
*/
/* Methods */
/**
* Handle frame load events.
*
* Once the iframe's stylesheets are loaded, the `initialize` event will be emitted.
*
* Sounds simple right? Read on...
*
* When you create a dynamic iframe using open/write/close, the window.load event for the
* iframe is triggered when you call close, and there's no further load event to indicate that
* everything is actually loaded.
*
* By dynamically adding stylesheet links, we can detect when each link is loaded by testing if we
* have access to each of their `sheet.cssRules` properties. Every 10ms we poll to see if we have
* access to the style's `sheet.cssRules` property yet.
*
* However, because of security issues, we never have such access if the stylesheet came from a
* different site. Thus, we are left with linking to the stylesheets through a style element with
* multiple `@import` statements - which ends up being simpler anyway. Since we created that style,
* we always have access, and its contents are only available when everything is done loading.
*
* @emits initialize
*/
ve.ui.Frame.prototype.onLoad = function () {
var interval, rules,
win = this.$.prop( 'contentWindow' ),
doc = win.document,
style = doc.createElement( 'style' ),
initialize = ve.bind( function () {
this.initialized = true;
this.emit( 'initialize' );
}, this );
// Initialize contents
doc.open();
doc.write(
'<body style="padding:0;margin:0;">' +
'<div class="ve-ui-frame-content"></div>' +
'</body>'
);
doc.close();
// Import all stylesheets
style.textContent = '@import "' + this.config.stylesheets.join( '";\n@import "' ) + '";';
doc.body.appendChild( style );
// Poll for access to stylesheet content
interval = setInterval( ve.bind( function () {
try {
// MAGIC: only accessible when the stylesheet is loaded
rules = style.sheet.cssRules;
// If that didn't throw an exception, we're done loading
clearInterval( interval );
// Protect against IE running interval one extra time after clearing
if ( !this.initialized ) {
initialize();
}
} catch ( e ) { }
}, this ), 10 );
// Properties
this.$$ = ve.ui.get$$( doc, this );
this.$content = this.$$( '.ve-ui-frame-content' );
};
/**
* @param {Function} callback
*/
ve.ui.Frame.prototype.run = function ( callback ) {
if ( this.initialized ) {
callback();
} else {
this.once( 'initialize', callback );
}
};
/**
* Sets the size of the frame.
*
* @method
* @param {number} width Frame width in pixels
* @param {number} height Frame height in pixels
* @chainable
*/
ve.ui.Frame.prototype.setSize = function ( width, height ) {
this.$.css( { 'width': width, 'height': height } );
return this;
};