/**
* @license Copyright (c) 2003-2017, CKSource - Frederico Knabben. All rights reserved.
* For licensing, see LICENSE.md or http://ckeditor.com/license
*/
/**
* @fileOverview Defines the {@link CKEDITOR.event} class, which serves as the
* base for classes and objects that require event handling features.
*/
if ( !CKEDITOR.event ) {
/**
* Creates an event class instance. This constructor is rarely used, being
* the {@link #implementOn} function used in class prototypes directly
* instead.
*
* This is a base class for classes and objects that require event
* handling features.
*
* Do not confuse this class with {@link CKEDITOR.dom.event} which is
* instead used for DOM events. The CKEDITOR.event class implements the
* internal event system used by the CKEditor to fire API related events.
*
* @class
* @constructor Creates an event class instance.
*/
CKEDITOR.event = function() {};
/**
* Implements the {@link CKEDITOR.event} features in an object.
*
* var myObject = { message: 'Example' };
* CKEDITOR.event.implementOn( myObject );
*
* myObject.on( 'testEvent', function() {
* alert( this.message );
* } );
* myObject.fire( 'testEvent' ); // 'Example'
*
* @static
* @param {Object} targetObject The object into which implement the features.
*/
CKEDITOR.event.implementOn = function( targetObject ) {
var eventProto = CKEDITOR.event.prototype;
for ( var prop in eventProto ) {
if ( targetObject[ prop ] == null )
targetObject[ prop ] = eventProto[ prop ];
}
};
CKEDITOR.event.prototype = ( function() {
// Returns the private events object for a given object.
var getPrivate = function( obj ) {
var _ = ( obj.getPrivate && obj.getPrivate() ) || obj._ || ( obj._ = {} );
return _.events || ( _.events = {} );
};
var eventEntry = function( eventName ) {
this.name = eventName;
this.listeners = [];
};
eventEntry.prototype = {
// Get the listener index for a specified function.
// Returns -1 if not found.
getListenerIndex: function( listenerFunction ) {
for ( var i = 0, listeners = this.listeners; i < listeners.length; i++ ) {
if ( listeners[ i ].fn == listenerFunction )
return i;
}
return -1;
}
};
// Retrieve the event entry on the event host (create it if needed).
function getEntry( name ) {
// Get the event entry (create it if needed).
var events = getPrivate( this );
return events[ name ] || ( events[ name ] = new eventEntry( name ) );
}
return {
/**
* Predefine some intrinsic properties on a specific event name.
*
* @param {String} name The event name
* @param meta
* @param [meta.errorProof=false] Whether the event firing should catch error thrown from a per listener call.
*/
define: function( name, meta ) {
var entry = getEntry.call( this, name );
CKEDITOR.tools.extend( entry, meta, true );
},
/**
* Registers a listener to a specific event in the current object.
*
* someObject.on( 'someEvent', function() {
* alert( this == someObject ); // true
* } );
*
* someObject.on( 'someEvent', function() {
* alert( this == anotherObject ); // true
* }, anotherObject );
*
* someObject.on( 'someEvent', function( event ) {
* alert( event.listenerData ); // 'Example'
* }, null, 'Example' );
*
* someObject.on( 'someEvent', function() { ... } ); // 2nd called
* someObject.on( 'someEvent', function() { ... }, null, null, 100 ); // 3rd called
* someObject.on( 'someEvent', function() { ... }, null, null, 1 ); // 1st called
*
* @param {String} eventName The event name to which listen.
* @param {Function} listenerFunction The function listening to the
* event. A single {@link CKEDITOR.eventInfo} object instanced
* is passed to this function containing all the event data.
* @param {Object} [scopeObj] The object used to scope the listener
* call (the `this` object). If omitted, the current object is used.
* @param {Object} [listenerData] Data to be sent as the
* {@link CKEDITOR.eventInfo#listenerData} when calling the
* listener.
* @param {Number} [priority=10] The listener priority. Lower priority
* listeners are called first. Listeners with the same priority
* value are called in registration order.
* @returns {Object} An object containing the `removeListener`
* function, which can be used to remove the listener at any time.
*/
on: function( eventName, listenerFunction, scopeObj, listenerData, priority ) {
// Create the function to be fired for this listener.
function listenerFirer( editor, publisherData, stopFn, cancelFn ) {
var ev = {
name: eventName,
sender: this,
editor: editor,
data: publisherData,
listenerData: listenerData,
stop: stopFn,
cancel: cancelFn,
removeListener: removeListener
};
var ret = listenerFunction.call( scopeObj, ev );
return ret === false ? false : ev.data;
}
function removeListener() {
me.removeListener( eventName, listenerFunction );
}
var event = getEntry.call( this, eventName );
if ( event.getListenerIndex( listenerFunction ) < 0 ) {
// Get the listeners.
var listeners = event.listeners;
// Fill the scope.
if ( !scopeObj )
scopeObj = this;
// Default the priority, if needed.
if ( isNaN( priority ) )
priority = 10;
var me = this;
listenerFirer.fn = listenerFunction;
listenerFirer.priority = priority;
// Search for the right position for this new listener, based on its
// priority.
for ( var i = listeners.length - 1; i >= 0; i-- ) {
// Find the item which should be before the new one.
if ( listeners[ i ].priority <= priority ) {
// Insert the listener in the array.
listeners.splice( i + 1, 0, listenerFirer );
return { removeListener: removeListener };
}
}
// If no position has been found (or zero length), put it in
// the front of list.
listeners.unshift( listenerFirer );
}
return { removeListener: removeListener };
},
/**
* Similiar with {@link #on} but the listener will be called only once upon the next event firing.
*
* @see CKEDITOR.event#on
*/
once: function() {
var args = Array.prototype.slice.call( arguments ),
fn = args[ 1 ];
args[ 1 ] = function( evt ) {
evt.removeListener();
return fn.apply( this, arguments );
};
return this.on.apply( this, args );
},
/**
* @static
* @property {Boolean} useCapture
* @todo
*/
/**
* Register event handler under the capturing stage on supported target.
*/
capture: function() {
CKEDITOR.event.useCapture = 1;
var retval = this.on.apply( this, arguments );
CKEDITOR.event.useCapture = 0;
return retval;
},
/**
* Fires an specific event in the object. All registered listeners are
* called at this point.
*
* someObject.on( 'someEvent', function() { ... } );
* someObject.on( 'someEvent', function() { ... } );
* someObject.fire( 'someEvent' ); // Both listeners are called.
*
* someObject.on( 'someEvent', function( event ) {
* alert( event.data ); // 'Example'
* } );
* someObject.fire( 'someEvent', 'Example' );
*
* @method
* @param {String} eventName The event name to fire.
* @param {Object} [data] Data to be sent as the
* {@link CKEDITOR.eventInfo#data} when calling the listeners.
* @param {CKEDITOR.editor} [editor] The editor instance to send as the
* {@link CKEDITOR.eventInfo#editor} when calling the listener.
* @returns {Boolean/Object} A boolean indicating that the event is to be
* canceled, or data returned by one of the listeners.
*/
fire: ( function() {
// Create the function that marks the event as stopped.
var stopped = 0;
var stopEvent = function() {
stopped = 1;
};
// Create the function that marks the event as canceled.
var canceled = 0;
var cancelEvent = function() {
canceled = 1;
};
return function( eventName, data, editor ) {
// Get the event entry.
var event = getPrivate( this )[ eventName ];
// Save the previous stopped and cancelled states. We may
// be nesting fire() calls.
var previousStopped = stopped,
previousCancelled = canceled;
// Reset the stopped and canceled flags.
stopped = canceled = 0;
if ( event ) {
var listeners = event.listeners;
if ( listeners.length ) {
// As some listeners may remove themselves from the
// event, the original array length is dinamic. So,
// let's make a copy of all listeners, so we are
// sure we'll call all of them.
listeners = listeners.slice( 0 );
var retData;
// Loop through all listeners.
for ( var i = 0; i < listeners.length; i++ ) {
// Call the listener, passing the event data.
if ( event.errorProof ) {
try {
retData = listeners[ i ].call( this, editor, data, stopEvent, cancelEvent );
} catch ( er ) {}
} else {
retData = listeners[ i ].call( this, editor, data, stopEvent, cancelEvent );
}
if ( retData === false )
canceled = 1;
else if ( typeof retData != 'undefined' )
data = retData;
// No further calls is stopped or canceled.
if ( stopped || canceled )
break;
}
}
}
var ret = canceled ? false : ( typeof data == 'undefined' ? true : data );
// Restore the previous stopped and canceled states.
stopped = previousStopped;
canceled = previousCancelled;
return ret;
};
} )(),
/**
* Fires an specific event in the object, releasing all listeners
* registered to that event. The same listeners are not called again on
* successive calls of it or of {@link #fire}.
*
* someObject.on( 'someEvent', function() { ... } );
* someObject.fire( 'someEvent' ); // Above listener called.
* someObject.fireOnce( 'someEvent' ); // Above listener called.
* someObject.fire( 'someEvent' ); // No listeners called.
*
* @param {String} eventName The event name to fire.
* @param {Object} [data] Data to be sent as the
* {@link CKEDITOR.eventInfo#data} when calling the listeners.
* @param {CKEDITOR.editor} [editor] The editor instance to send as the
* {@link CKEDITOR.eventInfo#editor} when calling the listener.
* @returns {Boolean/Object} A booloan indicating that the event is to be
* canceled, or data returned by one of the listeners.
*/
fireOnce: function( eventName, data, editor ) {
var ret = this.fire( eventName, data, editor );
delete getPrivate( this )[ eventName ];
return ret;
},
/**
* Unregisters a listener function from being called at the specified
* event. No errors are thrown if the listener has not been registered previously.
*
* var myListener = function() { ... };
* someObject.on( 'someEvent', myListener );
* someObject.fire( 'someEvent' ); // myListener called.
* someObject.removeListener( 'someEvent', myListener );
* someObject.fire( 'someEvent' ); // myListener not called.
*
* @param {String} eventName The event name.
* @param {Function} listenerFunction The listener function to unregister.
*/
removeListener: function( eventName, listenerFunction ) {
// Get the event entry.
var event = getPrivate( this )[ eventName ];
if ( event ) {
var index = event.getListenerIndex( listenerFunction );
if ( index >= 0 )
event.listeners.splice( index, 1 );
}
},
/**
* Remove all existing listeners on this object, for cleanup purpose.
*/
removeAllListeners: function() {
var events = getPrivate( this );
for ( var i in events )
delete events[ i ];
},
/**
* Checks if there is any listener registered to a given event.
*
* var myListener = function() { ... };
* someObject.on( 'someEvent', myListener );
* alert( someObject.hasListeners( 'someEvent' ) ); // true
* alert( someObject.hasListeners( 'noEvent' ) ); // false
*
* @param {String} eventName The event name.
* @returns {Boolean}
*/
hasListeners: function( eventName ) {
var event = getPrivate( this )[ eventName ];
return ( event && event.listeners.length > 0 );
}
};
} )();
}
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