Changeset 20257

Timestamp:

03/22/2012 06:52:44 AM (15 years ago)

Author:

koopersmith

Message:

Theme Customizer: In JavaScript, add the ability to execute a callback once a set of values have been initialized. see #19910.

File:

• trunk/wp-includes/js/customize-base.dev.js (modified) (4 diffs)

trunk/wp-includes/js/customize-base.dev.js

@@ -378 +378 @@
                 initialize: function( options ) {
                         api.Value.prototype.initialize.call( this, {}, options || {} );
+                        this._deferreds = {};
                 },
 
                 instance: function( id ) {
-                        return this.value( id );
+                        if ( arguments.length === 1 )
+                                return this.value( id );
+
+                        return this.when.apply( this, arguments );
                 },
 
@@ -398 +402 @@
                         this._value[ id ] = value;
                         this._value[ id ]._parent = this._value;
+
+                        if ( this._deferreds[ id ] )
+                                this._deferreds[ id ].resolve();
+
                         return this._value[ id ];
                 },
@@ -410 +418 @@
                 remove: function( id ) {
                         delete this._value[ id ];
+                        delete this._deferreds[ id ];
                 },
 
@@ -423 +432 @@
                         value = this.value( id );
                         return value[ fn ].apply( value, args );
+                },
+
+                /**
+                 * Runs a callback once all requested values exist.
+                 *
+                 * when( ids*, callback );
+                 *
+                 * For example:
+                 *     when( id1, id2, id3, function( value1, value2, value3 ) {} );
+                 */
+                when: function() {
+                        var self = this,
+                                ids = slice.call( arguments ),
+                                callback = ids.pop();
+
+                        $.when.apply( $, $.map( ids, function( id ) {
+                                if ( self.has( id ) )
+                                        return;
+
+                                return self._deferreds[ id ] || ( self._deferreds[ id ] = $.Deferred() );
+                        })).done( function() {
+                                var values = $.map( ids, function( id ) {
+                                                return self( id );
+                                        });
+
+                                // If a value is missing, we've used at least one expired deferred.
+                                // Call Values.when again to update our master deferred.
+                                if ( values.length !== ids.length ) {
+                                        ids.push( callback );
+                                        self.when.apply( self, ids );
+                                        return;
+                                }
+
+                                callback.apply( self, values );
+                        });
                 }
         });