wp-includes/js/customize-preview.js

   1 (function( exports, $ ){
   2         var api = wp.customize,
   3                 debounce;
   4
   5         debounce = function( fn, delay, context ) {
   6                 var timeout;
   7                 return function() {
   8                         var args = arguments;
   9
  10                         context = context || this;
  11
  12                         clearTimeout( timeout );
  13                         timeout = setTimeout( function() {
  14                                 timeout = null;
  15                                 fn.apply( context, args );
  16                         }, delay );
  17                 };
  18         };
  19
  20         api.Preview = api.Messenger.extend({
  21                 /**
  22                  * Requires params:
  23                  *  - url    - the URL of preview frame
  24                  */
  25                 initialize: function( params, options ) {
  26                         var self = this;
  27
  28                         api.Messenger.prototype.initialize.call( this, params, options );
  29
  30                         this.body = $( document.body );
  31                         this.body.on( 'click.preview', 'a', function( event ) {
  32                                 event.preventDefault();
  33                                 self.send( 'scroll', 0 );
  34                                 self.send( 'url', $(this).prop('href') );
  35                         });
  36
  37                         // You cannot submit forms.
  38                         // @todo: Allow form submissions by mixing $_POST data with the customize setting $_POST data.
  39                         this.body.on( 'submit.preview', 'form', function( event ) {
  40                                 event.preventDefault();
  41                         });
  42
  43                         this.window = $( window );
  44                         this.window.on( 'scroll.preview', debounce( function() {
  45                                 self.send( 'scroll', self.window.scrollTop() );
  46                         }, 200 ));
  47
  48                         this.bind( 'scroll', function( distance ) {
  49                                 self.window.scrollTop( distance );
  50                         });
  51                 }
  52         });
  53
  54         $( function() {
  55                 api.settings = window._wpCustomizeSettings;
  56                 if ( ! api.settings )
  57                         return;
  58
  59                 var preview, bg;
  60
  61                 preview = new api.Preview({
  62                         url: window.location.href,
  63                         channel: api.settings.channel
  64                 });
  65
  66                 preview.bind( 'settings', function( values ) {
  67                         $.each( values, function( id, value ) {
  68                                 if ( api.has( id ) )
  69                                         api( id ).set( value );
  70                                 else
  71                                         api.create( id, value );
  72                         });
  73                 });
  74
  75                 preview.trigger( 'settings', api.settings.values );
  76
  77                 preview.bind( 'setting', function( args ) {
  78                         var value;
  79
  80                         args = args.slice();
  81
  82                         if ( value = api( args.shift() ) )
  83                                 value.set.apply( value, args );
  84                 });
  85
  86                 preview.bind( 'sync', function( events ) {
  87                         $.each( events, function( event, args ) {
  88                                 preview.trigger( event, args );
  89                         });
  90                         preview.send( 'synced' );
  91                 });
  92
  93                 preview.bind( 'active', function() {
  94                         if ( api.settings.nonce )
  95                                 preview.send( 'nonce', api.settings.nonce );
  96                 });
  97
  98                 preview.send( 'ready' );
  99
 100                 /* Custom Backgrounds */
 101                 bg = $.map(['color', 'image', 'position_x', 'repeat', 'attachment'], function( prop ) {
 102                         return 'background_' + prop;
 103                 });
 104
 105                 api.when.apply( api, bg ).done( function( color, image, position_x, repeat, attachment ) {
 106                         var body = $(document.body),
 107                                 head = $('head'),
 108                                 style = $('#custom-background-css'),
 109                                 update;
 110
 111                         // If custom backgrounds are active and we can't find the
 112                         // default output, bail.
 113                         if ( body.hasClass('custom-background') && ! style.length )
 114                                 return;
 115
 116                         update = function() {
 117                                 var css = '';
 118
 119                                 // The body will support custom backgrounds if either
 120                                 // the color or image are set.
 121                                 //
 122                                 // See get_body_class() in /wp-includes/post-template.php
 123                                 body.toggleClass( 'custom-background', !! ( color() || image() ) );
 124
 125                                 if ( color() )
 126                                         css += 'background-color: ' + color() + ';';
 127
 128                                 if ( image() ) {
 129                                         css += 'background-image: url("' + image() + '");';
 130                                         css += 'background-position: top ' + position_x() + ';';
 131                                         css += 'background-repeat: ' + repeat() + ';';
 132                                         css += 'background-attachment: ' + attachment() + ';';
 133                                 }
 134
 135                                 // Refresh the stylesheet by removing and recreating it.
 136                                 style.remove();
 137                                 style = $('<style type="text/css" id="custom-background-css">body.custom-background { ' + css + ' }</style>').appendTo( head );
 138                         };
 139
 140                         $.each( arguments, function() {
 141                                 this.bind( update );
 142                         });
 143                 });
 144         });
 145
 146 })( wp, jQuery );