resources/jquery/jquery.placeholder.js

   1 /**
   2  * HTML5 placeholder emulation for jQuery plugin
   3  *
   4  * This will automatically use the HTML5 placeholder attribute if supported, or emulate this behavior if not.
   5  *
   6  * @author Trevor Parscal <tparscal@wikimedia.org>
   7  * @author Krinkle <krinklemail@gmail.com>
   8  * @version 0.2.0
   9  * @license GPL v2
  10  */
  11 ( function( $ ) {
  12
  13 $.fn.placeholder = function() {
  14
  15         return this.each( function() {
  16
  17                 // If the HTML5 placeholder attribute is supported, use it
  18                 if ( this.placeholder && 'placeholder' in document.createElement( this.tagName ) ) {
  19                         return;
  20                 }
  21
  22                 var placeholder = this.getAttribute( 'placeholder' );
  23                 var $input = $(this);
  24
  25                 // Show initially, if empty
  26                 if ( this.value === '' || this.value === placeholder ) {
  27                         $input.addClass( 'placeholder' ).val( placeholder );
  28                 }
  29
  30                 $input
  31                         // Show on blur if empty
  32                         .blur( function() {
  33                                 if ( this.value === '' ) {
  34                                         this.value = placeholder;
  35                                         $input.addClass( 'placeholder' );
  36                                 }
  37                         } )
  38
  39                         // Hide on focus
  40                         // Also listen for other events in case $input was
  41                         // already focused when the events were bound
  42                         .bind( 'focus drop keydown paste', function( e ) {
  43                                 if ( $input.hasClass( 'placeholder' ) ) {
  44                                         // Support for drag&drop in Firefox
  45                                         if ( e.type == 'drop' && e.originalEvent.dataTransfer ) {
  46                                                 this.value = e.originalEvent.dataTransfer.getData( 'text/plain' );
  47                                         } else {
  48                                                 this.value = '';
  49                                         }
  50                                         $input.removeClass( 'placeholder' );
  51                                 }
  52                         } );
  53
  54                 // Blank on submit -- prevents submitting with unintended value
  55                 if ( this.form ) {
  56                         $( this.form ).submit( function() {
  57                                 // $input.trigger( 'focus' ); would be problematic
  58                                 // because it actually focuses $input, leading
  59                                 // to nasty behavior in mobile browsers
  60                                 if ( $input.hasClass( 'placeholder' ) ) {
  61                                         $input
  62                                                 .val( '' )
  63                                                 .removeClass( 'placeholder' );
  64                                 }
  65                         });
  66                 }
  67
  68         });
  69 };
  70 } )( jQuery );