jquery.mobile.forms.select.custom.js

/*
* jQuery Mobile Framework : custom "selectmenu" plugin
* Copyright (c) jQuery Project
* Dual licensed under the MIT or GPL Version 2 licenses.
* http://jquery.org/license
*/

(function( $, undefined ) {
	var extendSelect = function( widget ){

		var select = widget.select,
			selectID  = widget.selectID,
			label = widget.label,
			thisPage = widget.select.closest( ".ui-page" ),
			screen = $( "<div>", {"class": "ui-selectmenu-screen ui-screen-hidden"} ).appendTo( thisPage ),
			selectOptions = widget._selectOptions(),
			isMultiple = widget.isMultiple = widget.select[ 0 ].multiple,
			buttonId = selectID + "-button",
			menuId = selectID + "-menu",
			menuPage = $( "<div data-" + $.mobile.ns + "role='dialog' data-" +$.mobile.ns + "theme='"+ widget.options.overlayTheme +"'>" +
				"<div data-" + $.mobile.ns + "role='header'>" +
				"<div class='ui-title'>" + label.getEncodedText() + "</div>"+
				"</div>"+
				"<div data-" + $.mobile.ns + "role='content'></div>"+
				"</div>" ).appendTo( $.mobile.pageContainer ).page(),

			listbox =  $("<div>", { "class": "ui-selectmenu ui-selectmenu-hidden ui-overlay-shadow ui-corner-all ui-body-" + widget.options.overlayTheme + " " + $.mobile.defaultDialogTransition } ).insertAfter(screen),

			list = $( "<ul>", {
				"class": "ui-selectmenu-list",
				"id": menuId,
				"role": "listbox",
				"aria-labelledby": buttonId
			}).attr( "data-" + $.mobile.ns + "theme", widget.options.theme ).appendTo( listbox ),

			header = $( "<div>", {
				"class": "ui-header ui-bar-" + widget.options.theme
			}).prependTo( listbox ),

			headerTitle = $( "<h1>", {
				"class": "ui-title"
			}).appendTo( header ),

			headerClose = $( "<a>", {
				"text": widget.options.closeText,
				"href": "#",
				"class": "ui-btn-left"
			}).attr( "data-" + $.mobile.ns + "iconpos", "notext" ).attr( "data-" + $.mobile.ns + "icon", "delete" ).appendTo( header ).buttonMarkup(),

			menuPageContent = menuPage.find( ".ui-content" ),

			menuPageClose = menuPage.find( ".ui-header a" );


		$.extend( widget, {
			select: widget.select,
			selectID: selectID,
			buttonId: buttonId,
			menuId: menuId,
			thisPage: thisPage,
			menuPage: menuPage,
			label: label,
			screen: screen,
			selectOptions: selectOptions,
			isMultiple: isMultiple,
			theme: widget.options.theme,
			listbox: listbox,
			list: list,
			header: header,
			headerTitle: headerTitle,
			headerClose: headerClose,
			menuPageContent: menuPageContent,
			menuPageClose: menuPageClose,
			placeholder: "",

			build: function() {
				var self = this;

				// Create list from select, update state
				self.refresh();

				self.select.attr( "tabindex", "-1" ).focus(function() {
					$( this ).blur();
					self.button.focus();
				});

				// Button events
				self.button.bind( "vclick keydown" , function( event ) {
					if ( event.type == "vclick" ||
							 event.keyCode && ( event.keyCode === $.mobile.keyCode.ENTER ||
																	event.keyCode === $.mobile.keyCode.SPACE ) ) {

						self.open();
						event.preventDefault();
					}
				});

				// Events for list items
				self.list.attr( "role", "listbox" )
					.delegate( ".ui-li>a", "focusin", function() {
						$( this ).attr( "tabindex", "0" );
					})
					.delegate( ".ui-li>a", "focusout", function() {
						$( this ).attr( "tabindex", "-1" );
					})
					.delegate( "li:not(.ui-disabled, .ui-li-divider)", "click", function( event ) {

						// index of option tag to be selected
						var oldIndex = self.select[ 0 ].selectedIndex,
							newIndex = self.list.find( "li:not(.ui-li-divider)" ).index( this ),
							option = self._selectOptions().eq( newIndex )[ 0 ];

						// toggle selected status on the tag for multi selects
						option.selected = self.isMultiple ? !option.selected : true;

						// toggle checkbox class for multiple selects
						if ( self.isMultiple ) {
							$( this ).find( ".ui-icon" )
								.toggleClass( "ui-icon-checkbox-on", option.selected )
								.toggleClass( "ui-icon-checkbox-off", !option.selected );
						}

						// trigger change if value changed
						if ( self.isMultiple || oldIndex !== newIndex ) {
							self.select.trigger( "change" );
						}

						//hide custom select for single selects only
						if ( !self.isMultiple ) {
							self.close();
						}

						event.preventDefault();
					})
					.keydown(function( event ) {  //keyboard events for menu items
						var target = $( event.target ),
							li = target.closest( "li" ),
							prev, next;

						// switch logic based on which key was pressed
						switch ( event.keyCode ) {
							// up or left arrow keys
						 case 38:
							prev = li.prev();

							// if there's a previous option, focus it
							if ( prev.length ) {
								target
									.blur()
									.attr( "tabindex", "-1" );

								prev.find( "a" ).first().focus();
							}

							return false;
							break;

							// down or right arrow keys
						 case 40:
							next = li.next();

							// if there's a next option, focus it
							if ( next.length ) {
								target
									.blur()
									.attr( "tabindex", "-1" );

								next.find( "a" ).first().focus();
							}

							return false;
							break;

							// If enter or space is pressed, trigger click
						 case 13:
						 case 32:
							target.trigger( "click" );

							return false;
							break;
						}
					});

				// button refocus ensures proper height calculation
				// by removing the inline style and ensuring page inclusion
				self.menuPage.bind( "pagehide", function() {
					self.list.appendTo( self.listbox );
					self._focusButton();

					// TODO centralize page removal binding / handling in the page plugin.
					// Suggestion from @jblas to do refcounting
					//
					// TODO extremely confusing dependency on the open method where the pagehide.remove
					// bindings are stripped to prevent the parent page from disappearing. The way
					// we're keeping pages in the DOM right now sucks
					//
					// rebind the page remove that was unbound in the open function
					// to allow for the parent page removal from actions other than the use
					// of a dialog sized custom select
					//
					// doing this here provides for the back button on the custom select dialog
					$.mobile._bindPageRemove.call( self.thisPage );
				});

				// Events on "screen" overlay
				self.screen.bind( "vclick", function( event ) {
					self.close();
				});

				// Close button on small overlays
				self.headerClose.click( function() {
					if ( self.menuType == "overlay" ) {
						self.close();
						return false;
					}
				});

				// track this dependency so that when the parent page
				// is removed on pagehide it will also remove the menupage
				self.thisPage.addDependents( this.menuPage );
			},

			_isRebuildRequired: function() {
				var list = this.list.find( "li" ),
					options = this._selectOptions();

				// TODO exceedingly naive method to determine difference
				// ignores value changes etc in favor of a forcedRebuild
				// from the user in the refresh method
				return options.text() !== list.text();
			},

			refresh: function( forceRebuild , foo ){
				var self = this,
				select = this.element,
				isMultiple = this.isMultiple,
				options = this._selectOptions(),
				selected = this.selected(),
				// return an array of all selected index's
				indicies = this.selectedIndices();

				if (  forceRebuild || this._isRebuildRequired() ) {
					self._buildList();
				}

				self.setButtonText();
				self.setButtonCount();

				self.list.find( "li:not(.ui-li-divider)" )
					.removeClass( $.mobile.activeBtnClass )
					.attr( "aria-selected", false )
					.each(function( i ) {

						if ( $.inArray( i, indicies ) > -1 ) {
							var item = $( this );

							// Aria selected attr
							item.attr( "aria-selected", true );

							// Multiple selects: add the "on" checkbox state to the icon
							if ( self.isMultiple ) {
								item.find( ".ui-icon" ).removeClass( "ui-icon-checkbox-off" ).addClass( "ui-icon-checkbox-on" );
							} else {
								item.addClass( $.mobile.activeBtnClass );
							}
						}
					});
			},

			close: function() {
				if ( this.options.disabled || !this.isOpen ) {
					return;
				}

				var self = this;

				if ( self.menuType == "page" ) {
					// doesn't solve the possible issue with calling change page
					// where the objects don't define data urls which prevents dialog key
					// stripping - changePage has incoming refactor
					window.history.back();
				} else {
					self.screen.addClass( "ui-screen-hidden" );
					self.listbox.addClass( "ui-selectmenu-hidden" ).removeAttr( "style" ).removeClass( "in" );
					self.list.appendTo( self.listbox );
					self._focusButton();
				}

				// allow the dialog to be closed again
				self.isOpen = false;
			},

			open: function() {
				if ( this.options.disabled ) {
					return;
				}

				var self = this,
					menuHeight = self.list.parent().outerHeight(),
					menuWidth = self.list.parent().outerWidth(),
					activePage = $( ".ui-page-active" ),
					tOverflow = $.support.touchOverflow && $.mobile.touchOverflowEnabled,
					tScrollElem = activePage.is( ".ui-native-fixed" ) ? activePage.find( ".ui-content" ) : activePage;
					scrollTop = tOverflow ? tScrollElem.scrollTop() : $( window ).scrollTop(),
					btnOffset = self.button.offset().top,
					screenHeight = window.innerHeight,
					screenWidth = window.innerWidth;

				//add active class to button
				self.button.addClass( $.mobile.activeBtnClass );

				//remove after delay
				setTimeout( function() {
					self.button.removeClass( $.mobile.activeBtnClass );
				}, 300);

				function focusMenuItem() {
					self.list.find( $.mobile.activeBtnClass ).focus();
				}

				if ( menuHeight > screenHeight - 80 || !$.support.scrollTop ) {
					// prevent the parent page from being removed from the DOM,
					// otherwise the results of selecting a list item in the dialog
					// fall into a black hole
					self.thisPage.unbind( "pagehide.remove" );

					//for webos (set lastscroll using button offset)
					if ( scrollTop == 0 && btnOffset > screenHeight ) {
						self.thisPage.one( "pagehide", function() {
							$( this ).jqmData( "lastScroll", btnOffset );
						});
					}

					self.menuPage.one( "pageshow", function() {
						// silentScroll() is called whenever a page is shown to restore
						// any previous scroll position the page may have had. We need to
						// wait for the "silentscroll" event before setting focus to avoid
						// the browser"s "feature" which offsets rendering to make sure
						// whatever has focus is in view.
						$( window ).one( "silentscroll", function() {
							focusMenuItem();
						});

						self.isOpen = true;
					});

					self.menuType = "page";
					self.menuPageContent.append( self.list );
					self.menuPage.find("div .ui-title").text(self.label.text());
					$.mobile.changePage( self.menuPage, {
						transition: $.mobile.defaultDialogTransition
					});
				} else {
					self.menuType = "overlay";

					self.screen.height( $(document).height() )
						.removeClass( "ui-screen-hidden" );

					// Try and center the overlay over the button
					var roomtop = btnOffset - scrollTop,
						roombot = scrollTop + screenHeight - btnOffset,
						halfheight = menuHeight / 2,
						maxwidth = parseFloat( self.list.parent().css( "max-width" ) ),
						newtop, newleft;

					if ( roomtop > menuHeight / 2 && roombot > menuHeight / 2 ) {
						newtop = btnOffset + ( self.button.outerHeight() / 2 ) - halfheight;
					} else {
						// 30px tolerance off the edges
						newtop = roomtop > roombot ? scrollTop + screenHeight - menuHeight - 30 : scrollTop + 30;
					}

					// If the menuwidth is smaller than the screen center is
					if ( menuWidth < maxwidth ) {
						newleft = ( screenWidth - menuWidth ) / 2;
					} else {

						//otherwise insure a >= 30px offset from the left
						newleft = self.button.offset().left + self.button.outerWidth() / 2 - menuWidth / 2;

						// 30px tolerance off the edges
						if ( newleft < 30 ) {
							newleft = 30;
						} else if ( (newleft + menuWidth) > screenWidth ) {
							newleft = screenWidth - menuWidth - 30;
						}
					}

					self.listbox.append( self.list )
						.removeClass( "ui-selectmenu-hidden" )
						.css({
							top: newtop,
							left: newleft
						})
						.addClass( "in" );

					focusMenuItem();

					// duplicate with value set in page show for dialog sized selects
					self.isOpen = true;
				}
			},

			_buildList: function() {
				var self = this,
					o = this.options,
					placeholder = this.placeholder,
					optgroups = [],
					lis = [],
					dataIcon = self.isMultiple ? "checkbox-off" : "false";

				self.list.empty().filter( ".ui-listview" ).listview( "destroy" );

				// Populate menu with options from select element
				self.select.find( "option" ).each( function( i ) {
					var $this = $( this ),
						$parent = $this.parent(),
						text = $this.getEncodedText(),
						anchor = "<a href='#'>"+ text +"</a>",
						classes = [],
						extraAttrs = [];

					// Are we inside an optgroup?
					if ( $parent.is( "optgroup" ) ) {
						var optLabel = $parent.attr( "label" );

						// has this optgroup already been built yet?
						if ( $.inArray( optLabel, optgroups ) === -1 ) {
							lis.push( "<li data-" + $.mobile.ns + "role='list-divider'>"+ optLabel +"</li>" );
							optgroups.push( optLabel );
						}
					}

					// Find placeholder text
					// TODO: Are you sure you want to use getAttribute? ^RW
					if ( !this.getAttribute( "value" ) || text.length == 0 || $this.jqmData( "placeholder" ) ) {
						if ( o.hidePlaceholderMenuItems ) {
							classes.push( "ui-selectmenu-placeholder" );
						}
						placeholder = self.placeholder = text;
					}

					// support disabled option tags
					if ( this.disabled ) {
						classes.push( "ui-disabled" );
						extraAttrs.push( "aria-disabled='true'" );
					}

					lis.push( "<li data-" + $.mobile.ns + "option-index='" + i + "' data-" + $.mobile.ns + "icon='"+ dataIcon +"' class='"+ classes.join(" ") + "' " + extraAttrs.join(" ") +">"+ anchor +"</li>" );
				});

				self.list.html( lis.join(" ") );

				self.list.find( "li" )
					.attr({ "role": "option", "tabindex": "-1" })
					.first().attr( "tabindex", "0" );

				// Hide header close link for single selects
				if ( !this.isMultiple ) {
					this.headerClose.hide();
				}

				// Hide header if it's not a multiselect and there's no placeholder
				if ( !this.isMultiple && !placeholder.length ) {
					this.header.hide();
				} else {
					this.headerTitle.text( this.placeholder );
				}

				// Now populated, create listview
				self.list.listview();
			},

			_button: function(){
				return $( "<a>", {
					"href": "#",
					"role": "button",
					// TODO value is undefined at creation
					"id": this.buttonId,
					"aria-haspopup": "true",

					// TODO value is undefined at creation
					"aria-owns": this.menuId
				});
			}
		});
	};

	$( "select" ).live( "selectmenubeforecreate", function(){
		var selectmenuWidget = $( this ).data( "selectmenu" );

		if( !selectmenuWidget.options.nativeMenu ){
			extendSelect( selectmenuWidget );
		}
	});
})( jQuery );