jquery-mobile/js/jquery.mobile.event.js

/*
* jQuery Mobile Framework : events
* Copyright (c) jQuery Project
* Dual licensed under the MIT or GPL Version 2 licenses.
* http://jquery.org/license
*/
(function($, undefined ) {

// add new event shortcuts
$.each( "touchstart touchmove touchend orientationchange tap taphold swipe swipeleft swiperight scrollstart scrollstop".split( " " ), function( i, name ) {
	$.fn[ name ] = function( fn ) {
		return fn ? this.bind( name, fn ) : this.trigger( name );
	};
	$.attrFn[ name ] = true;
});

var supportTouch = $.support.touch,
	scrollEvent = "touchmove scroll",
	touchStartEvent = supportTouch ? "touchstart" : "mousedown",
	touchStopEvent = supportTouch ? "touchend" : "mouseup",
	touchMoveEvent = supportTouch ? "touchmove" : "mousemove";

// also handles scrollstop
$.event.special.scrollstart = {
	enabled: true,
	
	setup: function() {
		var thisObject = this,
			$this = $( thisObject ),
			scrolling,
			timer;
		
		function trigger( event, state ) {
			scrolling = state;
			var originalType = event.type;
			event.type = scrolling ? "scrollstart" : "scrollstop";
			$.event.handle.call( thisObject, event );
			event.type = originalType;
		}
		
		// iPhone triggers scroll after a small delay; use touchmove instead
		$this.bind( scrollEvent, function( event ) {
			if ( !$.event.special.scrollstart.enabled ) {
				return;
			}
			
			if ( !scrolling ) {
				trigger( event, true );
			}
			
			clearTimeout( timer );
			timer = setTimeout(function() {
				trigger( event, false );
			}, 50 );
		});
	}
};

// also handles taphold
$.event.special.tap = {
	setup: function() {
		var thisObject = this,
			$this = $( thisObject );
		
		$this
			.bind("vmousedown", function( event ) {
				if ( event.which && event.which !== 1 ) {
					return false;
				}
				
				var moved = false,
					touching = true,
					origTarget = event.target,
					origEvent = event.originalEvent,
					origPos = [ event.pageX, event.pageY ],
					originalType,
					timer;
					
				
				function moveHandler( event ) {
					if( event.type == "scroll" ){
						moved = true;
						return;
					}
					var newPageXY = event;
					if ((Math.abs(origPos[0] - newPageXY.pageX) > 10) ||
					    (Math.abs(origPos[1] - newPageXY.pageY) > 10)) {
					    moved = true;
					}
				}
				
				timer = setTimeout(function() {
					if ( touching && !moved ) {
						originalType = event.type;
						event.type = "taphold";
						$.event.handle.call( thisObject, event );
						event.type = originalType;
					}
				}, 750 );
				
				//scroll now cancels tap
				$(window).one("scroll", moveHandler);
				
				$this
					.bind( "vmousemove", moveHandler )
					.one( "vmouseup", function( event ) {
						$this.unbind( "vmousemove", moveHandler );
						$(window).unbind("scroll", moveHandler);
						clearTimeout( timer );
						touching = false;
						
						/* ONLY trigger a 'tap' event if the start target is
						 * the same as the stop target.
						 */
						if ( !moved && ( origTarget == event.target ) ) {
							originalType = event.type;
							event.type = "tap";
							$.event.handle.call( thisObject, event );
							event.type = originalType;
						}
					});
			});
	}
};

// also handles swipeleft, swiperight
$.event.special.swipe = {
	setup: function() {
		var thisObject = this,
			$this = $( thisObject );
		
		$this
			.bind( touchStartEvent, function( event ) {
				var data = event.originalEvent.touches ?
						event.originalEvent.touches[ 0 ] :
						event,
					start = {
						time: (new Date).getTime(),
						coords: [ data.pageX, data.pageY ],
						origin: $( event.target )
					},
					stop;
				
				function moveHandler( event ) {
					if ( !start ) {
						return;
					}
					
					var data = event.originalEvent.touches ?
							event.originalEvent.touches[ 0 ] :
							event;
					stop = {
							time: (new Date).getTime(),
							coords: [ data.pageX, data.pageY ]
					};
					
					// prevent scrolling
					if ( Math.abs( start.coords[0] - stop.coords[0] ) > 10 ) {
						event.preventDefault();
					}
				}
				
				$this
					.bind( touchMoveEvent, moveHandler )
					.one( touchStopEvent, function( event ) {
						$this.unbind( touchMoveEvent, moveHandler );
						if ( start && stop ) {
							if ( stop.time - start.time < 1000 && 
									Math.abs( start.coords[0] - stop.coords[0]) > 30 &&
									Math.abs( start.coords[1] - stop.coords[1]) < 75 ) {
								start.origin
								.trigger( "swipe" )
								.trigger( start.coords[0] > stop.coords[0] ? "swipeleft" : "swiperight" );
							}
						}
						start = stop = undefined;
					});
			});
	}
};

(function($){
	// "Cowboy" Ben Alman
	
	var win = $(window),
		special_event,
		get_orientation,
		last_orientation;
	
	$.event.special.orientationchange = special_event = {
		setup: function(){
			// If the event is supported natively, return false so that jQuery
			// will bind to the event using DOM methods.
			if ( $.support.orientation ) { return false; }
			
			// Get the current orientation to avoid initial double-triggering.
			last_orientation = get_orientation();
			
			// Because the orientationchange event doesn't exist, simulate the
			// event by testing window dimensions on resize.
			win.bind( "resize", handler );
		},
		teardown: function(){
			// If the event is not supported natively, return false so that
			// jQuery will unbind the event using DOM methods.
			if ( $.support.orientation ) { return false; }
			
			// Because the orientationchange event doesn't exist, unbind the
			// resize event handler.
			win.unbind( "resize", handler );
		},
		add: function( handleObj ) {
			// Save a reference to the bound event handler.
			var old_handler = handleObj.handler;
			
			handleObj.handler = function( event ) {
				// Modify event object, adding the .orientation property.
				event.orientation = get_orientation();
				
				// Call the originally-bound event handler and return its result.
				return old_handler.apply( this, arguments );
			};
		}
	};
	
	// If the event is not supported natively, this handler will be bound to
	// the window resize event to simulate the orientationchange event.
	function handler() {
		// Get the current orientation.
		var orientation = get_orientation();
		
		if ( orientation !== last_orientation ) {
			// The orientation has changed, so trigger the orientationchange event.
			last_orientation = orientation;
			win.trigger( "orientationchange" );
		}
	};
	
	// Get the current page orientation. This method is exposed publicly, should it
	// be needed, as jQuery.event.special.orientationchange.orientation()
	special_event.orientation = get_orientation = function() {
		var elem = document.documentElement;
		return elem && elem.clientWidth / elem.clientHeight < 1.1 ? "portrait" : "landscape";
	};
	
})(jQuery);

$.each({
	scrollstop: "scrollstart",
	taphold: "tap",
	swipeleft: "swipe",
	swiperight: "swipe"
}, function( event, sourceEvent ) {
	$.event.special[ event ] = {
		setup: function() {
			$( this ).bind( sourceEvent, $.noop );
		}
	};
});

})( jQuery );