+
+ register: function(draggable) {
+ if(this.drags.length == 0) {
+ this.eventMouseUp = this.endDrag.bindAsEventListener(this);
+ this.eventMouseMove = this.updateDrag.bindAsEventListener(this);
+ this.eventKeypress = this.keyPress.bindAsEventListener(this);
+
+ Event.observe(document, "mouseup", this.eventMouseUp);
+ Event.observe(document, "mousemove", this.eventMouseMove);
+ Event.observe(document, "keypress", this.eventKeypress);
+ }
+ this.drags.push(draggable);
+ },
+
+ unregister: function(draggable) {
+ this.drags = this.drags.reject(function(d) { return d==draggable });
+ if(this.drags.length == 0) {
+ Event.stopObserving(document, "mouseup", this.eventMouseUp);
+ Event.stopObserving(document, "mousemove", this.eventMouseMove);
+ Event.stopObserving(document, "keypress", this.eventKeypress);
+ }
+ },
+
+ activate: function(draggable) {
+ if(draggable.options.delay) {
+ this._timeout = setTimeout(function() {
+ Draggables._timeout = null;
+ window.focus();
+ Draggables.activeDraggable = draggable;
+ }.bind(this), draggable.options.delay);
+ } else {
+ window.focus(); // allows keypress events if window isn't currently focused, fails for Safari
+ this.activeDraggable = draggable;
+ }
+ },
+
+ deactivate: function() {
+ this.activeDraggable = null;
+ },
+
+ updateDrag: function(event) {
+ if(!this.activeDraggable) return;
+ var pointer = [Event.pointerX(event), Event.pointerY(event)];
+ // Mozilla-based browsers fire successive mousemove events with
+ // the same coordinates, prevent needless redrawing (moz bug?)
+ if(this._lastPointer && (this._lastPointer.inspect() == pointer.inspect())) return;
+ this._lastPointer = pointer;
+
+ this.activeDraggable.updateDrag(event, pointer);
+ },
+
+ endDrag: function(event) {
+ if(this._timeout) {
+ clearTimeout(this._timeout);
+ this._timeout = null;
+ }
+ if(!this.activeDraggable) return;
+ this._lastPointer = null;
+ this.activeDraggable.endDrag(event);
+ this.activeDraggable = null;
+ },
+
+ keyPress: function(event) {
+ if(this.activeDraggable)
+ this.activeDraggable.keyPress(event);
+ },
+