DragControllerDesktop.java

/* 
 * Copyright 2011 Vancouver Ywebb Consulting Ltd
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 * ---------
 * This class contains modified sources from gwtmobile-ui project. 
 * 
 * Copyright (c) 2010 Zhihua (Dennis) Jiang
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */
package next.i.mobile;

import next.i.util.Utils;

import com.google.gwt.dom.client.Element;
import com.google.gwt.dom.client.EventTarget;
import com.google.gwt.user.client.Event;

public class DragControllerDesktop extends DragController {

	DragControllerDesktop() {
	}

	@Override
	protected void registerEvents() {
		super.registerEvents();
		if (_dragStartListener == null) {
			_dragStartListener = Utils.addEventListener(_source.getElement(), "mousedown", true, this);
			_dragMoveListener = Utils.addEventListener(_source.getElement(), "mousemove", true, this);
			_dragEndListener = Utils.addEventListener(_source.getElement(), "mouseup", true, this);
		}
	}

	@Override
	protected void unregisterEvents() {
		super.unregisterEvents();
		if (_dragStartListener != null) {
			Utils.removeEventListener(_source.getElement(), "mousedown", true, _dragStartListener);
			Utils.removeEventListener(_source.getElement(), "mousemove", true, _dragMoveListener);
			Utils.removeEventListener(_source.getElement(), "mouseup", true, _dragEndListener);
			_dragStartListener = _dragMoveListener = _dragEndListener = null;
		}
	}

	public void onMouseDown(Event e) {
		//XLog.info("onMouseDown " + e.getType() + " from drag controller desktop.");
		EventTarget target = e.getEventTarget();
		boolean preventDefault = true;
		if (Element.is(target)) {
			Element ele = Element.as(target);
			// INPUT element will not get focus if default action is prevented.
			if (Utils.isHtmlFormControl(ele)) {
				ele.focus();
				preventDefault = false;
			}
		}
		if (preventDefault) {
			e.preventDefault(); // prevent default action of selecting text
			e.stopPropagation();
			onStart(e, new Point(e.getClientX(), e.getClientY()));
		}
	}

	public void onMouseMove(Event e) {
		e.preventDefault();
		e.stopPropagation();
		onMove(e, new Point(e.getClientX(), e.getClientY()));
	}

	public void onMouseUp(Event e) {
		e.preventDefault();
		e.stopPropagation();
		onEnd(e, new Point(e.getClientX(), e.getClientY()));
	}

	@Override
	public void onBrowserEvent(Event e) {
		String type = e.getType();
//		XLog.info("onBrowserEvent " + type + " from drag controller desktop.");
		if (type.equals("mousedown")) {
			onMouseDown(e);
		} else if (type.equals("mousemove")) {
			onMouseMove(e);
		} else if (type.equals("mouseup")) {
			onMouseUp(e);
		} else {
			super.onBrowserEvent(e);
		}
	}
}