Drag Tracker Sample (Smart GWT)
/* * SmartGWT (GWT for SmartClient) * Copyright 2008 and beyond, Isomorphic Software, Inc. * * SmartGWT is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License version 3 * as published by the Free Software Foundation. SmartGWT is also * available under typical commercial license terms - see * http://smartclient.com/license * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. */ package com.smartgwt.sample.showcase.client; import com.google.gwt.core.client.EntryPoint; import com.google.gwt.user.client.ui.RootPanel; import com.smartgwt.client.types.Alignment; import com.smartgwt.client.types.DragAppearance; import com.smartgwt.client.util.EventHandler; import com.smartgwt.client.util.SC; import com.smartgwt.client.widgets.Canvas; import com.smartgwt.client.widgets.Img; import com.smartgwt.client.widgets.Label; import com.smartgwt.client.widgets.events.DropEvent; import com.smartgwt.client.widgets.events.DropHandler; import com.smartgwt.client.widgets.events.DropOutEvent; import com.smartgwt.client.widgets.events.DropOutHandler; import com.smartgwt.client.widgets.events.DropOverEvent; import com.smartgwt.client.widgets.events.DropOverHandler; public class Showcase implements EntryPoint { public void onModuleLoad() { RootPanel.get().add(getViewPanel()); } public Canvas getViewPanel() { DragPiece blue = new DragPiece("pawn_blue.png") { protected boolean setDragTracker() { EventHandler.setDragTracker("Blue Piece"); return false; } }; blue.setID("bluePiece"); blue.setTitle("Blue Piece"); blue.setLeft(50); blue.setTop(50); DragPiece green = new DragPiece("pawn_green.png"){ protected boolean setDragTracker() { String html = Canvas.imgHTML("pieces/24/pawn_green.png", 24, 24); EventHandler.setDragTracker(html); return false; } }; green.setID("greenPiece"); green.setTitle("Green Piece"); green.setLeft(150); green.setTop(50); final Label label = new Label("Drop Here"); label.setLeft(250); label.setTop(50); label.setShowEdges(true); label.setAlign(Alignment.CENTER); label.setCanAcceptDrop(true); label.addDropOverHandler(new DropOverHandler() { public void onDropOver(DropOverEvent event) { label.setBackgroundColor("#ffff80"); } }); label.addDropOutHandler(new DropOutHandler() { public void onDropOut(DropOutEvent event) { label.setBackgroundColor("#ffffff"); } }); label.addDropHandler(new DropHandler() { public void onDrop(DropEvent event) { Canvas target = EventHandler.getDragTarget(); SC.say("You dropped the " + target.getID()); } }); Canvas canvas = new Canvas(); canvas.addChild(blue); canvas.addChild(green); canvas.addChild(label); return canvas; } private class DragPiece extends Img { public DragPiece() { setWidth(48); setHeight(48); setCanDrop(true); setCanDrag(true); setDragAppearance(DragAppearance.TRACKER); setAppImgDir("pieces/48/"); } public DragPiece(String src) { this(); super.setSrc(src); } } }