Click and drag to pan the image inside its frame. (Smart GWT) : Drag Drop « GWT « Java
Click and drag to pan the image inside its frame. (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.Cursor;
import com.smartgwt.client.types.DragAppearance;
import com.smartgwt.client.types.ImageStyle;
import com.smartgwt.client.types.Overflow;
import com.smartgwt.client.util.EventHandler;
import com.smartgwt.client.widgets.Canvas;
import com.smartgwt.client.widgets.Img;
import com.smartgwt.client.widgets.events.DragMoveEvent;
import com.smartgwt.client.widgets.events.DragMoveHandler;
import com.smartgwt.client.widgets.events.DragStartEvent;
import com.smartgwt.client.widgets.events.DragStartHandler;
public class Showcase implements EntryPoint {
public void onModuleLoad() {
RootPanel.get().add(getViewPanel());
}
public Canvas getViewPanel() {
Canvas canvas = new Canvas();
canvas.addChild(new DragPanSampleImg());
return canvas;
}
}
class DragPanSampleImg extends Img {
private int startScrollLeft;
private int startScrollTop;
public DragPanSampleImg() {
super("other/cpu.jpg", 200, 200);
setLeft(50);
setTop(50);
setOverflow(Overflow.HIDDEN);
setShowEdges(true);
setPadding(20);
setImageType(ImageStyle.NORMAL);
setCanDrag(true);
setCursor(Cursor.ALL_SCROLL);
setDragAppearance(DragAppearance.NONE);
addDragStartHandler(new DragStartHandler() {
public void onDragStart(DragStartEvent event) {
startScrollLeft = getScrollLeft();
startScrollTop = getScrollTop();
}
});
addDragMoveHandler(new DragMoveHandler() {
public void onDragMove(DragMoveEvent event) {
int left = startScrollLeft - EventHandler.getX() + EventHandler.getMouseDownX();
int top = startScrollTop - EventHandler.getY() + EventHandler.getMouseDownY();
scrollTo(left, top);
}
});
}
}
SmartGWT.zip( 9,880 k)
