/**
* $Id: mxPanningHandler.java,v 1.1 2012/11/15 13:26:44 gaudenz Exp $
* Copyright (c) 2008, Gaudenz Alder
*/
package com.mxgraph.swing.handler;
import com.mxgraph.swing.mxGraphComponent;
import com.mxgraph.swing.util.mxMouseAdapter;
import java.awt.*;
import java.awt.event.MouseEvent;
/**
*
*/
public class mxPanningHandler extends mxMouseAdapter {
/**
*
*/
private static final long serialVersionUID = 7969814728058376339L;
/**
*
*/
protected mxGraphComponent graphComponent;
/**
*
*/
protected boolean enabled = true;
/**
*
*/
protected transient Point start;
/**
* @param graphComponent
*/
public mxPanningHandler(mxGraphComponent graphComponent) {
this.graphComponent = graphComponent;
graphComponent.getGraphControl().addMouseListener(this);
graphComponent.getGraphControl().addMouseMotionListener(this);
}
/**
*
*/
public boolean isEnabled() {
return enabled;
}
/**
*
*/
public void setEnabled(boolean value) {
enabled = value;
}
/**
*
*/
public void mousePressed(MouseEvent e) {
if (isEnabled() && !e.isConsumed() && graphComponent.isPanningEvent(e) && !e.isPopupTrigger()) {
start = e.getPoint();
}
}
/**
*
*/
public void mouseDragged(MouseEvent e) {
if (!e.isConsumed() && start != null) {
int dx = e.getX() - start.x;
int dy = e.getY() - start.y;
Rectangle r = graphComponent.getViewport().getViewRect();
int right = r.x + ((dx > 0) ? 0 : r.width) - dx;
int bottom = r.y + ((dy > 0) ? 0 : r.height) - dy;
graphComponent.getGraphControl().scrollRectToVisible(new Rectangle(right, bottom, 0, 0));
e.consume();
}
}
/**
*
*/
public void mouseReleased(MouseEvent e) {
if (!e.isConsumed() && start != null) {
int dx = Math.abs(start.x - e.getX());
int dy = Math.abs(start.y - e.getY());
if (graphComponent.isSignificant(dx, dy)) {
e.consume();
}
}
start = null;
}
/**
* Whether or not panning is currently active
*
* @return Whether or not panning is currently active
*/
public boolean isActive() {
return (start != null);
}
}