/*
 * Copyright (C) 2002-@year@ by University of Maryland, College Park, MD 20742, USA
 * All rights reserved.
 *
 * Piccolo was written at the Human-Computer Interaction Laboratory
 * www.cs.umd.edu/hcil by Jesse Grosjean under the supervision of Ben Bederson.
 * The Piccolo website is www.cs.umd.edu/hcil/piccolo
 */
package edu.umd.cs.piccolox.swt;

import java.awt.event.ActionListener;
import javax.swing.Timer;

import org.eclipse.swt.widgets.Composite;

import edu.umd.cs.piccolo.PRoot;

/**
 * <b>PSWTRoot</b> is a subclass of PRoot that is designed to work in the SWT
 * environment. In particular it uses SWTTimers and the SWT event dispatch
 * thread. With the current setup only a single PSWTCanvas is expected to be
 * connected to a root.
 * <P>
 * 
 * @version 1.1
 * @author Jesse Grosjean
 */
public class PSWTRoot extends PRoot {

    private Composite composite;

    public PSWTRoot(Composite composite) {
        this.composite = composite;
    }

    public Timer createTimer(int delay, ActionListener listener) {
        return new SWTTimer(composite.getDisplay(), delay, listener);
    }

    public void scheduleProcessInputsIfNeeded() {
        if (!Thread.currentThread().equals(composite.getDisplay().getThread())) {
            return;
        }

        if (!processInputsScheduled && !processingInputs
                && (getFullBoundsInvalid() || getChildBoundsInvalid() || getPaintInvalid() || getChildPaintInvalid())) {

            processInputsScheduled = true;
            composite.getDisplay().asyncExec(new Runnable() {
                public void run() {
                    processInputs();
                    processInputsScheduled = false;
                }
            });
        }
    }
}