/*******************************************************************************
* Copyright (c) 2011 Laurent CARON
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* Laurent CARON (laurent.caron at gmail dot com) - initial API and implementation
*******************************************************************************/
package org.mihalis.opal.panels;
import org.eclipse.swt.SWT;
import org.eclipse.swt.SWTException;
import org.eclipse.swt.events.PaintEvent;
import org.eclipse.swt.events.PaintListener;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Canvas;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Shell;
/**
* Instances of this class are controls located on the top of a shell. They
* display a dark panel on this shell
*/
public class DarkPanel {
private final Shell parent;
private static final String DARK_PANEL_KEY = "org.mihalis.opal.BluredPanel.DarkPanel";
private int alpha;
private Shell panel;
private Canvas canvas;
/**
* Constructs a new instance of this class given its parent.
*
* @param shell a shell that will be the parent of the new instance (cannot
* be null)
* @exception IllegalArgumentException <ul>
* <li>ERROR_NULL_ARGUMENT - if the parent is null</li>
* </ul>
* @exception SWTException <ul>
* <li>ERROR_WIDGET_DISPOSED - if the parent has been
* disposed</li>
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the
* thread that created the parent</li>
* </ul>
*/
public DarkPanel(final Shell shell) {
if (shell == null) {
SWT.error(SWT.ERROR_NULL_ARGUMENT);
}
if (shell.isDisposed()) {
SWT.error(SWT.ERROR_INVALID_ARGUMENT);
}
this.parent = shell;
if (shell.getData(DARK_PANEL_KEY) != null) {
throw new IllegalArgumentException("This shell has already an infinite panel attached on it !");
}
shell.setData(DARK_PANEL_KEY, this);
this.alpha = 100;
}
/**
* Show the dark panel
*/
public void show() {
if (this.parent.isDisposed()) {
SWT.error(SWT.ERROR_WIDGET_DISPOSED);
}
this.panel = new Shell(this.parent, SWT.APPLICATION_MODAL | SWT.NO_TRIM);
this.panel.setLayout(new FillLayout());
this.panel.setAlpha(this.alpha);
this.panel.addListener(SWT.KeyUp, new Listener() {
@Override
public void handleEvent(final Event event) {
event.doit = false;
}
});
this.canvas = new Canvas(this.panel, SWT.NO_BACKGROUND | SWT.DOUBLE_BUFFERED);
this.canvas.addPaintListener(new PaintListener() {
@Override
public void paintControl(final PaintEvent e) {
paintCanvas(e);
}
});
this.panel.setBounds(this.panel.getDisplay().map(this.parent, null, this.parent.getClientArea()));
this.panel.open();
}
/**
* Paint the canvas that holds the panel
*
* @param e {@link PaintEvent}
*/
private void paintCanvas(final PaintEvent e) {
// Paint the panel
final Rectangle clientArea = ((Canvas) e.widget).getClientArea();
final GC gc = e.gc;
gc.setBackground(this.panel.getDisplay().getSystemColor(SWT.COLOR_BLACK));
gc.fillRectangle(clientArea);
}
/**
* Hide the dark panel
*/
public void hide() {
if (this.parent.isDisposed()) {
SWT.error(SWT.ERROR_WIDGET_DISPOSED);
}
if (this.panel == null || this.panel.isDisposed()) {
return;
}
this.panel.dispose();
}
/**
* @return the alpha value
*/
public int getAlpha() {
return this.alpha;
}
/**
* @param alpha the alpha to set
*/
public void setAlpha(final int alpha) {
this.alpha = alpha;
}
}