/*******************************************************************************
* Copyright (c) 2004, 2006 IBM Corporation and others.
* 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:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.ui.tests.performance.layout;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Layout;
/**
* A very efficient (but useless) layout with complicated preferred size behavior.
* Its preferred size attempts to maintain a constant area. This can be used for
* performance testing other layouts (by attaching this to child Composites in the
* layout being tested). It will give a good estimate as to how the layout will
* handle wrapping widgets.
*
* @since 3.1
*/
public class ConstantAreaLayout extends Layout {
private int area;
private int preferredWidth;
public ConstantAreaLayout(int area, int preferredWidth) {
this.area = area;
this.preferredWidth = preferredWidth;
}
@Override
protected Point computeSize(Composite composite, int wHint, int hHint,
boolean flushCache) {
if (wHint == 0 || hHint == 0) {
return new Point(1,1);
}
if (wHint == SWT.DEFAULT) {
if (hHint == SWT.DEFAULT) {
wHint = preferredWidth;
} else {
wHint = area / hHint;
}
}
if (hHint == SWT.DEFAULT) {
hHint = area / wHint;
}
return new Point(wHint, hHint);
}
@Override
protected void layout(Composite composite, boolean flushCache) {
}
}