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/*******************************************************************************
* Copyright (c) 2000, 2004 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Common Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/cpl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.swt.custom;
import org.eclipse.swt.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.widgets.*;
/**
* This class provides the layout for ScrolledComposite
*
* @see ScrolledComposite
*/
class ScrolledCompositeLayout extends Layout {
boolean inLayout = false;
static final int DEFAULT_WIDTH = 64;
static final int DEFAULT_HEIGHT = 64;
protected Point computeSize(Composite composite, int wHint, int hHint, boolean flushCache) {
ScrolledComposite sc = (ScrolledComposite)composite;
if (sc.content == null) {
int w = (wHint != SWT.DEFAULT) ? wHint : DEFAULT_WIDTH;
int h = (hHint != SWT.DEFAULT) ? hHint : DEFAULT_HEIGHT;
Rectangle trim = sc.computeTrim(0, 0, w, h);
return new Point(trim.width, trim.height);
}
Point size = sc.content.computeSize (wHint, hHint, flushCache);
if (sc.alwaysShowScroll) {
ScrollBar hBar = sc.getHorizontalBar();
ScrollBar vBar = sc.getVerticalBar();
if (hBar != null) size.y += hBar.getSize().y;
if (vBar != null) size.x += vBar.getSize().x;
}
return size;
}
protected boolean flushCache(Control control) {
return true;
}
protected void layout(Composite composite, boolean flushCache) {
if (inLayout) return;
ScrolledComposite sc = (ScrolledComposite)composite;
if (sc.content == null) return;
inLayout = true;
Rectangle contentRect = sc.content.getBounds();
ScrollBar hBar = sc.getHorizontalBar();
ScrollBar vBar = sc.getVerticalBar();
if (!sc.alwaysShowScroll) {
boolean hVisible = sc.needHScroll(contentRect, false);
boolean vVisible = sc.needVScroll(contentRect, hVisible);
if (!hVisible && vVisible) hVisible = sc.needHScroll(contentRect, vVisible);
if (hBar != null) hBar.setVisible(hVisible);
if (vBar != null) vBar.setVisible(vVisible);
}
Rectangle hostRect = sc.getClientArea();
if (sc.expandHorizontal) {
contentRect.width = Math.max(sc.minWidth, hostRect.width);
}
if (sc.expandVertical) {
contentRect.height = Math.max(sc.minHeight, hostRect.height);
}
if (hBar != null) {
hBar.setMaximum (contentRect.width);
hBar.setThumb (Math.min (contentRect.width, hostRect.width));
int hPage = contentRect.width - hostRect.width;
int hSelection = hBar.getSelection ();
if (hSelection >= hPage) {
if (hPage <= 0) {
hSelection = 0;
hBar.setSelection(0);
}
contentRect.x = -hSelection;
}
}
if (vBar != null) {
vBar.setMaximum (contentRect.height);
vBar.setThumb (Math.min (contentRect.height, hostRect.height));
int vPage = contentRect.height - hostRect.height;
int vSelection = vBar.getSelection ();
if (vSelection >= vPage) {
if (vPage <= 0) {
vSelection = 0;
vBar.setSelection(0);
}
contentRect.y = -vSelection;
}
}
sc.content.setBounds (contentRect);
inLayout = false;
}
}
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