r/org.eclipse.statet.r.ui/src/org/eclipse/statet/internal/r/ui/datafilterview/ScrolledPageComposite.java

/*=============================================================================#
 # Copyright (c) 2012, 2021 Stephan Wahlbrink and others.
 # 
 # This program and the accompanying materials are made available under the
 # terms of the Eclipse Public License 2.0 which is available at
 # https://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
 # which is available at https://www.apache.org/licenses/LICENSE-2.0.
 # 
 # SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
 # 
 # Contributors:
 #     Stephan Wahlbrink <sw@wahlbrink.eu> - initial API and implementation
 #=============================================================================*/

package org.eclipse.statet.internal.r.ui.datafilterview;

import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;
import org.eclipse.ui.forms.FormColors;
import org.eclipse.ui.forms.events.ExpansionAdapter;
import org.eclipse.ui.forms.events.ExpansionEvent;
import org.eclipse.ui.forms.events.IExpansionListener;
import org.eclipse.ui.forms.widgets.FormToolkit;
import org.eclipse.ui.forms.widgets.SharedScrolledComposite;


public class ScrolledPageComposite extends SharedScrolledComposite {
	
	
	private static FormToolkit gDialogsFormToolkit;
	
	private static FormToolkit getViewFormToolkit() {
		if (gDialogsFormToolkit == null) {
			final FormColors colors= new FormColors(Display.getCurrent());
			gDialogsFormToolkit= new FormToolkit(colors);
		}
		return gDialogsFormToolkit;
	}
	
	
	private final FormToolkit toolkit;
	
	private IExpansionListener expansionListener;
	
	private int delayReflowCounter;
	
	
	public ScrolledPageComposite(final Composite parent) {
		this(parent, SWT.H_SCROLL | SWT.V_SCROLL);
	}
	
	public ScrolledPageComposite(final Composite parent, final int style) {
		super(parent, style);
		
		if ((style & SWT.H_SCROLL) == 0) {
			setExpandHorizontal(true);
		}
		
		setFont(parent.getFont());
		
		this.toolkit= getViewFormToolkit();
		
		setExpandHorizontal(true);
		setExpandVertical(true);
		
		final Composite body= new Composite(this, SWT.NONE);
		setContent(body);
		
		setFont(parent.getFont());
		setBackground(this.toolkit.getColors().getBackground());
	}
	
	
	@Override
	public Composite getContent() {
		return (Composite) super.getContent();
	}
	
	@Override
	public void setDelayedReflow(final boolean delayedReflow) {
		if (delayedReflow) {
			this.delayReflowCounter++;
		}
		else {
			this.delayReflowCounter--;
		}
		super.setDelayedReflow(this.delayReflowCounter > 0);
	}
	
	public void adaptChild(final Control childControl) {
		if (childControl instanceof ExpandableRowComposite) {
			this.toolkit.adapt(childControl, true, false);
			if (this.expansionListener == null) {
				this.expansionListener= new ExpansionAdapter() {
					@Override
					public void expansionStateChanged(final ExpansionEvent e) {
						expandedStateChanged();
					}
				};
			}
			((ExpandableRowComposite) childControl).addExpansionListener(this.expansionListener);
		}
		else if (childControl instanceof Composite) {
			this.toolkit.adapt(childControl, false, false);
			final Control[] children= ((Composite) childControl).getChildren();
			for (int i= 0; i < children.length; i++) {
				this.toolkit.adapt(children[i], true, false);
			}
		}
		else {
			this.toolkit.adapt(childControl, true, false);
		}
	}
	
	protected void expandedStateChanged() {
		reflow(true);
	}
	
}