org.eclipse.mylyn.commons.workbench.forms.SectionComposite.java Source code

Introduction

Here is the source code for org.eclipse.mylyn.commons.workbench.forms.SectionComposite.java

Source

/*******************************************************************************
 * Copyright (c) 2010 Tasktop Technologies 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:
 *     Tasktop Technologies - initial API and implementation
 *******************************************************************************/

package org.eclipse.mylyn.commons.workbench.forms;

import org.eclipse.jface.layout.GridDataFactory;
import org.eclipse.jface.layout.GridLayoutFactory;
import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.jface.window.Window;
import org.eclipse.mylyn.internal.commons.ui.WindowUtil;
import org.eclipse.mylyn.internal.commons.workbench.CommonsWorkbenchPlugin;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.DisposeEvent;
import org.eclipse.swt.events.DisposeListener;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.ui.forms.events.ExpansionAdapter;
import org.eclipse.ui.forms.events.ExpansionEvent;
import org.eclipse.ui.forms.widgets.ExpandableComposite;
import org.eclipse.ui.forms.widgets.FormToolkit;
import org.eclipse.ui.forms.widgets.SharedScrolledComposite;

/**
 * @author Steffen Pingel
 * @since 3.7
 */
public class SectionComposite extends SharedScrolledComposite {

    private FormToolkit toolkit;

    private final Composite content;

    public SectionComposite(Composite parent, int style) {
        super(parent, style | SWT.V_SCROLL);
        addDisposeListener(new DisposeListener() {
            public void widgetDisposed(DisposeEvent e) {
                if (toolkit != null) {
                    toolkit.dispose();
                    toolkit = null;
                }
            }
        });
        content = new Composite(this, SWT.NONE);
        content.setLayout(GridLayoutFactory.fillDefaults().create());
        setContent(content);
        content.setBackground(null);
        setExpandVertical(true);
        setExpandHorizontal(true);
    }

    @Override
    public Composite getContent() {
        return content;
    }

    public ExpandableComposite createSection(String title) {
        return createSection(title, SWT.NONE, false);
    }

    public ExpandableComposite createSection(String title, int expansionStyle) {
        return createSection(title, expansionStyle, false);
    }

    public ExpandableComposite createSection(String title, int expansionStyle,
            final boolean grabExcessVerticalSpace) {
        final ExpandableComposite section = getToolkit().createExpandableComposite(getContent(),
                ExpandableComposite.TWISTIE | ExpandableComposite.CLIENT_INDENT | ExpandableComposite.COMPACT
                        | expansionStyle);
        section.titleBarTextMarginWidth = 0;
        section.setBackground(null);
        section.setFont(JFaceResources.getFontRegistry().getBold(JFaceResources.DIALOG_FONT));
        section.addExpansionListener(new ExpansionAdapter() {
            @Override
            public void expansionStateChanged(ExpansionEvent e) {
                if ((Boolean) e.data == true && grabExcessVerticalSpace) {
                    GridData g = (GridData) section.getLayoutData();
                    g.verticalAlignment = GridData.FILL;
                    g.grabExcessVerticalSpace = true;
                    section.setLayoutData(g);
                } else {
                    GridData g = (GridData) section.getLayoutData();
                    g.verticalAlignment = GridData.BEGINNING;
                    g.grabExcessVerticalSpace = false;
                    section.setLayoutData(g);
                }

                resizeAndReflow();
            }
        });
        section.setText(title);
        if (content.getLayout() instanceof GridLayout) {
            GridDataFactory.fillDefaults().indent(0, 5).grab(true, false)
                    .span(((GridLayout) content.getLayout()).numColumns, SWT.DEFAULT).applyTo(section);
        }
        return section;
    }

    public FormToolkit getToolkit() {
        checkWidget();
        if (toolkit == null) {
            toolkit = new FormToolkit(CommonsWorkbenchPlugin.getDefault().getFormColors(getDisplay()));
        }
        return toolkit;
    }

    /**
     * Invokes {@link #layout(boolean)} and resizes the shell if the preferred size of its children is larger than its
     * current size and invokes {@link #reflow(boolean)} to update the scroll bar.
     * <p>
     * This method is invoked when sections are expanded. Clients should invoke this method when the contents of the
     * {@link SectionComposite} are changed.
     * 
     * @since 3.10
     */
    public void resizeAndReflow() {
        layout(true);

        Point newSize = getShell().computeSize(SWT.DEFAULT, SWT.DEFAULT, true);
        Rectangle currentbounds = getShell().getBounds();
        if (newSize.x > currentbounds.width || newSize.y > currentbounds.height) {
            Object shellData = getShell().getData();
            if (shellData instanceof Window) {
                Window window = (Window) shellData;
                Rectangle preferredSize = new Rectangle(currentbounds.x, currentbounds.y,
                        Math.max(currentbounds.width, newSize.x), Math.max(currentbounds.height, newSize.y));
                Rectangle result = WindowUtil.getConstrainedShellBounds(window, preferredSize);
                getShell().setBounds(result);
            }
        }

        reflow(true);
        getParent().layout(true, true);
    }

}