org.kalypso.contribs.eclipse.jface.viewers.ViewerUtilities.java Source code

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Here is the source code for org.kalypso.contribs.eclipse.jface.viewers.ViewerUtilities.java

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/*--------------- Kalypso-Header ------------------------------------------
    
 This file is part of kalypso.
 Copyright (C) 2004, 2005 by:
    
 Technical University Hamburg-Harburg (TUHH)
 Institute of River and coastal engineering
 Denickestr. 22
 21073 Hamburg, Germany
 http://www.tuhh.de/wb
    
 and
    
 Bjoernsen Consulting Engineers (BCE)
 Maria Trost 3
 56070 Koblenz, Germany
 http://www.bjoernsen.de
    
 This library is free software; you can redistribute it and/or
 modify it under the terms of the GNU Lesser General Public
 License as published by the Free Software Foundation; either
 version 2.1 of the License, or (at your option) any later version.
    
 This library is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 Lesser General Public License for more details.
    
 You should have received a copy of the GNU Lesser General Public
 License along with this library; if not, write to the Free Software
 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
    
 Contact:
    
 E-Mail:
 belger@bjoernsen.de
 schlienger@bjoernsen.de
 v.doemming@tuhh.de
    
 --------------------------------------------------------------------------*/
package org.kalypso.contribs.eclipse.jface.viewers;

import org.eclipse.jface.viewers.ContentViewer;
import org.eclipse.jface.viewers.IContentProvider;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.jface.viewers.IStructuredContentProvider;
import org.eclipse.jface.viewers.StructuredSelection;
import org.eclipse.jface.viewers.StructuredViewer;
import org.eclipse.jface.viewers.TreeViewer;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;

/**
 * Utility methods for {@link org.eclipse.jface.viewers.Viewer}'s.
 * 
 * @author Gernot Belger
 */
public final class ViewerUtilities {
    /** Never gets instantiated */
    private ViewerUtilities() {
        // never instantiate it
    }

    /**
     * Sets the selection of this viewer to its first input-element.
     * <p>
     * The content provider must be a {@link IStructuredContentProvider}.
     * </p>
     */
    public static void selectFirstElement(final ContentViewer viewer) {
        final IContentProvider contentProvider = viewer.getContentProvider();
        if (contentProvider instanceof IStructuredContentProvider) {
            final IStructuredContentProvider provider = (IStructuredContentProvider) contentProvider;
            final Object[] elements = provider.getElements(viewer.getInput());
            if (elements != null && elements.length > 0)
                viewer.setSelection(new StructuredSelection(elements[0]), true);
        }
    }

    public static void execute(final Viewer viewer, final Runnable runner, final boolean async) {
        if (viewer == null)
            return;

        final Control control = viewer.getControl();
        if (control == null || control.isDisposed())
            return;

        final Display display = control.getDisplay();

        if (async)
            display.asyncExec(runner);
        else
            display.syncExec(runner);
    }

    /**
     * Sets the input of a {@link Viewer}in the display thread of its underlying control. Does nothing if the viewer is
     * null, or its control is disposed.
     * 
     * @param async
     *          if true, refresh is done asynchronously, else refresh is done synchronously.
     * @see Viewer#setInput(java.lang.Object )
     * @see Display#asyncExec(java.lang.Runnable)
     * @see Display#syncExec(java.lang.Runnable)
     */
    public static void setInput(final Viewer viewer, final Object input, final boolean async) {
        final Runnable runner = new Runnable() {
            @Override
            public void run() {
                if (!viewer.getControl().isDisposed())
                    viewer.setInput(input);
            }
        };

        execute(viewer, runner, async);
    }

    /**
     * Refresh a {@link Viewer}in the display thread of its underlying control. Does nothing if the viewer is null, or its
     * control is disposed.
     * 
     * @param async
     *          if true, refresh is done asynchronously, else refresh is done synchronously.
     * @see Viewer#refresh()
     * @see Display#asyncExec(java.lang.Runnable)
     * @see Display#syncExec(java.lang.Runnable)
     */
    public static void refresh(final Viewer viewer, final boolean async) {
        final Runnable runner = new Runnable() {
            @Override
            public void run() {
                if (!viewer.getControl().isDisposed())
                    viewer.refresh();
            }
        };

        execute(viewer, runner, async);
    }

    public static void refresh(final StructuredViewer viewer, final Object element, final boolean async) {
        final Runnable runner = new Runnable() {
            @Override
            public void run() {
                if (!viewer.getControl().isDisposed())
                    viewer.refresh(element);
            }
        };

        execute(viewer, runner, async);
    }

    public static void update(final StructuredViewer viewer, final Object[] elements, final String[] properties,
            final boolean async) {
        final Runnable runner = new Runnable() {
            @Override
            public void run() {
                if (!viewer.getControl().isDisposed())
                    viewer.update(elements, properties);
            }
        };

        execute(viewer, runner, async);
    }

    public static void setSelection(final TreeViewer viewer, final ISelection selection, final boolean reveal,
            final boolean async) {
        final Runnable runner = new Runnable() {
            @Override
            public void run() {
                if (!viewer.getControl().isDisposed())
                    viewer.setSelection(selection, reveal);
            }
        };

        execute(viewer, runner, async);
    }
}