org.eclipse.swt.snippets.Snippet232.java Source code

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Here is the source code for org.eclipse.swt.snippets.Snippet232.java

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/*******************************************************************************
 * Copyright (c) 2000, 2013 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.swt.snippets;

/*
 * Tree example snippet: show results as a bar chart in tree
 *
 * For more info on custom-drawing TableItem and TreeItem content see
 * http://www.eclipse.org/articles/article.php?file=Article-CustomDrawingTableAndTreeItems/index.html
 *
 * For a list of all SWT example snippets see
 * http://www.eclipse.org/swt/snippets/
 *
 * @since 3.2
 */

import org.eclipse.swt.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.layout.*;
import org.eclipse.swt.widgets.*;

public class Snippet232 {

    public static void main(String[] args) {
        final Display display = new Display();
        Shell shell = new Shell(display);
        shell.setLayout(new FillLayout());
        shell.setText("Show results as a bar chart in Tree");
        final Tree tree = new Tree(shell, SWT.BORDER);
        tree.setHeaderVisible(true);
        tree.setLinesVisible(true);
        TreeColumn column1 = new TreeColumn(tree, SWT.NONE);
        column1.setText("Bug Status");
        column1.setWidth(100);
        final TreeColumn column2 = new TreeColumn(tree, SWT.NONE);
        column2.setText("Percent");
        column2.setWidth(200);
        String[] states = new String[] { "Resolved", "New", "Won't Fix", "Invalid" };
        String[] teams = new String[] { "UI", "SWT", "OSGI" };
        for (int i = 0; i < teams.length; i++) {
            TreeItem item = new TreeItem(tree, SWT.NONE);
            item.setText(teams[i]);
            for (int j = 0; j < states.length; j++) {
                TreeItem subItem = new TreeItem(item, SWT.NONE);
                subItem.setText(states[j]);
            }
        }

        /*
         * NOTE: MeasureItem, PaintItem and EraseItem are called repeatedly.
         * Therefore, it is critical for performance that these methods be
         * as efficient as possible.
         */
        tree.addListener(SWT.PaintItem, new Listener() {
            int[] percents = new int[] { 50, 30, 5, 15 };

            @Override
            public void handleEvent(Event event) {
                if (event.index == 1) {
                    TreeItem item = (TreeItem) event.item;
                    TreeItem parent = item.getParentItem();
                    if (parent != null) {
                        GC gc = event.gc;
                        int index = parent.indexOf(item);
                        int percent = percents[index];
                        Color foreground = gc.getForeground();
                        Color background = gc.getBackground();
                        gc.setForeground(display.getSystemColor(SWT.COLOR_RED));
                        gc.setBackground(display.getSystemColor(SWT.COLOR_YELLOW));
                        int width = (column2.getWidth() - 1) * percent / 100;
                        gc.fillGradientRectangle(event.x, event.y, width, event.height, true);
                        Rectangle rect2 = new Rectangle(event.x, event.y, width - 1, event.height - 1);
                        gc.drawRectangle(rect2);
                        gc.setForeground(display.getSystemColor(SWT.COLOR_LIST_FOREGROUND));
                        String text = percent + "%";
                        Point size = event.gc.textExtent(text);
                        int offset = Math.max(0, (event.height - size.y) / 2);
                        gc.drawText(text, event.x + 2, event.y + offset, true);
                        gc.setForeground(background);
                        gc.setBackground(foreground);
                    }
                }
            }
        });

        shell.pack();
        shell.open();
        while (!shell.isDisposed()) {
            if (!display.readAndDispatch())
                display.sleep();
        }
        display.dispose();
    }
}