org.eclipse.swt.snippets.Snippet162.java Source code

Introduction

Here is the source code for org.eclipse.swt.snippets.Snippet162.java

Source

/*******************************************************************************
 * Copyright (c) 2016 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
 *     Lars Vogel <Lars.Vogel@vogella.com> - Bug 502845
 *******************************************************************************/
package org.eclipse.swt.snippets;

/*
 * Adding an accessible listener to provide emulated state information
 *
 * For a list of all SWT example snippets see
 * http://www.eclipse.org/swt/snippets/
 */

import static org.eclipse.swt.events.SelectionListener.*;

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

public class Snippet162 {

    final static String[] ITEM_NAMES = { "first item", "second", "third", "fourth", "fifth" };

    public static void main(String[] args) {
        Display display = new Display();
        final Image checkedImage = getStateImage(display, true);
        final Image uncheckedImage = getStateImage(display, false);

        Shell shell = new Shell(display);
        shell.setText("Snippet 162");
        shell.setLayout(new FillLayout());

        final Table table = new Table(shell, SWT.FULL_SELECTION | SWT.BORDER);
        for (int i = 0; i < ITEM_NAMES.length; i++) {
            TableItem item = new TableItem(table, SWT.NONE);
            item.setText(ITEM_NAMES[i]);
            item.setImage(i % 2 == 0 ? checkedImage : uncheckedImage);
        }
        table.addSelectionListener(widgetDefaultSelectedAdapter(e -> {
            TableItem item = (TableItem) e.item;
            item.setImage(item.getImage() == checkedImage ? uncheckedImage : checkedImage);
        }));

        table.getAccessible().addAccessibleControlListener(new AccessibleControlAdapter() {
            @Override
            public void getRole(AccessibleControlEvent e) {
                e.detail = ACC.ROLE_CHECKBUTTON;
            }

            @Override
            public void getState(AccessibleControlEvent e) {
                if (e.childID >= 0 && e.childID < table.getItemCount()) {
                    TableItem item = table.getItem(e.childID);
                    if (item.getImage() == checkedImage) {
                        e.detail |= ACC.STATE_CHECKED;
                    }
                }
            }
        });

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

    static Image getStateImage(Display display, boolean checked) {
        Image image = new Image(display, 16, 16);
        GC gc = new GC(image);
        gc.setBackground(display.getSystemColor(SWT.COLOR_YELLOW));
        gc.fillOval(0, 0, 16, 16);
        if (checked) {
            gc.setForeground(display.getSystemColor(SWT.COLOR_DARK_GREEN));
            gc.drawLine(0, 0, 16, 16);
            gc.drawLine(16, 0, 0, 16);
        }
        gc.dispose();
        return image;
    }
}