org.eclipse.swt.snippets.Snippet51.java Source code

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Here is the source code for org.eclipse.swt.snippets.Snippet51.java

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/*******************************************************************************
 * Copyright (c) 2000, 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
 *******************************************************************************/
package org.eclipse.swt.snippets;

/*
 * SWT Table snippet: scroll a Table one "page" at a time.
 *
 * For a list of all SWT example snippets see
 * http://www.eclipse.org/swt/snippets/
 */
import org.eclipse.swt.*;
import org.eclipse.swt.layout.*;
import org.eclipse.swt.widgets.*;

public class Snippet51 {

    public static void main(String[] args) {
        Display display = new Display();
        Shell shell = new Shell(display);
        shell.setText("Snippet 51");
        shell.setBounds(10, 10, 300, 300);
        shell.setLayout(new GridLayout(2, true));
        final Table table = new Table(shell, SWT.NONE);
        GridData data = new GridData(GridData.FILL_BOTH);
        data.horizontalSpan = 2;
        table.setLayoutData(data);
        for (int i = 0; i < 99; i++) {
            new TableItem(table, SWT.NONE).setText("item " + i);
        }
        Button upButton = new Button(shell, SWT.PUSH);
        upButton.setText("Scroll up one page");
        upButton.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, false));
        upButton.addListener(SWT.Selection, event -> {
            int height = table.getClientArea().height;
            int visibleItemCount = height / table.getItemHeight();
            int topIndex = table.getTopIndex();
            int newTopIndex = Math.max(0, topIndex - visibleItemCount);
            if (topIndex != newTopIndex) {
                table.setTopIndex(newTopIndex);
            }
        });
        Button downButton = new Button(shell, SWT.PUSH);
        downButton.setText("Scroll down one page");
        downButton.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, false));
        downButton.addListener(SWT.Selection, event -> {
            int height = table.getClientArea().height;
            int visibleItemCount = height / table.getItemHeight();
            int topIndex = table.getTopIndex();
            int newTopIndex = Math.min(table.getItemCount(), topIndex + visibleItemCount);
            if (topIndex != newTopIndex) {
                table.setTopIndex(newTopIndex);
            }
        });
        shell.open();
        while (!shell.isDisposed()) {
            if (!display.readAndDispatch())
                display.sleep();
        }
        display.dispose();
    }

}