Snippet21.java Source code

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Here is the source code for Snippet21.java

Source

/*
 * Canvas example snippet: implement tab traversal (behave like a tab group)
 *
 * For a list of all SWT example snippets see
 * http://dev.eclipse.org/viewcvs/index.cgi/%7Echeckout%7E/platform-swt-home/dev.html#snippets
 */
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Canvas;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Text;

public class Snippet21 {

    public static void main(String[] args) {
        Display display = new Display();
        final Color red = display.getSystemColor(SWT.COLOR_RED);
        final Color blue = display.getSystemColor(SWT.COLOR_BLUE);
        Shell shell = new Shell(display);
        Button b = new Button(shell, SWT.PUSH);
        b.setBounds(10, 10, 100, 32);
        b.setText("Button");
        shell.setDefaultButton(b);
        final Canvas c = new Canvas(shell, SWT.BORDER);
        c.setBounds(10, 50, 100, 32);
        c.addListener(SWT.Traverse, new Listener() {
            public void handleEvent(Event e) {
                switch (e.detail) {
                /* Do tab group traversal */
                case SWT.TRAVERSE_ESCAPE:
                case SWT.TRAVERSE_RETURN:
                case SWT.TRAVERSE_TAB_NEXT:
                case SWT.TRAVERSE_TAB_PREVIOUS:
                case SWT.TRAVERSE_PAGE_NEXT:
                case SWT.TRAVERSE_PAGE_PREVIOUS:
                    e.doit = true;
                    break;
                }
            }
        });
        c.addListener(SWT.FocusIn, new Listener() {
            public void handleEvent(Event e) {
                c.setBackground(red);
            }
        });
        c.addListener(SWT.FocusOut, new Listener() {
            public void handleEvent(Event e) {
                c.setBackground(blue);
            }
        });
        c.addListener(SWT.KeyDown, new Listener() {
            public void handleEvent(Event e) {
                System.out.println("KEY");
                for (int i = 0; i < 64; i++) {
                    Color c1 = red, c2 = blue;
                    if (c.isFocusControl()) {
                        c1 = blue;
                        c2 = red;
                    }
                    c.setBackground(c1);
                    c.update();
                    c.setBackground(c2);
                }
            }
        });
        Text t = new Text(shell, SWT.SINGLE | SWT.BORDER);
        t.setBounds(10, 85, 100, 32);

        Text r = new Text(shell, SWT.MULTI | SWT.BORDER);
        r.setBounds(10, 120, 100, 32);

        c.setFocus();
        shell.setSize(200, 200);
        shell.open();
        while (!shell.isDisposed()) {
            if (!display.readAndDispatch())
                display.sleep();
        }
        display.dispose();
    }
}