Snippet46.java Source code

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Here is the source code for Snippet46.java

Source

/*
 * Composite example snippet: intercept mouse events (drag a button with the mouse)
 *
 * 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.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.layout.FillLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Shell;

public class Snippet46 {
    public static void main(String[] args) {
        Display display = new Display();
        final Shell shell = new Shell(display);
        final Composite composite = new Composite(shell, SWT.NONE);
        composite.setEnabled(false);
        composite.setLayout(new FillLayout());
        Button button = new Button(composite, SWT.PUSH);
        button.setText("Button");
        composite.pack();
        composite.setLocation(10, 10);
        final Point[] offset = new Point[1];
        Listener listener = new Listener() {
            public void handleEvent(Event event) {
                switch (event.type) {
                case SWT.MouseDown:
                    Rectangle rect = composite.getBounds();
                    if (rect.contains(event.x, event.y)) {
                        Point pt1 = composite.toDisplay(0, 0);
                        Point pt2 = shell.toDisplay(event.x, event.y);
                        offset[0] = new Point(pt2.x - pt1.x, pt2.y - pt1.y);
                    }
                    break;
                case SWT.MouseMove:
                    if (offset[0] != null) {
                        Point pt = offset[0];
                        composite.setLocation(event.x - pt.x, event.y - pt.y);
                    }
                    break;
                case SWT.MouseUp:
                    offset[0] = null;
                    break;
                }
            }
        };
        shell.addListener(SWT.MouseDown, listener);
        shell.addListener(SWT.MouseUp, listener);
        shell.addListener(SWT.MouseMove, listener);
        shell.setSize(300, 300);
        shell.open();
        while (!shell.isDisposed()) {
            if (!display.readAndDispatch())
                display.sleep();
        }
        display.dispose();
    }
}