Bug 179279

Description Markus Keller 2007-03-26 07:00:26 EDT

I20070323-1616

A Tree with a PaintItem listener only shows a horizontal scrollbar if MeasureItem is also hooked:

public class SnippetNoHScrollbar {

public static void main(String[] args) {
	final Display display = new Display();
	final Shell shell = new Shell(display);
	shell.setLayout (new FillLayout());
	
	final Tree tree= new Tree(shell, SWT.MULTI);
	for (int i= 0; i < 21; i++) {
		TreeItem item= new TreeItem(tree, SWT.NONE);
		item.setText("Item with long name" + i);
		
		for (int j= 0; j < 11; j++) {
			TreeItem subItem= new TreeItem(item, SWT.NONE);
			subItem.setText("SubItem " + j);
		}
	}
	final Color red= display.getSystemColor(SWT.COLOR_RED);
	tree.addListener(SWT.PaintItem, new Listener() {
		public void handleEvent(Event e) {
			e.gc.setForeground(red);
			e.gc.drawRectangle(e.x + 1, e.y + 1, e.width - 3, e.height - 3);
		}
	});
//	tree.addListener(SWT.MeasureItem, new Listener() {
//		public void handleEvent(Event e) {
//			// uncomment to make horizontal scrollbar appear ...
//		}
//	});
	
	shell.setSize(50, 300);
	shell.open();
	while (!shell.isDisposed ()) {
		if (!display.readAndDispatch ()) display.sleep ();
	}
	display.dispose ();
}
}