An example demonstrating the use of WPaintedWidget with the PaintUpdate rendering flag.

In some cases, you would like to update the canvas without clearing the previously painted contents (which is the default behavior). You may do this by passing the PaintUpdate rendering flag to the update() method.

This example demonstrates this by implementing a simple painting device. The example is quite silly on its own: it sends every mouse drag operation to the server, which in turn updates the canvas. But you could imagine more interesting uses, such as a multi-user white board, or interactive visualizations.

The example uses a custom cursor image (pencil), this is done by providing a cursor image to WCssDecorationStyle.