Determine the dimensions of a Dojo Widget

My objective is to build a Dojo widget that embeds some graphic information, for example an Analogue Gauge, along with some other st开发者_开发百科uff.

I have managed to build a widget and initialise the Analogue widget with code such as:

    gauge = new dojox.widget.AnalogGauge({
                id: "defaultGauge",
                width: 300,
                height: 200,
                cx: 150,
                cy: 175,
                radius: 125,

Now I've generalised this so that the width, height, cx, cy and radius can be calculated if I know the dimensions in which the widget will be rendered. Say for example, it's going to be in the "top" region of a Border Layout of height 150px, then I can compute suitable values.

The question: how do I determine the available space for my widget to work in? Is there some API by which I can obtain this information from the Layout or Content Pane?

It seems that the widget can provide a

  resize(dimensions) 

method, which is called both when the widget is first displayed and also when it is resized. The argument being an object holding the width and height of the display area.

Hence if the

gauge = new dojox.widget.AnalogGauge({

code is moved into the resize method we can provide suitable size information to the gauge constructor. I have yet to understand how to deal with subsequent resize() requests.