[news.eclipse.platform.swt] Relative sizing and scaling with a FormLayou

[adam.preble@xxxxxxxxx (Adam Preble)]

I have been doing some charting with canvases.  Right now, most of the 
chart is done in its own composite, with the x-axis hanging on outside of 
that.  The idea is eventually I might have two charts sharing one x-axis, 
so that's why I have it excluded.  But this is making drawing the final 
chart a little strange to me.  I'm still new to my layouts, so keep that 
in mind.

Here's the snippet doing the work:

		FormLayout chartLayout = new FormLayout();
		
		Composite chart1Comp = new Composite(shell, SWT.PUSH);
		Composite xAxis		 = new Composite(shell, SWT.PUSH);
		
		// chart1 and bottom are set here
		chart1 = new FinancialLineChart(this, chart1Comp, display, data);
		bottom = new XAxis(0, data[0].size(), xAxis, display);

		FormData chart1Form = new FormData();
		chart1Form.top = new FormAttachment(0, 0);		
		chart1Form.bottom = new FormAttachment(0, 299);  
		chart1Form.left = new FormAttachment(0, 0);		
		chart1Form.right = new FormAttachment(100, 0);	
		chart1Comp.setLayoutData(chart1Form);

		FormData xAxisForm = new FormData();
		
		xAxisForm.top = new FormAttachment(chart1Comp, 0);
		xAxisForm.bottom = new FormAttachment(0, 399);  	 
		xAxisForm.left = new FormAttachment(0, 99);		
		xAxisForm.right = new FormAttachment(100, -150);	
		xAxis.setLayoutData(xAxisForm);

		shell.setLayout(chartLayout);

So the x-axis starts 300 pixels down and a little bit indented on either 
side since it only draws across the actual plotting area.  This is one 
reason I was using a FormLayout.  The other was the x-axis doesn't have to 
be as large as the charting body, which the layouts that do vertical 
scaling like to keep equal.

If I expand the window to the right, everything scales fine.  If I try to 
expand vertically, nothing scales.  My listener for the chart is called 
but it cannot expand since it doesn't get a larger drawing area.  It seems 
like my x-axis there is pinning it in.  Is there a way to get the layout 
to appropriately scale everything?  I don't want the x-axis to get larger 
vertically, rather the chart body should expand.  Or do I have to code a 
PaintListener for this object?