What TChart.Canvas class is being used?

[TestAlways]

For a long time, I had the following code:

Code: Select all

  Assert(aChart.Canvas is TGDIPlusCanvas, 'Chart canvas class should be TGDIPlusCanvas but is ' + aChart.Canvas.ClassName);
  aChart.Canvas := TTeeCanvas3D.Create;
  try
  ...
  finally
    aChart.Canvas := TGDIPlusCanvas.Create;
  end;

This code gets called a lot (used to create an image of a chart for reporting). But a few days ago the Assert fired.

How can I know what class is used by default for the TChart.Canvas object?

Ed Dressel

[Yeray]

Hi Ed,

The default Canvas is the one you have selected in the "Render" combobox at the "New Chart" tab at the design time options. Note this option is saved at the registry entry:

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HKEY_CURRENT_USER\Software\Steema Software\TeeChart Pro\Editor\DefaultCanvas

- a blank string '' is the value set for the GDI canvas.
- 'TGDIPlusCanvas' is the value set for GDI+.