Graphics.Height
From Xojo Documentation
Read-Only Property (As Integer )
The height in pixels of the parent object, typically a Canvas control or a Window.
Notes
For example, if the graphics class object is in a Canvas control, Height returns the height of the control.
Example
This example in the Canvas.Paint event draws a box the height of the Canvas itself:
g.DrawingColor = &c0000ff
g.FillRectangle(0, 0, g.Width, g.Height)
g.FillRectangle(0, 0, g.Width, g.Height)