platform.window:invalidate is a function that is part of platform.window.
This routine invalidates a region of the window by firing the on.paint event, thus forcing it get repainted.
x and y default to (0, 0) and width and height default to the pixel width and height of the window.
These arguments are optional.
This has been introduced in TI-Nspire OS 3.0 (Changes).
platform.window:invalidate([x, y, width, height])
|number||x-coordinate of the upper-left origin.|
|number||y-coordinate of the upper-left origin.|
|number||width of the region to be refreshed.|
|number||height of the region to be refreshed.|
platform.window:invalidate(0, 0, 50, 10)
Good to know
The entire window can be forced to repaint with by calling the function with no arguments : platform.window:invalidate() , allowing all parameters to take their default values.
Repainting only a part of the widget (thanks to providing the necessary arguments) only currently works on-calc, not on the software.