Hi Jinho,
yes, the area will be drawn, but the Graphics Engine will remove the drawing instruction for the text item, because it is completely covered by another view.
This means, the Mosaic framework will evaluate all views and prepare the instructions for the Graphics Engine. The Graphics Engine will then process all instructions and optimize them in order to remove all unnecessary drawing instructions.
Example: You have a text object that is completly covered by an opaque rectangle. If the text object causes an invalid area (e.g. by changing the text or by changing the Visible property), the Mosaic framework will create drawing instructions for all views within this area: This means, first the text has to be drawn, then the rectangle has to be drawn. The Graphics Engine will evaluate the sequence of drawing instructions and remove the text drawing insruction, because it has no relevance for the final appearance. As a result, only the rectangle will be drawn.
In this case, the final appearance on the screen will not change, but this cannot be foreseen by the Mosaic.
Best regards,
Manfred.