transparent

Topic group Related topics

Specifies whether an object’s background is painted to simulate transparency.

Property of

CheckBox, Container, Image, ListBox, PaintBox, RadioButton, Rectangle, Text, TextLabel

Description

Setting an object’s transparent property to true marks the object to be painted to appear to be transparent. A form's (or subform's) doubleBuffered property affects how the object's background is painted to achieve transparency.

When doubleBuffered is False, the default, a transparent component's background takes on the background color, or image, of its container, making the background appear to be transparent. Note that the background is not actually transparent; if the control overlaps another control, you will still see the background of the container, not the portion of the control that has been overlapped.

When doubleBuffered is True, transparent components are painted to appear almost fully transparent allowing overlapped components to be visible through the transparent control. In order to achieve this level of transparency, doubleBuffered forms are painted back to front (according to their z-order) to simulate true transparency. This painting is done first to an off screen buffer and than displayed when all the layers have been painted. This allows for a more complete transparency effect, but causes forms to paint more slowly compared to leaving doubleBuffered set to False.