ClipDrawable

ClipDrawable is a wrapper drawable in the Android framework that clips its contained drawable according to the current level. It allows partially displaying a child drawable by specifying a clipping direction and an anchor edge. The visible portion is determined by the level value, which ranges from 0 to 10000, where 0 shows nothing and 10000 shows the full drawable.

The clipping behavior depends on two configuration parameters: orientation and gravity. The clipOrientation can be horizontal or vertical, controlling the direction in which the drawable is revealed. Gravity specifies the edge from which clipping begins (for example, left or top when revealing horizontally or vertically). As the level changes, ClipDrawable recalculates the clipping rectangle and draws only the portion of the wrapped drawable that falls within that region.

ClipDrawable can be used both programmatically and in XML. In XML, it is declared as a clip-drawable with attributes such as android:drawable to provide the wrapped drawable, android:clipOrientation to set the direction, and android:gravity to set the anchor edge. Programmatically, you can construct it with a drawable, gravity, and orientation, and then adjust the level to reveal more or less of the content.

Typical use cases include progress indicators, masking effects, and simple reveal animations where a portion of an image or graphic needs to be shown gradually. ClipDrawable implements standard Drawable behavior, including handling bounds changes, opacity, and color filters, and it responds to level changes to update the displayed region accordingly.