difference between frame and bounds Property

bounds
The bounds rectangle, which describes the view’s location and size in its own coordinate system.

@property(nonatomic) CGRect bounds
Discussion
On the screen, the bounds rectangle represents the same visible portion of the view as its frame rectangle. By default, the origin of the bounds rectangle is set to (0, 0) but you can change this value to display different portions of the view. The size of the bounds rectangle is coupled to the size of the frame rectangle, so that changes to one affect the other. Changing the bounds size grows or shrinks the view relative to its center point. The coordinates of the bounds rectangle are always specified in points.

Changing the frame rectangle automatically redisplays the receiver without invoking the drawRect: method. If you want the drawRect: method invoked when the frame rectangle changes, set the contentMode property to UIViewContentModeRedraw.

Changes to this property can be animated.

The default bounds origin is (0,0) and the size is the same as the frame rectangle’s size.



frame
The frame rectangle, which describes the view’s location and size in its superview’s coordinate system.

@property(nonatomic) CGRect frame
Discussion
This rectangle defines the size and position of the view in its superview’s coordinate system. You use this rectangle during layout operations to size and position the view. Setting this property changes the point specified by the center property and the size in the bounds rectangle accordingly. The coordinates of the frame rectangle are always specified in points.

Warning If the transform property is not the identity transform, the value of this property is undefined and therefore should be ignored.
Changing the frame rectangle automatically redisplays the receiver without invoking the drawRect: method. If you want the drawRect: method invoked when the frame rectangle changes, set the contentMode property to UIViewContentModeRedraw.

Changes to this property can be animated. However, if the transform property contains a non-identity transform, the value of the frame property is undefined and should not be modified. In that case, you can reposition the view using the center property and adjust the size using the bounds property instead.