[Graphic] Vector Drawables

Drawable 分為兩類:


Bitmap Drawables

• Bitmap files, ex:
• PNG which are rendered as images by the OS.
• 9-patch bitmaps which enable the OS to anamorphically distort the image to fit a particular region.

Vector Drawables

• Consist of XML files which contain some basic vector drawing command which the OS renders dynamically at runtime.
• 缺點:
• Require more processing power to render,particularly gradients; 
• The drawing primitives are not as flexible as those in your favorite image manipulation software.

兩種差異是單一的 vector drawable 在不同顯示規格下的縮放表現較好(a single vector drawable will scale much better on a variety of different display types)。


* Reference
- Vector Drawables – part 1