I am using a image, and I would like to draw 9 patch for that image. I am not sure in which format i have to save this. Any advice would be much appreciated.
Does this question in stackoverflow help?
Here are the basic rules for creating a 9-patch:
The outer 1px margin can contain only 100% black (RGB 0, 0, 0) or fully transparent.
The black pixels for the top margin and left margin define the stretch points, and must be either a solid line, a single point, or two separate points. If two points are defined, it will stretch equally between the two.
The black pixels for the bottom margin and right margin define the content area. These pixels must be one contiguous line.
When saving, be sure to append the .9.png extension.