Image Stretching Only some Part - ios

Question

I want to image stretching some portion of image. Just below cutout off image. But when text increase it stretch full image. But i want to stretch a image after so.link
balloonView.image =[[UIImage imageNamed:#"chatbg.png"] stretchableImageWithLeftCapWidth:50 topCapHeight:0];;
Please check http://postimg.org/image/7d7lzu9n1/f99d1ebd/

Answer 1

General Discussion : In order to create a stretchable UIImage in iOS like 9Patches in android, you can use this:
UIImage * backgroundImg = [UIImage imageNamed:#"bg.png"];
backgroundImg = [backgroundImg resizableImageWithCapInsets:UIEdgeInsetsMake(2,2, 2, 2)];
[imgView setImage:cellBackgroundImg];
you could also use:
- (UIImage *)stretchableImageWithLeftCapWidth:(NSInteger)leftCapWidth
topCapHeight:(NSInteger)topCapHeight
basically the image is not stretched in the area leftCapWidth pixels from the left and right edge and topCapHeight pixels from the top and the bottom. When the image is scaled the area inside of these limits is subject to stretching.
OP's issue : I think why you are not able to make it work is because your topCapHeight is set to 0. try something like this :
[[UIImage imageNamed:#"chatbg.png"] stretchableImageWithLeftCapWidth:50
topCapHeight:50];

Answer 2

A stretchable image is divided into 9 parts, if both leftCapWidth and topCapHeight are nonzero.
leftCapWidth
<----->
+--------------+ ^
| | | | |
| A | | B | | topCapHeight
|-----+·+------| v
|-----+·+------|
| C | | D |
| | | |
+--------------+
The central parts are always 1 px in size, and this is the part that is stretched, for example:
leftCapWidth (constant!)
<----->
+------------------+ ^
| | | | |
| A | | B | | topCapHeight (constant!)
v |-----+ - - +------| v
| | . . |
| | . . |
^ |-----+ - - +------|
| C | | D |
| | | |
+------------------+
>-----<
stretched region
Just use this code. If you have still any issue for left side arrow, then change the value of LeftCapWidth like 5,10,20 and then check it.
balloonView.image =[[UIImage imageNamed:#"chatbg.png"] stretchableImageWithLeftCapWidth:10 topCapHeight:20];
Hope, this is what you're looking for. Any concern get back to me.