I refer the squareCam example of apple's development library it works fine.
But
When i try to change overlay image on one button click like this
square = [UIImage imageNamed:@"add"];
[self teardownAVCapture];
[self setupAVCapture];
on button click i use this code to change the image and show as overlay.
but i don't know what the problem is but i have to click twice to show the cameraview as first time it just shows black screen.
Help me please. Thanks in advance.