How to change the backgroundimage of a button programmaticaly when touching?
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I have an IPhone application in which i am using an IBoutlet button with a background.Now when clicking on that i am calling a webservice and on the success of that i need to change the background of the button.Now i am doing in this way but nothing happening` 

    UIImage *buttonImage = [UIImage imageNamed:@"follow_shop.png"];
    [following setBackgroundImage:buttonImage forState:UIControlStateNormal]; 

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can anybody know how to achieve this?