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iOS

Posted by Paul Searle
Paul Searle
3,645 Points

button flip help

So I'm trying to make a green button flip over to a red button, then back. 

- (IBAction)touchCardButton:(UIButton *)sender
{
    if ([sender.currentBackgroundImage isEqual:@"buttonImageGreen"]) {
        [sender setBackgroundImage:[UIImage imageNamed:@"buttonImageRed"]
                          forState:UIControlStateNormal];
        [sender setTitle:@"duh" forState:UIControlStateNormal];
    }
    else {
        [sender setBackgroundImage:[UIImage imageNamed:@"buttonImageGreen"]
                          forState:UIControlStateNormal];
        [sender setTitle:@"1" forState:UIControlStateNormal];
    }
}

Right now it's not flipping over. I'm pretty sure the problem is with the "isEqual:" method, but I'm not sure what the right syntax is to say "if the button background is green, then make it red.

Any help is much appreciated. Thanks.

2 Answers

Stone Preston
Stone Preston
42,016 Points

hmm maybe try 

if ([sender.currentBackgroundImage isEqual:[UIImage imageNamed:@"buttonImageGreen.png"]])

Im pretty sure you have to include the extension to compare two images. you could also try comparing the titles of the button if you have two different titles depending on if its green or red using something like

if ([sender.title isEqualToString:@"someTitle"])

its probably easier to set a bool property and use that for comparison of state instead of images/titles

edit: looking over the answers posted here, image comparison is not the way you want to go. As I suggested you should probably find another way of comparing your buttons state using either a bool or possibly the title of the button etc

Paul Searle
Paul Searle
3,645 Points

Thanks Stone.

The first one didn't work, but I think you're right about the second option. Will give that a try.

Paul Searle
Paul Searle
3,645 Points
Paul Searle
Paul Searle
3,645 Points

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