Question

- (IBAction)start:(UIButton *)sender {
  NSString *t=@"123";   // line 1
  self.detailDescriptionLabel.text=t;
}

The syntax check is correct, but when I build and run it on iphone, it breaks out at line 1 and sending the error message like “variable is not a CFString”

How to solve this problem?

And it is working when I wrote this:

- (IBAction)start:(UIButton *)sender {
  self.detailDescriptionLabel.text=nil;
}

I really think the problem lies in how to correctly assign a string constant to a UILabel’s text property.

Answer 1

Ok, it is stupid… I wrongly pressed the shotcut key and a breakpoint to it…..So actually there is no mistakes in the code, just my mistake in the XCode IDE.