Question

I make a class level method for Alert:

@interface TestAlert
@end
+ (void)showErrorAlert:(NSTimer *)message
{
.......
 UIAlertView *alert = [[UIAlertView alloc]initWithTitle:nil message:messageIn delegate:self cancelButtonTitle:nil otherButtonTitles:@"OK", nil];
    [alert show];
}

and I want to call it directly in scheduledTimerWithTimeInterval like:

    [NSTimer scheduledTimerWithTimeInterval:0.001 target:TestAlert selector:@selector( showErrorAlert:) userInfo:error repeats:NO];

There have grammar error of course.

I know I can put showErrorAlert to a method:

- (void)showError:(NSTimer *)timer
{
    //NSLog(@"show error %@", error);
    [TestAlert showErrorAlert:(NSString *)[timer userInfo]];
}

Then

[NSTimer scheduledTimerWithTimeInterval:0.001 target:self selector:@selector(showError:) userInfo:error1 repeats:NO];

But it will cause crash when showErrorAlert is called, because error message from showError method has been released.

Can i call showErrorAlert directly, If I can’t, how should I avoid error message’s release ?

Answer 1

Just use [TestAlert class] as a target instead of TestAlert.