Creating UIButtons Programmatically - unrecognized selector sent to instance - ios

Question

Relevant code:
- (void) createButtons {
NSMutableArray *buttonTitleArray = [[NSMutableArray alloc] init];
[buttonTitleArray addObject:#"Website"];
[buttonTitleArray addObject:#"Blah"];
[buttonTitleArray addObject:#"Blah"];
int xPosition = 20;
for (int i = 0; i <= buttonTitleArray.count-1; i++) {
UIButton *button = [[UIButton alloc] initWithFrame:CGRectMake(xPosition, 25, 90, 40)];
button.userInteractionEnabled = TRUE;
[button setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
[button setTitle:[buttonTitleArray objectAtIndex:i] forState:UIControlStateNormal];
button.backgroundColor = [UIColor colorWithRed:1 green:200.0/255.0 blue:0 alpha:1];
button.titleLabel.font = [UIFont systemFontOfSize:17];
[self.buttonArray addObject:button];
xPosition += 91;
}
for (UIButton *button in self.buttonArray) {
[button addTarget:self action:#selector(showWebsite:) forControlEvents:UIControlEventTouchDown];
[self.view addSubview:button];
}
}
- (void)showWebsite:(UIButton *)sender {
NSLog(#"Website");
}
In init:
NSMutableArray *tempArray = [[NSMutableArray alloc] init];
self.buttonArray = tempArray;
For testing purposes I made all the buttons have the same target.
When I click the button, I get unrecognized selector sent to instance.
Any thoughts here?

Answer 1

For some reason your self in your posted code gets released and the pointer location gets re-used by the OS as a UIGestureDelayedTouch.
Make sure the object that you are creating these buttons in does not get released by the OS before you want to use the showWebsite function.
Sometimes people use code like:
-(void)function
{
UIViewController *controller = [[UIViewController alloc] init];
[someOtherView addSubview:controller.view];
}
In this case at the end of the function the controller gets released (as there are no further references to it) and anything that could point to it in the future will point to an invalid (deallocated and possibly re-used) object.
UIButton does not retain objects set as targets, so the OS thinks the objects are valid for release if they are not retained by anything else in the program.