Resizing a button in iOS programmatically - ios

Question

I am using XCode 4.6.1 and developing for iOS 6.
I have added a button to the storyboard. I have created an outlet in my implementation file ViewController.m:
//
// ViewController.m
//
#import "ViewController.h"
#interface ViewController ()
#property (weak, nonatomic) IBOutlet UIButton *b1;
#end
I try to change the button b1's properties as follows (in this same file: ViewController.m):
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
self.b1.alpha = 0.5;
self.b1.frame = CGRectMake(0,0,123,412);
}
When I run the app in the simulator, the alpha of the button is successfully set to 0.5.
However, the position and size of the button doesn't change.
I have tried various ways to make it happen. However nothing seems to work. I would like to know what am I doing wrong. I am pretty new to Objective C. Any help would be greatly appreciated.

Answer 1

You are probably using autolayout:
When using autolayout you cannot manually change your outlets frames. You have two options: you can either disable autolayout (then your code should work), or create outlets to your constraints and then modify the constrains programmatically:
#property (weak, nonatomic) IBOutlet NSLayoutConstraint *widthConstraint;
and then in your code:
self.widthConstraint.constant = 123;
and so on with all the constraints that need to be modified.