UIButton programatically is not working in iOS - ios

Question

When I click on the UIButton nothing happened
checkbox = [[UIButton alloc] initWithFrame:CGRectMake(73, 324, 15, 15)];
[checkbox setBackgroundImage:[UIImage imageNamed:#"checkbox.png"] forState:UIControlStateNormal];
[checkbox setBackgroundImage:[UIImage imageNamed:#"checkbox-checked.png"] forState:UIControlStateSelected];
[checkbox addTarget:self action:#selector(autologin) forControlEvents:UIControlEventTouchUpInside];
[self.background addSubview:checkbox];

Answer 1

You have to create button like below.
UIButton *checkbox = [UIButton buttonWithType:UIButtonTypeCustom]; // this is important
checkbox.frame = CGRectMake(73, 324, 15, 15)];
[checkbox setBackgroundImage:[UIImage imageNamed:#"checkbox.png"] forState:UIControlStateNormal];
[checkbox setBackgroundImage:[UIImage imageNamed:#"checkbox-checked.png"] forState:UIControlStateSelected];
[checkbox addTarget:self action:#selector(autologin) forControlEvents:UIControlEventTouchUpInside];
[self.background addSubview:checkbox];
You have to create the button first using button property and then give its frame.
If still its not working then self.background addSubview should be self.view addSubview.
What is self.background?

Answer 2

Your code is perfectly fine. You need to check the following .
check whether self.background is placed properly in your view heirarchy, I tried your code with self.view instead of self.background like below and it works perfectly.
self.checkbox = [[UIButton alloc] initWithFrame:CGRectMake(73, 324, 50, 50)];
[self.checkbox setBackgroundImage:[UIImage imageNamed:#"checkbox1.png"] forState:UIControlStateNormal];
[self.checkbox setBackgroundImage:[UIImage imageNamed:#"checkbox2.png"] forState:UIControlStateSelected];
[self.checkbox addTarget:self action:#selector(autologin) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:self.checkbox];
From the error message that you have given
"
Warning: Attempt to present <enter_the_den: 0x7fbf1bd4c4e0> on <ViewController: 0x7fbf1bc771c0> whose view is not in the window hierarchy!
I suspect the issue is in your code inside the method autologin, just comment all the code in your method and just try a log , it should work.
refer this : whose view is not in the window hierarchy

Answer 3

If you read the Apple Documentation for UIButton and look under the heading marked as Creating Button you'll find that the way to create a UIButton is to use buttonWithType: and not initWithFrame:.
Return Value
A newly created button.
Discussion
This method is a convenience constructor for creating button objects with specific configurations. If you subclass UIButton, this method does not return an instance of your subclass. If you want to create an instance of a specific subclass, you must alloc/init the button directly.
When creating a custom button—that is a button with the type UIButtonTypeCustom—the frame of the button is set to (0, 0, 0, 0) initially. Before adding the button to your interface, you should update the frame to a more appropriate value.
The only time when you should use alloc/init with a UIButton is when you have subclassed UIButton however your init method should then implement the buttonWithType: and pass in UIButtonTypeCustom.
So change:
checkbox = [[UIButton alloc] initWithFrame:CGRectMake(73, 324, 15, 15)];
To
// Create a button of type custom
checkbox = [UIButton buttoWithType:UIButtonTypeCustom];
// Now set the frame for your button
[checkbox setFrame:CGRectMake(73, 324, 15, 15)];
// Continue with the rest of your button code
[checkbox setBackgroundImage:[UIImage imageNamed:#"checkbox.png"] forState:UIControlStateNormal];
[checkbox setBackgroundImage:[UIImage imageNamed:#"checkbox-checked.png"] forState:UIControlStateSelected];
[checkbox addTarget:self action:#selector(autologin) forControlEvents:UIControlEventTouchUpInside];
[self.background addSubview:checkbox];

Answer 4

Check userInteractionEnabled property of your background property.
But i see why you have no feedback on button if rest is fine - you use UIControlStateSelected for setting image when button has touch, but you must use UIControlStateHighlighted