Can't see the button - objective-c

Question

- (void)viewDidLoad{
int leftBorder = 80;
int topBorder = 160;
int width = 150;
int height = 50;
UIView *myView = [[UIView alloc] initWithFrame:CGRectMake(leftBorder, topBorder, width, height)];
myView.layer.cornerRadius = 5;
myView.backgroundColor = [UIColor redColor];
[self.view addSubview:myView];
UIButton *testButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
testButton.frame = CGRectMake(0, 0, 50, 50);
[testButton setTitle:#"testButton" forState:UIControlStateNormal];
[testButton addTarget:self action:#selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside];
[self.myView addSubview:self.testButton];
self.myView.hidden = YES;
[super viewDidLoad];
}
Hi, sorry for stupid question! I'm newby in xcode. Why I didn't see this button? And How can I hide button after click? I need button inside the frame.

Answer 1

Simple remove self.myView.hidden = YES;
To add you click listener, two solution:
By code in your viewDidLoad:
- (void)viewDidLoad {
[super viewDidLoad];
[mybutton addTarget:self action:#selector(myButtonClick:) forControlEvents:(UIControlEvents)UIControlEventTouchDown];
}
- (void)myButtonClick:(id)sender {
myButton.hidden = YES;
}
Or via interface Builder (preferred), The easiest way is to actually define the handler/action in Xcode using the IBAction declaration in the interface file (add the declaration just before the #end statement). Then attach the action to the button

Answer 2

you are adding self.testButton instead of the created testButton.
[self.myView addSubview:testButton];
you did not assign myView to your property.
[self.view addSubview:myView]; self.myView = myView;
remove self.myView.hidden = YES;
Another remark:
You should usually call super as early as possible. Otherwise, the superclass may interfere with your own implementation.

Answer 3

There are several issues in your code.
You add testButton as subview to self.myView. Then you hide self.myView. As a result neither self.myview nor its subviews will be visible.
You get confused with your local varialbles and instance varialbes. Apparently there is an instance variable and property myView. Otherwise you coudn't use self.myView. And you declare a local variable myView, which is not the same as the instance variable. This may well be perfectly ok. But I got a guts feeling that you did this not intentionally. Your self.myView may well be nil at the point in time where you add the subview. And even the subview self.testButton may be nil. That will compile file and execute fine but nothing does happen actually.
The same for testButton.
I suggest to change the code a bit, assuming there are properties for myView and testButton of the appropriate types:
self.myView = [[UIView alloc] initWithFrame:CGRectMake(leftBorder, topBorder, width, height)];
self.myView.layer.cornerRadius = 5;
self.myView.backgroundColor = [UIColor redColor];
[self.view addSubview:self.myView];
self.testButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
self.testButton.frame = CGRectMake(0, 0, 50, 50);
[self.testButton setTitle:#"testButton" forState:UIControlStateNormal];
[self.testButton addTarget:self action:#selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside];
[self.myView addSubview:self.testButton];
self.myView.hidden = NO;