Question

I am learning iOS. I m using Xcode 4.3.2 , and i have created a button, and in the callback, i have used the following code.

1) Created single view application
2) creating a new view -> newV
3) creating a button but;
4) adding but as a subview of newV.
5) adding newV as a subview of main view.

-(IBAction) submitButtonPressed:(id)sender
{
    NSLog (@" Submit Button is pressed ");
    UIView *newV = [[UIView alloc] initWithFrame:[UIScreen mainScreen].bounds];
    newV.backgroundColor = [UIColor colorWithRed:0 green:0 blue:0 alpha:0.5];

    UIButton *but = [[UIButton alloc] init];
    [but setTitle:@"SubView" forState:UIControlStateNormal];
    [newV addSubview:but];
    [self.view addSubview:newV];

}

But the problem i get is, only the view viewV is shown, but button is not shown. How to resolve this issue ?

Answer 1

When you created the button, you didn’t provide a frame. Try using:

UIButton* but = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, buttonWidth, buttonHeight)];

When you created the button, it was of zero size, so you couldn’t see it.