Question

I am trying to call a new view inside my existing view

TransactionFinish *childView= [[TransactionFinish alloc] initWithNibName:@"TransactionFinish" bundle:nil];

        childView.view.frame = self.view.frame;

        childView.view.frame=CGRectMake(10, 10, self.view.frame.size.width-20, self.view.frame.size.height-20);
        childView.view.alpha = 0.0f;
        [self.view addSubview:childView.view];

        [UIView animateWithDuration:0.5 delay:0.0 options:UIViewAnimationCurveEaseOut
                         animations:^{
                             childView.view.alpha = 1.0f;
                         }
                         completion:^(BOOL finished) {
                         }];

It is going inside ViewDidLoad() of TransactionFinish(I have tried debugging it) but it gives me Thread EXEC_BAD_ACCESS(code=1,address=0x31f54e62) with green color

Answer 1

The issue lays with the lifetime of childView. You instantiate and store a reference to it into a local variable:

TransactionFinish *childView= [[TransactionFinish alloc] initWithNibName:@"TransactionFinish" bundle:nil];

If you are using ARC, when the local variable goes out of scope, the object referenced by it (childView) is deallocated.

If you are not using ARC, I suppose you are doing:

[childView release];

somewhere to avoid childView to be leaked (as the code you pasted above would imply).

Either hypothesis would explain why you get the crash: when viewDidLoad is called, the controller has already been deallocated.

Adding childView view to self.view:

    [self.view addSubview:childView.view];

will retain childView.view but not childView. So the controller is deallocated, while its view is not.

A fix to this is creating a strong property in your class to store a reference to your childView controller:

@property(nonatomic, strong) TransactionFinish *childView;

Another possibility is using controller containment; you could do something li

[vc willMoveToParentViewController:self];
[self addChildViewController:childView];
[self.view addSubview:childView.view]; // or something like this.
[childView didMoveToParentViewController:self];

but this will only work on iOS5+.