Question

I dynamically add a subview to another uiview;

in the subview ,click a button to go back by the following method:

[self removeFromSuperView ];

but after manny times added subview and removed it,my app could crash ,the log said it was killed .

I found that calling [self removeFromSuperView] didn’t release self. So what’s the best methods to releas it?

Answer 1

If you are retaining the UIView on creation (or adding it to an array) the retain count will increase. For example:

// Retain count is 1
UIView *myView = [[UIView alloc] initWithFrame:myFrame];

// Retain count is 2
[myParentView addSubview:myView];

// Retain count is 1 again
[myView removeFromSuperView];

In the above example you can autorelease the view if it is immediately added as a subView or release it in your dealloc if it is an iVar.

EDIT: (other reasons your view could be retained)

// Retain count +1
[myArray addObject:myView];

// Retained in the setter created by the @synthesize directive
@property(nonatomic, retain) UIView *myView;

Anything else that states in the documentation that the property is retained.

You should also be careful of creating objects in the loadView method of a VC, if you do make sure you release them, as they will be created again when the loadView is called. This will happen if you VC’s view is unloaded and then reloaded.