1

I have a method in which I alloc and init an 

UIView (`tabsClippedView = [[[UIView alloc] initWithFrame:tabsClippedFrame] autorelease];`).

This view has another view added to it 

(`tabsView = [[[UIView alloc] initWithFrame:tabsFrame] autorelease];`).

Then I initiate a couple of buttons

(e.g. `UIButton* btn = [[[UIButton alloc] initWithFrame:frame] autorelease];`)

and add them to the subview of the view.

Now from time to time, I need to delete all the buttons and assign them again. Is the best way to delete the entire view or simply the subview to which I added the buttons?

How would I need to do this (without memory leaking etc.)? Would a simple

self.tabsView = nil;

suffice to delete the view and all of its subviews (i.e. the buttons)?

Or would it better to delete the superview as well, to start entirely from scratch:

self.tabsClippedView = nil;
Spring
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n.evermind
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  • I found the answer to this in another stackoverflow question: http://stackoverflow.com/a/2156046/374873 – apb Jan 05 '13 at 14:52

2 Answers2

14

Since your UIView is autoreleased, you just need to remove it from the superview. For which there is the removeFromSuperview method.

So, you'd just want to call [self.tabsView removeFromSuperview]. As long as your property declaration is set to retain that's all you'll need.

lxt
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  • Thanks... so what about the self.tabsView = nil; command -- would that be wrong or different from removeFromSuperview? Thanks for your help! – n.evermind May 01 '11 at 20:56
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    `self.tabsView = nil` won't remove it from the superView. – cweinberger May 01 '11 at 21:05
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    What s/he said - you don't need to set it to nil, because as long as you've set up your @property declaration correctly this will be taken care of when you reassign the property. – lxt May 01 '11 at 21:30
4

Another solution: don't remove your UIButtons but re-use them. Don't know the exact use-case for you, but you may assign tags to your UIButtons and find them with [UIView viewWithTag:].

UIButton* btn = [[UIButton alloc] initWithFrame:frame];
btn.tag = 42; // some unique identifier for the button.. dont use 0 (zero)
[tabsView addSubview:btn];
[btn release];

later...

UIButton* btn = (UIButton*)[tabsView viewWithTag:42];
if(btn && [btn isKindOfClass:[UIButton class]]) {
    // do some stuff with btn
}

Besides: In my opinion you only should use autorelease when you've no other options. Here it's easy for you to release btn after adding it as subview.

cweinberger
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  • Thanks, but I need to entirely remove some buttons, so I guess this won't work. Thanks for your thoughts, though. – n.evermind May 01 '11 at 20:56