Releasing "referential" variables in method scope
In objective-c (cocoa touch) I have a series of UIViewControllers that I am switching between.
- (void)switchViews:(id)sender
{
UIButton *button = (UIButton *)sender;
UIViewController *nextViewController;
int tag = button.tag;
switch (tag)
{
// -- has already been created
case kFinancialButton:
nextViewController = financials;
break;
case kSocialButton:
if (social == nil)
{
SocialViewController *socialViewController = [[SocialViewContr开发者_StackOverflow社区oller alloc] initWithNibName:@"SocialViewController" bundle:nil];
social = socialViewController;
[socialViewController release];
}
nextViewController = social;
break;
case kTicketingButton:
if (ticketing == nil)
{
TicketingViewController *ticketingViewController = [[TicketingViewController alloc] initWithNibName:@"TicketingViewController" bundle:nil];
ticketing = ticketingViewController;
[ticketingViewController release];
}
nextViewController = ticketing;
break;
}
///////
------> // -- [button/nextViewController release]????
///////
[self setActiveButton:button];
}
As you can see, I'm assigning one of the view controllers to "nextViewController". What I'm wondering is if I need to release this "local" variable or if it's ok to leave alone since it's just pointing to one of my view controllers (which I release in dealloc). I don't think "tag" needs to be released since it's a "primitive", correct? How about button? I don't quite understand what should and shouldn't be released explicitly so perhaps I'm being overcautious. Thanks in advance.
In general you only have to release
a variable that you've retain
'd init
'd or copy
'd.
Edit:
After reading your code a little bit more, it seems like you'd have other issues with bad values. The below code makes a little more sense to me. This assumes that financials, social, and ticketing are all @synthesized
ivars.
- (void)switchViews:(id)sender
{
UIButton *button = (UIButton *)sender;
UIViewController *nextViewController;
int tag = button.tag;
switch (tag)
{
// -- has already been created
case kFinancialButton:
nextViewController = self.financials;
break;
case kSocialButton:
if (!social) {
self.social = [[[SocialViewController alloc] initWithNibName:@"SocialViewController" bundle:nil] autorelease];
}
nextViewController = self.social;
break;
case kTicketingButton:
if (!ticketing) {
self.ticketing = [[[TicketingViewController alloc] initWithNibName:@"TicketingViewController" bundle:nil] autorelease];
}
nextViewController = self.ticketing;
break;
}
// Do something with nextViewController I'd assume
[self setActiveButton:button];
}
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