Question

I am using a Nib as a template for several buttons. It seemed to work fine, they each have their own independent state. However when I went to release the buttons I would crash in the dealloc. Here is the code…

mSoundBtns = new cSoundButton*[mNumSounds];
for(unsigned int i = 0 ; i < mNumSounds; ++i) {
    mSoundBtns[i] = nil;
}

for(unsigned int s = 0; s < mNumSounds; ++s) {

    [[NSBundle mainBundle] loadNibNamed:@"InstanceSoundButton" owner:self options:nil];
    //Auto Loads via Outlet into 'soundNib'

    mSoundBtns[s] = soundNib;
    soundNib = nil;

    uint32 count = mSoundBtns[s].retainCount;
    NSLog(@"Last Count: %d", count);
}


for(unsigned int j = 0; j < mNumSounds; ++j) {
    [mSoundBtns[j] release];  //**** Crash here on 7th (of 8) release
    mSoundBtns[j] = nil;
}

Header:

@interface cLocationContext {
   ...

   cSoundButton** mSoundBtns;
   IBOutlet cSoundButton* soundNib;

}

@property (nonatomic, assign) IBOutlet cSoundButton* soundNib;

@end

The Nib is very simple, it just include a parent view and a child view of a custom view type.

cSoundButton simply keeps track of a name and a boolean state Mute or Not. Here is the dealloc

- (void)dealloc {

    delete[] mSoundTag;

    // Call the inherited implementation
    [super dealloc];  //****Crashes in here
}

The crash is inside the call to super dealloc, in UIButton -> UIButtonContent dealloc. I assume I am doing something poor with my memory management like deallocing twice but I can’t spot where.

Is what I am doing by loading the nib multiple times legal?

Answer 1

You have to retain the button as soon as you load it from the NIB. If you don’t, you are not allowed to release it later, and you won’t be able to access the button once your code returns control to the runloop (when the autorelease pool is drained).

PS: Wouldn’t it be easier to use a Cocoa collection (NSMutableArray) to store the references to the buttons? Your code looks too complicated to me.