objective-c - UIButton 触摸后保留计数器增加

Question

我创建了一组相同的自定义类型的对象。所有对象都有方法 showDeleteButton 和 hideDeleteButton。我发现当我隐藏删除按钮(删除它)时，按下的按钮具有 retainCounter == 2。

这里是代码:

-(void)showDeleteButton {
if(!isDeleteButtonLoaded) { // Check that method was't triggered twice
    UIButton *aDeleteButton = [[UIButton alloc] initWithFrame:CGRectMake(-3, -7, 30, 29)]; // RC == 1
    [aDeleteButton setImage:[UIImage imageNamed:@"close_button.png"] forState:UIControlStateNormal];
    [self addSubview:aDeleteButton]; // RC == 2
    [aDeleteButton addTarget:self action:@selector(deleteButtonPressed:) forControlEvents:UIControlEventTouchUpInside];
    deleteButton = aDeleteButton;
    [aDeleteButton release]; // RC == 1
    isDeleteButtonLoaded = YES;
    NSLog(@"delete button retain count (created): %d", [deleteButton retainCount]);
    [self setNeedsDisplay];
}

-(void)deleteButtonPressed:(id)sender {
[delegate deleteImageAtPath:self.imageFullPath];

-(void)hideDeleteButton {
if(isDeleteButtonLoaded) {
    NSLog(@"delete button retain count (before): %d", [deleteButton retainCount]); // RC == 1
    [deleteButton removeFromSuperview]; // RC == 0
    deleteButton = nil;
    isDeleteButtonLoaded = NO;
    [self setNeedsDisplay];
}

所以对于按下的按钮 NSLog 在第二种方法中显示 RC == 2!有任何想法吗？我 100% 确定无法从类外访问 deleteButton。

Answer 1

不要看 RETAINCOUNT

咳咳

对于任何理智的人来说，retainCount 是没有意义的，只要您遵循内存规则，一切都会好起来的。