如何在Objective-C中创建实例变量

use*_*509 4 objective-c

我有这个例子,我想让my_Picture成为一个实例变量,以便使用removeFromView.有任何想法吗?尝试不同的方法时,我得到了各种各样的警告和错误.先感谢您

- (void) viewDidLoad
{
   UIImageView *my_Picture = [[UIImageView alloc] initWithImage: myImageRef];
   [self.view addSubview:my_Picture];
   [my_Picture release];

   [super viewDidLoad];
}
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And*_*ant 9

要使其成为实例变量,您可以将值存储在类中而不是临时变量中.当您的类被销毁而不是将其添加为子视图后,您也将释放它.

例如

// header file (.h)
@interface MyController : UIViewController
{
  UIImageView* myPicture;
}
@end

// source file (.m)
- (void) viewDidLoad
{
   myPicture = [[UIImageView alloc] initWithImage: myImageRef];
   [self.view addSubview:myPicture];

   [super viewDidLoad];
}

- (void) dealloc
{
   [myPicture release];
   [super dealloc];
}
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