objective-c - 从另一个类添加和控制 UIImageView subview

Question

我有两个类:MainViewController 和 PlayerImageController (NSObject)

我如何才能将我的 UIImageView 的 subview 从 PlayerImageController 添加到我的 MainViewController 并指示像这样的操作

- (void)viewDidLoad
{
    [super viewDidLoad];
    [self.view addSubview:[PlayerImageController addPlayerImage]];
}

- (void)somethingHappened
{
    [PlayerImageController changePlayerImage];
}

并在我的 PlayerImageController 类中使用我的方法

+ (UIImageView *) addPlayerImage
{
    heroPlayerImageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"hero-still.png"]];
    [heroPlayerImageView setFrame:CGRectMake(151, 200, 17, 23)];
    return heroPlayerImageView;
}

+ (void) changePlayerImage 
{
  //change image
}

谢谢!

Answer 1

我认为在你的情况下你应该使用委托(delegate)模式。声明:

@protocol PlayerImageUpdater
  - createPlayerImage;
  - changePlayerImage;
@end

然后添加:

@interface PlayerImageController <PlayerImageUpdater>

然后添加到 MainViewController ivar 和属性，如:

@property (...) id<PlayerImageUpdater> playerDelegate;

将此委托(delegate)设置为:mainViewController.playerDelegate = playerImageControllerInstance;

并在代码中使用:

[playerDelegate createPlayerImage];
[playerDelegate changePlayerImage];