Question

如果我将此UIImageView设置为IBOutlet，它可以正常工作并显示在SIM卡中。但是以编程方式它不起作用。我想我错过了一步或忘记了一行代码。

声明为

@property (nonatomic,retain) UIImageView  *circleView;

和实施

self.circleView.frame = CGRectMake(0, 0, self.view.frame.size.width,   self.view.frame.size.height);
    self.circleView.center = self.view.center;
    [self.view addSubview:circleView];

Answer 1

您只是忘记初始化UIImageView，这就是为什么它无效......

self.circleView = [[UIImageView alloc] init];
self.circleView.frame = CGRectMake(0, 0, self.view.frame.size.width,   self.view.frame.size.height);
    self.circleView.center = self.view.center;
    [self.view addSubview:circleView];

为什么这个UIImageView不显示？

1 个答案: