Question

我有以下代码添加一个UIView，然后添加一个UIImageView和UILabel，UIView显示正确，但我放在视图中的任何内容都没有显示。我到处都看，但我找不到答案。 UIView是在某些条件下呈现的，当它被点击时它会消失。

这是我的代码。

UIView *actionView = [[UIView alloc] initWithFrame:CGRectMake(20, 180, 280, 165)];
        UITapGestureRecognizer *singleFingerTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleSingleTap:)];
        [actionView addGestureRecognizer:singleFingerTap];
        actionView.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:0.5f];
        actionView.layer.cornerRadius = 5;
        actionView.layer.masksToBounds = YES;
        [self.view addSubview:actionView];
        UILabel *actionText = [[UILabel alloc] initWithFrame:CGRectMake(20, 180, 280, 165)];
        actionText.text = @"Hello";
        actionText.textColor = [UIColor redColor];
        actionText.textAlignment = NSTextAlignmentCenter;
        [actionText setTextColor:[UIColor redColor]];
        [actionText setBackgroundColor:[UIColor clearColor]];
        [actionText setFont:[UIFont fontWithName: @"Trebuchet MS" size: 14.0f]];
        actionText.Frame = CGRectMake(20, 180, 280, 165);
         [actionView addSubview:actionText];
        UIImage* image = [UIImage imageNamed:[NSString stringWithFormat:@"trash-icon.png"]];
        UIImageView* blockView = [[UIImageView alloc] initWithImage:image];
        blockView.frame = CGRectMake(109, 273, 40, 40);
      [actionView addSubview:blockView];

Answer 1

更改框架位置，例如..

    UILabel *actionText = [[UILabel alloc] initWithFrame:CGRectMake(20, 10, 280, 40)];
    actionText.text = @"Hello";
    actionText.textColor = [UIColor redColor];
    actionText.textAlignment = NSTextAlignmentCenter;
    [actionText setTextColor:[UIColor redColor]];
    [actionText setBackgroundColor:[UIColor clearColor]];
    [actionText setFont:[UIFont fontWithName: @"Trebuchet MS" size: 14.0f]];
    [actionView addSubview:actionText];

    UIImage* image = [UIImage imageNamed:[NSString stringWithFormat:@"trash-icon.png"]];
    UIImageView* blockView = [[UIImageView alloc] initWithImage:image];
    blockView.frame = CGRectMake(109,70, 40, 40);
    [actionView addSubview:blockView];

Answer 2

设置视图的框架时，重要的是要记住原点与添加到它的超视图的坐标系有关。

因此，当您将标签的框架设置为：

时

UILabel *actionText = [[UILabel alloc] initWithFrame:CGRectMake(20, 180, 280, 165)];

x = 20的原点，y = 180最终成为actionView的原点。现在这是你的问题，因为你的actionView只有165px高，你告诉actionText subView它的y origin是180，它远远超出了actionView的底部。

对于你的actionText，你应该按如下方式分配它：

UILabel *actionText = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 280, 165)];

和你的blockView，如：

blockView.frame = CGRectMake(89,93, 40, 40);

为什么我的UIView中没有显示任何内容？

2 个答案: