iphone - 为什么view2没有出现在此代码中？ (将UIView 2合并到UIView 1中)

为什么view2没有出现在此代码中？结果中，我看到显示的是本地View1标签，顶部带有红色边框，并且在整个绿色边框内，但是看不到view2吗？即不显示带有文本“ View2 Label Text”的标签。

test11ViewController.m

@implementation test11ViewController
- (void)viewDidLoad
{
    [super viewDidLoad];
    View1 *view1 = [[[View1 alloc] initWithFrame:CGRectMake(0.0, 0.0, 400, 100) ] autorelease];
    view1.layer.borderColor = [UIColor redColor].CGColor;
    view1.layer.borderWidth = 1;
    [self.view addSubview:view1];
}
@end

查看1.m

@implementation View1
- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        // Local Label
        CGFloat width = self.frame.size.width;
        UILabel *label = [[[UILabel alloc] initWithFrame:CGRectMake(0.0, 0.0, width, 30)] autorelease];
        label.text = @"View1 Label Text";
        label.layer.borderColor = [UIColor greenColor].CGColor;
        label.layer.borderWidth = 1.0;
        [self addSubview:label];

        // External - Label2
        View2 *view2 = [[[View2 alloc] initWithFrame:CGRectMake(0.0, 30, width, 30)] autorelease];
        [super addSubview:view2];
    }
    return self;
}
@end

View2.m

@implementation View2
- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        CGFloat width = self.frame.size.width;
        UILabel *label = [[[UILabel alloc] initWithFrame:CGRectMake(0.0, 0.0, width, 30)] autorelease];
        label.text = @"View2 Label Text";   // Does  NOT appear in output
        label.layer.borderColor = [UIColor blueColor].CGColor;
        label.layer.borderWidth = 1.0;
    }
    return self;
}
@end

最佳答案

view2并没有真正添加标签。您缺少此：

[self addSubview:label];

换句话说，请尝试：

@implementation View2
- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        CGFloat width = self.frame.size.width;
        UILabel *label = [[[UILabel alloc] initWithFrame:CGRectMake(0.0, 0.0, width, 30)] autorelease];
        label.text = @"View2 Label Text";   // Does  NOT appear in output
        label.layer.borderColor = [UIColor blueColor].CGColor;
        label.layer.borderWidth = 1.0;
        [self addSubview:label];  // NEW LINE HERE
    }
    return self;
}
@end

关于iphone - 为什么view2没有出现在此代码中？ (将UIView 2合并到UIView 1中)，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/5418716/