为什么 UITapGestureRecognizer 在 keyWindow 的子视图（全屏）中不起作用？

Question

我在这里问过 (UIView added as an UIWindow subview doesn't respond to taps)，但我认为它应该有自己的问题。

如果我以这种方式设置子类 UIView (CustomView)，我无法让手势在视图中工作：

CustomView *customView = [[[CustomView alloc] initWithFrame:[UIApplication sharedApplication].keyWindow.frame];

customView.frame = [UIApplication sharedApplication].keyWindow.bounds; // leaves space at bottom of screen if not here

[[UIApplication sharedApplication].keyWindow addSubview:customView];

但如果我这样设置，手势可以正常工作：

CustomView *customView = [[[CustomView alloc] initWithFrame:[UIApplication sharedApplication].keyWindow.frame];

customView.frame = [UIApplication sharedApplication].keyWindow.bounds; // leaves space at bottom of screen if not here

[[UIApplication sharedApplication].windows[0] addSubview:customView];

请注意，使用 .windows[0] 而不是 .keyWindow 意味着状态栏仍然存在，所以当我取消隐藏 customView 以获得空的全屏时，我必须隐藏它。

在自定义视图中：

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];

    id mainView;
    if (self)
    {
        NSArray *subviewArray = [[NSBundle mainBundle] loadNibNamed:@"CustomNib" owner:self options:nil];
        mainView = [subviewArray objectAtIndex:0];
    }
    return mainView;
}

这是手势设置，也在 customView 中：

UITapGestureRecognizer *singleFingerTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleTap:)];
[self addGestureRecognizer:singleFingerTap];

任何想法为什么手势识别器在视图是 .keyWindow 的子视图时不起作用但在视图是 .windows[0] 的子视图时起作用？

Answer 1

在initWithFrame 中，您返回的是UIView --- 不是 CustomView 的实例。

您可能希望您的CustomView 代码如下所示：

#import "CustomView.h"

@implementation CustomView

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];

    UIView *mainView;
    if (self)
    {
        NSArray *subviewArray = [[NSBundle mainBundle] loadNibNamed:@"CustomNib" owner:self options:nil];
        mainView = [subviewArray objectAtIndex:0];
        mainView.frame = self.bounds;
        mainView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
        [self addSubview:mainView];
        [self setupTap];
    }
    return self;
}

- (void) setupTap {

    UITapGestureRecognizer *singleFingerTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleTap:)];
    [self addGestureRecognizer:singleFingerTap];

}

- (void)handleTap:(UIGestureRecognizer *)g {
    NSLog(@"Tap in CustomView!");
}

@end