ios - UITap 手势仅适用于一种 View

Question

我在 View Controller 中有以下代码:

@interface QuizController ()

@property (weak, nonatomic) IBOutlet UITextView *questionText;
@property (weak, nonatomic) IBOutlet UITextView *one;
@property (weak, nonatomic) IBOutlet UITextView *two;
@property (weak, nonatomic) IBOutlet UITextView *three;
@property (weak, nonatomic) IBOutlet UITextView *four;

@property(strong, nonatomic) NSMutableArray* possAnswers;
@end

@implementation QuizController

- (void)viewDidLoad {
   [super viewDidLoad];
   [self.manager setupGame];
   self.possAnswers = [[NSMutableArray alloc] initWithObjects:@"a", @"b", @"c", @"d", nil];

}

//This listens for a tap on any of the TextViews and sets the background to Blue 

- (IBAction)fourTapped:(id)sender {
    NSLog(@"There's been a tap!");
    [self blankBoxes];

    if( [sender isKindOfClass:[UITapGestureRecognizer class]] )
    {

        UITapGestureRecognizer* tgr = (UITapGestureRecognizer*)sender;
        UIView* view = tgr.view;
        if( [view isKindOfClass:[UITextView class]]){
            UITextView* tv = (UITextView*)view;
            NSLog([tv text]);
            [tv setBackgroundColor:[UIColor blueColor]];
        }

    }

}

-(void)blankBoxes
{
  [_one setBackgroundColor:[UIColor whiteColor]];
  [_two setBackgroundColor:[UIColor whiteColor]];
  [_three setBackgroundColor:[UIColor whiteColor]];
  [_four setBackgroundColor:[UIColor whiteColor]];
}

但是，无论点击哪个 View ，唯一突出显示的 UITextView 是 _one。我不明白这是为什么。如果有人能向我指出这一点，我将不胜感激。

Answer 1

手势识别器仅附加到一个 View 。这是设计使然。如果您想要一个单一的手势识别器来识别多个 View 上的点击，您必须将它附加到一个公共(public)的、封闭的 super View ，然后查看点击坐标并找出哪个 View 被点击。

通常，您只需为需要响应点击的每个 View 创建不同的手势识别器。