Question

当我使用此方法(void)longpressed:(UILongPressGestureRecognizer *)时，长按手势对我不起作用。当我长按标签时，不会调用手势。

 - (void)viewDidLoad {
    [super viewDidLoad];
    array =[NSMutableArray arrayWithObjects:@"hello",@"we",@"Are",@"Swift", nil];
    int ypoint = 60;
    for (int i=0; i<[array count]; i++) {
        label=[[UILabel alloc]initWithFrame:CGRectMake(100, ypoint, 300, 200)];
        label.backgroundColor =[UIColor clearColor];
        label.text =[array objectAtIndex:i];
        [label setTag:i];
        [self.view addSubview:label];
        ypoint = ypoint +70;
    }
    [label setUserInteractionEnabled:YES];
    longPressGesture =[[UILongPressGestureRecognizer alloc]initWithTarget:self action:@selector(longpressed:)];
    longPressGesture.minimumPressDuration = 0.6;
    longPressGesture.delegate = self;
    [label addGestureRecognizer:longPressGesture];
    // Do any additional setup after loading the view, typically from a nib.
}

-(void)longpressed:(UILongPressGestureRecognizer *)gesture{
     if (gesture.state == UIGestureRecognizerStateBegan) {
            UILabel *myLabel= (UILabel *)gesture.view ;
            NSInteger myLabelTag =[myLabel tag];
            NSString *nameString=[array objectAtIndex:myLabelTag];
            NSLog(@"%@",nameString);                
     }
}

- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer  {
    return YES;
}

Answer 1

将userInteractionEnabled = true属性设置为您的标签。

Answer 2

尝试这个，因为长按被识别，

-(void)longpressed:(UILongPressGestureRecognizer *)gesture
  {
    if (gestureRecognizer.state != UIGestureRecognizerStateEnded) 
       {
        return;
        }  
                      //UILabel *myLabel= (UILabel *)gesture.view ;
                      NSInteger myLabelTag =[label tag];
                      NSString *nameString=[array objectAtIndex:myLabelTag];
                      NSLog(@"%@",nameString);                

  }

Answer 3

试试这个

array =[NSMutableArray arrayWithObjects:@"hello",@"we",@"Are",@"Swift", nil];
longPressGesture =[[UILongPressGestureRecognizer alloc]initWithTarget:self action:@selector(longpressed:)];
longPressGesture.minimumPressDuration = 0.6;
longPressGesture.delegate = self;

int ypoint =60;
for (int i=0 ;i<[array count]; i++)
{
    label=[[UILabel alloc]initWithFrame:CGRectMake(100, ypoint, 300, 200)];
    label.backgroundColor =[UIColor clearColor];
    label.text =[array objectAtIndex:i];
    [label setTag:i];
    [self.view addSubview:label];
    label.backgroundColor  = [UIColor redColor];
    [label setUserInteractionEnabled:YES];
    [label addGestureRecognizer:longPressGesture];

    ypoint   = ypoint +70;
}

在您的代码中进行更改后，它可以正常工作

Answer 4

我尝试了我的Xcode，我发现了

label=[[UILabel alloc]initWithFrame:CGRectMake(100, ypoint, 300, 200)]; 你的定义有一些问题，在这里你应该定义一个新标签，而不是使用全局变量。改为这个

UILabel *newLabel=[[UILabel alloc]initWithFrame:CGRectMake(100, ypoint, 300, 200)];

Answer 5

根据您上次的评论，当您点击标签时，标签会出错。

这是因为您为所有标签使用了全局对象UILongPressGestureRecognizer识别器。

您需要为所有标签添加单独的手势识别器，这些标签对于每个标签都是唯一的。

因此，在创建标签时创建本地手势识别器，因此您的代码现在将是：

for (int i=0; i<[array count]; i++) 
{
    // Label creation code...

    UILongPressGestureRecognizer *longPressGesture =[[UILongPressGestureRecognizer alloc]initWithTarget:self action:@selector(longpressed:)];
   // gesture settings...

   // Add UILongPressGestureRecognizer for each label.
   [label addGestureRecognizer:longPressGesture]
}

Answer 6

为什么要在其上添加标签。只有最后一个手势识别方法才能被注册。尝试点击视图的底部。将颜色更改为红色，然后按住它将起作用的底部区域。

label.backgroundColor =[UIColor redColor];

如果要将手势识别添加到所有标签，请将其放在for循环中。但是你为什么要使用标签，而是使用按钮来避免复杂化。

长按手势不工作

6 个答案: