selector - 如何在 UIGestureRecognizer initWithTarget 动作中将参数传递给动作

Question

我正在使用下面的代码

UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(processTap)];

- (void) processTap
{
//do something
}

但我需要向 processTap 函数发送数据。有没有办法做到这一点？

Answer 1

例子：

UIImageView *myPhoto = [[UIImageView alloc] initWithImage: [UIImage imageNamed:@"tab-me-plese.png"]];
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(processTap:)];

[myPhoto setTag:1]; //set tag value
[myPhoto addGestureRecognizer:tap];
[myPhoto setUserInteractionEnabled:YES];

- (void)processTap:(UIGestureRecognizer *)sender
{
    NSLog(@"tabbed!!");
    NSLog(@"%d", sender.view.tag);    
}

Answer 2

在iOS - UITapGestureRecognizer - Selector with Arguments有一个类似问题的很好的答案，但是如果你想传递你不想附加到视图的数据，我建议创建第二个函数来访问你需要的数据. 例如：

UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(passDataToProcessTap)];

- (void)passDataToProcessTap {
    [self processTapWithArgument:self.infoToPass];
    // Another option is to use a static variable,
    // Or if it's not dynamic data, you can just hard code it
}

- (void) processTapWithArgument:(id)argument {
    //do something
}