我如何添加一个触摸事件到一个UIView? 我试一试:
UIView *headerView = [[[UIView alloc] initWithFrame:CGRectMake(0, 0, tableView.bounds.size.width, nextY)] autorelease];
[headerView addTarget:self action:@selector(myEvent:) forControlEvents:UIControlEventTouchDown];
// ERROR MESSAGE: UIView may not respond to '-addTarget:action:forControlEvents:'
我不想创建一个子类然后重写
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
当前回答
以下是Swift版本:
// MARK: Gesture Extensions
extension UIView {
func addTapGesture(#tapNumber: Int, target: AnyObject, action: Selector) {
let tap = UITapGestureRecognizer (target: target, action: action)
tap.numberOfTapsRequired = tapNumber
addGestureRecognizer(tap)
userInteractionEnabled = true
}
func addTapGesture(#tapNumber: Int, action: ((UITapGestureRecognizer)->())?) {
let tap = BlockTap (tapCount: tapNumber, fingerCount: 1, action: action)
addGestureRecognizer(tap)
userInteractionEnabled = true
}
}
其他回答
基于已接受的答案，你可以定义一个宏:
#define handle_tap(view, delegate, selector) do {\
view.userInteractionEnabled = YES;\
[view addGestureRecognizer: [[UITapGestureRecognizer alloc] initWithTarget:delegate action:selector]];\
} while(0)
这个宏使用ARC，所以没有发布调用。
宏使用示例:
handle_tap(userpic, self, @selector(onTapUserpic:));
简单实用的扩展:
extension UIView {
private struct OnClickHolder {
static var _closure:()->() = {}
}
private var onClickClosure: () -> () {
get { return OnClickHolder._closure }
set { OnClickHolder._closure = newValue }
}
func onTap(closure: @escaping ()->()) {
self.onClickClosure = closure
isUserInteractionEnabled = true
let tap = UITapGestureRecognizer(target: self, action: #selector(onClickAction))
addGestureRecognizer(tap)
}
@objc private func onClickAction() {
onClickClosure()
}
}
用法:
override func viewDidLoad() {
super.viewDidLoad()
let view = UIView(frame: .init(x: 0, y: 0, width: 80, height: 50))
view.backgroundColor = .red
view.onTap {
print("View Tapped")
}
}
我认为你可以简单地使用
UIControl *headerView = ...
[headerView addTarget:self action:@selector(myEvent:) forControlEvents:UIControlEventTouchDown];
我的意思是headerView从UIControl扩展过来。
你们为什么不试试ssevenlistener呢?
您不需要创建任何手势识别器，并将您的逻辑分离到另一个方法。ssevenlistener支持在视图上设置侦听器块，以侦听单个点击手势，双击手势和N-tap手势，如果你喜欢，和长按手势。设置一个点击手势监听器是这样的:
[view ss_addTapViewEventListener:^(UITapGestureRecognizer *recognizer){…} numberOfTapsRequired: 1);
创建一个手势识别器(子类)，它将实现触摸事件，如touchesBegan。之后可以将其添加到视图中。
这样您将使用组合而不是子类化(这是请求)。
