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
在iOS 3.2及更高版本中，你可以使用手势识别器。例如，这是你处理点击事件的方式:
//The setup code (in viewDidLoad in your view controller)
UITapGestureRecognizer *singleFingerTap =
[[UITapGestureRecognizer alloc] initWithTarget:self
action:@selector(handleSingleTap:)];
[self.view addGestureRecognizer:singleFingerTap];
//The event handling method
- (void)handleSingleTap:(UITapGestureRecognizer *)recognizer
{
CGPoint location = [recognizer locationInView:[recognizer.view superview]];
//Do stuff here...
}
还有一些内置的手势。查看iOS事件处理和UIGestureRecognizer的文档。我还在github上有一堆示例代码，可能会有所帮助。
其他回答
手势识别器
有许多常用的触摸事件(或手势)，当你添加一个手势识别器到你的视图时，你可以得到通知。默认支持以下手势类型:
UITapGestureRecognizer轻触(简单触摸屏幕一次或多次) UILongPressGestureRecognizer长触(长时间触屏) UIPanGestureRecognizer Pan(在屏幕上移动手指) 滑动(快速移动手指) UIPinchGestureRecognizer捏(将两个手指放在一起或分开-通常是缩放) UIRotationGestureRecognizer旋转(沿圆周方向移动两个手指)
除此之外，你还可以制作自己的手势识别器。
在接口生成器中添加一个手势
将一个手势识别器从对象库拖到视图上。
控件从文档大纲中的手势拖到视图控制器代码中，以创建Outlet和Action。
这应该在默认情况下设置，但也要确保为视图将User Action Enabled设置为true。
以编程方式添加手势
要以编程方式添加一个手势，你(1)创建一个手势识别器，(2)将它添加到视图中，(3)创建一个方法，当手势被识别时调用该方法。
import UIKit
class ViewController: UIViewController {
@IBOutlet weak var myView: UIView!
override func viewDidLoad() {
super.viewDidLoad()
// 1. create a gesture recognizer (tap gesture)
let tapGesture = UITapGestureRecognizer(target: self, action: #selector(handleTap(sender:)))
// 2. add the gesture recognizer to a view
myView.addGestureRecognizer(tapGesture)
}
// 3. this method is called when a tap is recognized
@objc func handleTap(sender: UITapGestureRecognizer) {
print("tap")
}
}
笔记
sender参数为可选参数。如果你不需要一个手势的引用，那么你可以把它去掉。如果你这样做，但是，删除(sender:)后的动作方法名称。 handleTap方法的命名是任意的。使用action: #selector(someMethodName(sender:))将其命名为任何您想要的名称。
更多的例子
您可以研究我添加到这些视图中的手势识别器，以了解它们是如何工作的。
下面是该项目的代码:
import UIKit
class ViewController: UIViewController {
@IBOutlet weak var tapView: UIView!
@IBOutlet weak var doubleTapView: UIView!
@IBOutlet weak var longPressView: UIView!
@IBOutlet weak var panView: UIView!
@IBOutlet weak var swipeView: UIView!
@IBOutlet weak var pinchView: UIView!
@IBOutlet weak var rotateView: UIView!
@IBOutlet weak var label: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
// Tap
let tapGesture = UITapGestureRecognizer(target: self, action: #selector(handleTap))
tapView.addGestureRecognizer(tapGesture)
// Double Tap
let doubleTapGesture = UITapGestureRecognizer(target: self, action: #selector(handleDoubleTap))
doubleTapGesture.numberOfTapsRequired = 2
doubleTapView.addGestureRecognizer(doubleTapGesture)
// Long Press
let longPressGesture = UILongPressGestureRecognizer(target: self, action: #selector(handleLongPress(gesture:)))
longPressView.addGestureRecognizer(longPressGesture)
// Pan
let panGesture = UIPanGestureRecognizer(target: self, action: #selector(handlePan(gesture:)))
panView.addGestureRecognizer(panGesture)
// Swipe (right and left)
let swipeRightGesture = UISwipeGestureRecognizer(target: self, action: #selector(handleSwipe(gesture:)))
let swipeLeftGesture = UISwipeGestureRecognizer(target: self, action: #selector(handleSwipe(gesture:)))
swipeRightGesture.direction = UISwipeGestureRecognizerDirection.right
swipeLeftGesture.direction = UISwipeGestureRecognizerDirection.left
swipeView.addGestureRecognizer(swipeRightGesture)
swipeView.addGestureRecognizer(swipeLeftGesture)
// Pinch
let pinchGesture = UIPinchGestureRecognizer(target: self, action: #selector(handlePinch(gesture:)))
pinchView.addGestureRecognizer(pinchGesture)
// Rotate
let rotateGesture = UIRotationGestureRecognizer(target: self, action: #selector(handleRotate(gesture:)))
rotateView.addGestureRecognizer(rotateGesture)
}
// Tap action
@objc func handleTap() {
label.text = "Tap recognized"
// example task: change background color
if tapView.backgroundColor == UIColor.blue {
tapView.backgroundColor = UIColor.red
} else {
tapView.backgroundColor = UIColor.blue
}
}
// Double tap action
@objc func handleDoubleTap() {
label.text = "Double tap recognized"
// example task: change background color
if doubleTapView.backgroundColor == UIColor.yellow {
doubleTapView.backgroundColor = UIColor.green
} else {
doubleTapView.backgroundColor = UIColor.yellow
}
}
// Long press action
@objc func handleLongPress(gesture: UILongPressGestureRecognizer) {
label.text = "Long press recognized"
// example task: show an alert
if gesture.state == UIGestureRecognizerState.began {
let alert = UIAlertController(title: "Long Press", message: "Can I help you?", preferredStyle: UIAlertControllerStyle.alert)
alert.addAction(UIAlertAction(title: "OK", style: UIAlertActionStyle.default, handler: nil))
self.present(alert, animated: true, completion: nil)
}
}
// Pan action
@objc func handlePan(gesture: UIPanGestureRecognizer) {
label.text = "Pan recognized"
// example task: drag view
let location = gesture.location(in: view) // root view
panView.center = location
}
// Swipe action
@objc func handleSwipe(gesture: UISwipeGestureRecognizer) {
label.text = "Swipe recognized"
// example task: animate view off screen
let originalLocation = swipeView.center
if gesture.direction == UISwipeGestureRecognizerDirection.right {
UIView.animate(withDuration: 0.5, animations: {
self.swipeView.center.x += self.view.bounds.width
}, completion: { (value: Bool) in
self.swipeView.center = originalLocation
})
} else if gesture.direction == UISwipeGestureRecognizerDirection.left {
UIView.animate(withDuration: 0.5, animations: {
self.swipeView.center.x -= self.view.bounds.width
}, completion: { (value: Bool) in
self.swipeView.center = originalLocation
})
}
}
// Pinch action
@objc func handlePinch(gesture: UIPinchGestureRecognizer) {
label.text = "Pinch recognized"
if gesture.state == UIGestureRecognizerState.changed {
let transform = CGAffineTransform(scaleX: gesture.scale, y: gesture.scale)
pinchView.transform = transform
}
}
// Rotate action
@objc func handleRotate(gesture: UIRotationGestureRecognizer) {
label.text = "Rotate recognized"
if gesture.state == UIGestureRecognizerState.changed {
let transform = CGAffineTransform(rotationAngle: gesture.rotation)
rotateView.transform = transform
}
}
}
笔记
You can add multiple gesture recognizers to a single view. For the sake of simplicity, though, I didn't do that (except for the swipe gesture). If you need to for your project, you should read the gesture recognizer documentation. It is fairly understandable and helpful. Known issues with my examples above: (1) Pan view resets its frame on next gesture event. (2) Swipe view comes from the wrong direction on the first swipe. (These bugs in my examples should not affect your understanding of how Gestures Recognizers work, though.)
另一种方法是向视图添加一个透明按钮
UIButton *b = [UIButton buttonWithType:UIButtonTypeCustom];
b.frame = CGRectMake(0, 0, headerView.width, headerView.height);
[headerView addSubview:b];
[b addTarget:self action:@selector(buttonClicked:) forControlEvents:UIControlEventTouchDown];
然后，handle click:
- (void)buttonClicked:(id)sender
{}
在iOS 3.2及更高版本中，你可以使用手势识别器。例如，这是你处理点击事件的方式:
//The setup code (in viewDidLoad in your view controller)
UITapGestureRecognizer *singleFingerTap =
[[UITapGestureRecognizer alloc] initWithTarget:self
action:@selector(handleSingleTap:)];
[self.view addGestureRecognizer:singleFingerTap];
//The event handling method
- (void)handleSingleTap:(UITapGestureRecognizer *)recognizer
{
CGPoint location = [recognizer locationInView:[recognizer.view superview]];
//Do stuff here...
}
还有一些内置的手势。查看iOS事件处理和UIGestureRecognizer的文档。我还在github上有一堆示例代码，可能会有所帮助。
这是ios tapgesture; 首先，你需要为GestureRecognizer创建动作，在动作下面写如下所示的代码
- (IBAction)tapgesture:(id)sender
{
[_password resignFirstResponder];
[_username resignFirstResponder];
NSLog(@" TapGestureRecognizer 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。
