iOS 檢測點擊並觸摸 UIView

Question

我遇到了確定如何檢測 UIView 被觸碰和 UIView 被點擊的問題。 當它觸地時，我希望 UIView 改變它的背景顏色。 當它被觸摸時，我希望 UIView 執行某些任務。 我想知道如何解決這個問題。

-(void)viewDidLoad
{        
    UITapGestureRecognizer *dismissGestureRecognition = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(handleDismissDoubleTap:)];
    dismissGestureRecognition.numberOfTapsRequired = 1;
    [sectionDismissDoubleView addGestureRecognizer:dismissGestureRecognition];

    UITapGestureRecognizer *dismissGestureDownRecognition = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(dismissGestureDownRecognition:)];
    dismissGestureRecognition.numberOfTouchesRequired = 1;
    [sectionDismissDoubleView addGestureRecognizer:dismissGestureDownRecognition];
}

- (void)handleDismissDoubleTap:(UIGestureRecognizer*)tap {
    SettingsDismissDoubleViewController *settingsDouble = [[SettingsDismissDoubleViewController alloc] initWithNibName:@"SettingsDismissDoubleViewController" bundle:nil];
    [self.navigationController pushViewController:settingsDouble animated:YES];
}

- (void)dismissGestureDownRecognition:(UIGestureRecognizer*)tap {
    NSLog(@"Down");
}

Answer 1

這個方法不需要子類化任何東西。 您只需將UILongPressGestureRecognizer添加到視圖並將minimumPressDuration設置為零。 然后檢查調用手勢事件時的狀態，以查看觸摸事件是開始還是結束。

這是上面示例圖像的整個項目代碼。

import UIKit
class ViewController: UIViewController {
    @IBOutlet weak var myView: UIView!
    override func viewDidLoad() {
        super.viewDidLoad()
        let tap = UILongPressGestureRecognizer(target: self, action: #selector(tapHandler))
        tap.minimumPressDuration = 0
        myView.addGestureRecognizer(tap)
    }

    @objc func tapHandler(gesture: UITapGestureRecognizer) {
        
        // there are seven possible events which must be handled

        if gesture.state == .began {
            myView.backgroundColor = UIColor.darkGray
            return
        }

        if gesture.state == .changed {
            print("very likely, just that the finger wiggled around while the user was holding down the button. generally, just ignore this")
            return
        }

        if gesture.state == .possible || gesture.state == .recognized {
            print("in almost all cases, simply ignore these two, unless you are creating very unusual custom subclasses")
            return
        }

        // the three remaining states are
        // .cancelled, .failed, and .ended
        // in all three cases, must return to the normal button look:
        myView.backgroundColor = UIColor.lightGray
    }
}

感謝這個想法的答案。

Answer 2

手勢識別器可能對您想要的東西來說太過分了。 您可能只想使用-touchesBegan:withEvent:和-touchesEnded:withEvent: 。

這是有缺陷的，但它應該讓你知道你想要做什么。

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    self.touchDown = YES;
    self.backgroundColor = [UIColor redColor];
}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
    // Triggered when touch is released
    if (self.isTouchDown) {
        self.backgroundColor = [UIColor whiteColor];
        self.touchDown = NO;
    }
}

- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
{
    // Triggered if touch leaves view
    if (self.isTouchDown) {
        self.backgroundColor = [UIColor whiteColor];
        self.touchDown = NO;
    }
}

此代碼應該放在您創建的UIView的自定義子類中。 然后使用此自定義視圖類型而不是UIView ，您將獲得觸摸處理。

Answer 3

在每個 UIControl 子類（UIButton 等）中，您可以使用它來訂閱一組特定的 UIControlEvent：

addTarget:action:forControlEvents

You should add target with appropriate selector for UIControlEventTouchDown and another target/selector for UIControlEventTouchUpInside event.

界面控件參考

Answer 4

感謝Holly 的回答，我構建了一個ButtonView便利類。

編輯：正如這個答案所說， UILongPressGestureRecognizer反應速度相當快，所以我更新了我的課程。

用法：

let btn = ButtonView()
btn.onNormal = { btn.backgroundColor = .clearColor() }
btn.onPressed = { btn.backgroundColor = .blueColor() }
btn.onReleased = yourAction // Function to be called

班級：

/** View that can be pressed like a button */

import UIKit

class ButtonView : UIView {

    /* Called when the view goes to normal state (set desired appearance) */
    var onNormal = {}
    /* Called when the view goes to pressed state (set desired appearance) */
    var onPressed = {}
    /* Called when the view is released (perform desired action) */
    var onReleased = {}

    override init(frame: CGRect)
    {
        super.init(frame: frame)

        let recognizer = UILongPressGestureRecognizer(target: self, action: Selector("touched:"))
        recognizer.delegate = self
        recognizer.minimumPressDuration = 0.0
        addGestureRecognizer(recognizer)
        userInteractionEnabled = true

        onNormal()
    }

    func touched(sender: UILongPressGestureRecognizer)
    {
        if sender.state == .Began {
            onPressed(self)
        } else if sender.state == .Ended {
            onNormal(self)
            onReleased()
        }
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
}

Answer 5

首先，通過您的選擇器handleDismissDoubleTap: ，我假設您正在尋找雙擊以關閉。 為此，您應該這樣做： dismissGestureRecognition.numberOfTapsRequired = 2;

其次，如果觸摸是指長時間點擊（或“點擊並按住”）類型的手勢，則應使用UILongPressGestureRecognizer而不是UITapGestureRecognizer 。