我们如何实施3D触摸以检查用户是否点击UIView或强制触摸UIView？
有没有办法使用UIGestureRecognize或仅使用UITouch？
答案 0 :(得分：20)
您可以在没有指定手势识别器的情况下执行此操作。您不需要调整touchesEnded和touchesBegan方法，而只需要touchesMoved来获取正确的值。从开始/结束获得uitouch的力量将返回奇怪的值。
UITouch *touch = [touches anyObject];
CGFloat maximumPossibleForce = touch.maximumPossibleForce;
CGFloat force = touch.force;
CGFloat normalizedForce = force/maximumPossibleForce;
然后，设置一个力阈值，并将normalizedForce与此阈值进行比较（0.75对我来说似乎很好）。
答案 1 :(得分：9)
3D Touch属性are available on UITouch objects。
您可以通过覆盖UIView的{{1}}和touchesBegan:方法来获取这些内容。不确定你在touchesMoved:中看到了什么。
如果您愿意创建新的手势识别器，则可以完全访问touchesEnded:中公开的UITouch。
我不确定如何在传统UIGestureRecognizerSubclass中使用3D触控属性。也许是通过UIGestureRecognizer协议的UIGestureRecognizerDelegate方法。
答案 2 :(得分：6)
在Swift 4.2和iOS 12中，解决问题的一种可能方法是创建一个UIGestureRecognizer的自定义子类来处理Force Touch，并将其添加到视图中UITapGestureRecognizer旁边。以下完整的代码显示了如何实现它：
ViewController.swift
import UIKit
class ViewController: UIViewController {
let redView = UIView()
lazy var tapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(tapHandler))
lazy var forceTouchGestureRecognizer = ForceTouchGestureRecognizer(target: self, action: #selector(forceTouchHandler))
override func viewDidLoad() {
super.viewDidLoad()
redView.backgroundColor = .red
redView.addGestureRecognizer(tapGestureRecognizer)
view.addSubview(redView)
redView.translatesAutoresizingMaskIntoConstraints = false
redView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
redView.centerYAnchor.constraint(equalTo: view.centerYAnchor).isActive = true
redView.widthAnchor.constraint(equalToConstant: 100).isActive = true
redView.heightAnchor.constraint(equalToConstant: 100).isActive = true
}
override func traitCollectionDidChange(_ previousTraitCollection: UITraitCollection?) {
super.traitCollectionDidChange(previousTraitCollection)
if traitCollection.forceTouchCapability == UIForceTouchCapability.available {
redView.addGestureRecognizer(forceTouchGestureRecognizer)
} else {
// When force touch is not available, remove force touch gesture recognizer.
// Also implement a fallback if necessary (e.g. a long press gesture recognizer)
redView.removeGestureRecognizer(forceTouchGestureRecognizer)
}
}
@objc func tapHandler(_ sender: UITapGestureRecognizer) {
print("Tap triggered")
}
@objc func forceTouchHandler(_ sender: ForceTouchGestureRecognizer) {
UINotificationFeedbackGenerator().notificationOccurred(.success)
print("Force touch triggered")
}
}
ForceTouchGestureRecognizer.swift
import UIKit.UIGestureRecognizerSubclass
@available(iOS 9.0, *)
final class ForceTouchGestureRecognizer: UIGestureRecognizer {
private let threshold: CGFloat = 0.75
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent) {
super.touchesBegan(touches, with: event)
if let touch = touches.first {
handleTouch(touch)
}
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent) {
super.touchesMoved(touches, with: event)
if let touch = touches.first {
handleTouch(touch)
}
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent) {
super.touchesEnded(touches, with: event)
state = UIGestureRecognizer.State.failed
}
override func touchesCancelled(_ touches: Set<UITouch>, with event: UIEvent) {
super.touchesCancelled(touches, with: event)
state = UIGestureRecognizer.State.failed
}
private func handleTouch(_ touch: UITouch) {
guard touch.force != 0 && touch.maximumPossibleForce != 0 else { return }
if touch.force / touch.maximumPossibleForce >= threshold {
state = UIGestureRecognizer.State.recognized
}
}
}
来源：
答案 3 :(得分：5)
我这样做的方法是使用UITapGestureRecognizer（由Apple提供）和DFContinuousForceTouchGestureRecognizer（由我提供）的组合。
DFContinuousForceTouchGestureRecognizer很好，因为它提供了有关压力变化的持续更新，因此您可以在用户改变压力时增加视图，而不是单个事件。如果您只想要一个活动，则可以忽略DFContinuousForceTouchDelegate中除了- (void) forceTouchRecognized回调之外的其他内容。
https://github.com/foggzilla/DFContinuousForceTouchGestureRecognizer
您可以下载此设备并在支持强制按下的设备上运行示例应用程序以查看其感受。
在UIViewController中实施以下内容：
- (void)viewDidLoad {
[super viewDidLoad];
_forceTouchRecognizer = [[DFContinuousForceTouchGestureRecognizer alloc] init];
_forceTouchRecognizer.forceTouchDelegate = self;
//here to demonstrate how this works alonside a tap gesture recognizer
_tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapped:)];
[self.imageView addGestureRecognizer:_tapGestureRecognizer];
[self.imageView addGestureRecognizer:_forceTouchRecognizer];
}
为点击手势实现选择器
#pragma UITapGestureRecognizer selector
- (void)tapped:(id)sender {
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.1f * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
[[[UIAlertView alloc] initWithTitle:@"Tap" message:@"YEAH!!" delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil] show];
});
}
实施强制触摸的委托协议：
#pragma DFContinuousForceTouchDelegate
- (void)forceTouchRecognized:(DFContinuousForceTouchGestureRecognizer *)recognizer {
self.imageView.transform = CGAffineTransformIdentity;
[self.imageView setNeedsDisplay];
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.1f * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
[[[UIAlertView alloc] initWithTitle:@"Force Touch" message:@"YEAH!!" delegate:nil cancelButtonTitle:@"OK" otherButtonTitles:nil] show];
});
}
- (void)forceTouchRecognizer:(DFContinuousForceTouchGestureRecognizer *)recognizer didStartWithForce:(CGFloat)force maxForce:(CGFloat)maxForce {
CGFloat transformDelta = 1.0f + ((force/maxForce) / 3.0f);
self.imageView.transform = CGAffineTransformMakeScale(transformDelta, transformDelta);
[self.imageView setNeedsDisplay];
}
- (void) forceTouchRecognizer:(DFContinuousForceTouchGestureRecognizer *)recognizer didMoveWithForce:(CGFloat)force maxForce:(CGFloat)maxForce {
CGFloat transformDelta = 1.0f + ((force/maxForce) / 3.0f);
self.imageView.transform = CGAffineTransformMakeScale(transformDelta, transformDelta);
[self.imageView setNeedsDisplay];
}
- (void)forceTouchRecognizer:(DFContinuousForceTouchGestureRecognizer *)recognizer didCancelWithForce:(CGFloat)force maxForce:(CGFloat)maxForce {
self.imageView.transform = CGAffineTransformIdentity;
[self.imageView setNeedsDisplay];
}
- (void)forceTouchRecognizer:(DFContinuousForceTouchGestureRecognizer *)recognizer didEndWithForce:(CGFloat)force maxForce:(CGFloat)maxForce {
self.imageView.transform = CGAffineTransformIdentity;
[self.imageView setNeedsDisplay];
}
- (void)forceTouchDidTimeout:(DFContinuousForceTouchGestureRecognizer *)recognizer {
self.imageView.transform = CGAffineTransformIdentity;
[self.imageView setNeedsDisplay];
}
请注意，这仅适用于支持强制触摸的设备。
此外，如果您在iOS 8或更低版本上运行，则不应将DFContinuousForceTouchGestureRecognizer添加到视图中，因为它使用仅在iOS 9中可用的force上的新UITouch属性。 / p>
如果你在iOS 8上添加它会崩溃，所以如果你支持早于iOS 9的版本，请根据你运行的iOS版本有条件地添加这个识别器。
答案 4 :(得分：5)
我创建了一个模拟Apple Mail应用程序行为的UIGestureRecognizer。在3D触摸时，它以短的单脉冲振动开始，然后是一个可选的辅助动作（hardTarget），并在初始按下后不久通过硬按压调用脉冲。
改编自https://github.com/FlexMonkey/DeepPressGestureRecognizer
的变化：
注意：我添加了未记录的系统声音k_PeakSoundID，但如果您使用超出记录范围的常量感到不舒服，请随时将其关闭。多年来我一直在使用具有未公开常数的系统声音，但欢迎您使用vibrateOnDeepPress属性关闭振动脉冲。
import UIKit
import UIKit.UIGestureRecognizerSubclass
import AudioToolbox
class DeepPressGestureRecognizer: UIGestureRecognizer {
var vibrateOnDeepPress = true
var threshold: CGFloat = 0.75
var hardTriggerMinTime: TimeInterval = 0.5
var onDeepPress: (() -> Void)?
private var deepPressed: Bool = false {
didSet {
if (deepPressed && deepPressed != oldValue) {
onDeepPress?()
}
}
}
private var deepPressedAt: TimeInterval = 0
private var k_PeakSoundID: UInt32 = 1519
private var hardAction: Selector?
private var target: AnyObject?
required init(target: AnyObject?, action: Selector, hardAction: Selector? = nil, threshold: CGFloat = 0.75) {
self.target = target
self.hardAction = hardAction
self.threshold = threshold
super.init(target: target, action: action)
}
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent) {
if let touch = touches.first {
handle(touch: touch)
}
}
override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent) {
if let touch = touches.first {
handle(touch: touch)
}
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent) {
super.touchesEnded(touches, with: event)
state = deepPressed ? UIGestureRecognizerState.ended : UIGestureRecognizerState.failed
deepPressed = false
}
private func handle(touch: UITouch) {
guard let _ = view, touch.force != 0 && touch.maximumPossibleForce != 0 else {
return
}
let forcePercentage = (touch.force / touch.maximumPossibleForce)
let currentTime = Date.timeIntervalSinceReferenceDate
if !deepPressed && forcePercentage >= threshold {
state = UIGestureRecognizerState.began
if vibrateOnDeepPress {
AudioServicesPlaySystemSound(k_PeakSoundID)
}
deepPressedAt = Date.timeIntervalSinceReferenceDate
deepPressed = true
} else if deepPressed && forcePercentage <= 0 {
endGesture()
} else if deepPressed && currentTime - deepPressedAt > hardTriggerMinTime && forcePercentage == 1.0 {
endGesture()
if vibrateOnDeepPress {
AudioServicesPlaySystemSound(k_PeakSoundID)
}
//fire hard press
if let hardAction = self.hardAction, let target = self.target {
_ = target.perform(hardAction, with: self)
}
}
}
func endGesture() {
state = UIGestureRecognizerState.ended
deepPressed = false
}
}
// MARK: DeepPressable protocol extension
protocol DeepPressable {
var gestureRecognizers: [UIGestureRecognizer]? {get set}
func addGestureRecognizer(gestureRecognizer: UIGestureRecognizer)
func removeGestureRecognizer(gestureRecognizer: UIGestureRecognizer)
func setDeepPressAction(target: AnyObject, action: Selector)
func removeDeepPressAction()
}
extension DeepPressable {
func setDeepPressAction(target: AnyObject, action: Selector) {
let deepPressGestureRecognizer = DeepPressGestureRecognizer(target: target, action: action, threshold: 0.75)
self.addGestureRecognizer(gestureRecognizer: deepPressGestureRecognizer)
}
func removeDeepPressAction() {
guard let gestureRecognizers = gestureRecognizers else { return }
for recogniser in gestureRecognizers where recogniser is DeepPressGestureRecognizer {
removeGestureRecognizer(gestureRecognizer: recogniser)
}
}
}