【发布时间】：2017-11-29 15:58:12
【问题描述】：
我创建了一个包含 UILongPressGestureRecognizer 的自定义 Label 类，我在 TableViewController 的 tableview 单元格中调用它。长按手势识别器有效（属性字符串中有两个可点击区域），但如果滚动手势从我的 CustomLabel 的 UILongPressGestureRecognizer 区域之一开始，则包含标签的 tableView 不再滚动（平移）。我试过cancelsTouchesInView = false 以及下面的各种回复，但无济于事。任何建议将不胜感激。我花了一个星期来解决这个问题。我的代码如下。
这是 CustomLabel 类：
class CustomLabel: UILabel {
let layoutManager = NSLayoutManager()
let textContainer = NSTextContainer(size: CGSize.zero)
var textStorage = NSTextStorage() {
didSet {
textStorage.addLayoutManager(layoutManager)
}
}
var onCharacterTapped: ((_ label: UILabel, _ characterIndex: Int, _ state: Bool) -> Void)?
let tapGesture = UILongPressGestureRecognizer()
override var attributedText: NSAttributedString? {
didSet {
if let attributedText = attributedText {
if attributedText.string != textStorage.string {
textStorage = NSTextStorage(attributedString: attributedText)
DispatchQueue.main.async {
let characterDelay = TimeInterval(0.01 + Float(arc4random()) / Float(UInt32.max)) / 100
for (index, char) in attributedText.string.characters.enumerated() {
DispatchQueue.main.asyncAfter(deadline: .now() + characterDelay * Double(index)) {
print("character ch is: \(char) at index: \(index)")
super.attributedText = attributedText.attributedSubstring(from: NSRange(location: 0, length: index+1))
}
}
}
}
} else {
textStorage = NSTextStorage()
}
}
}
override var lineBreakMode: NSLineBreakMode {
didSet {
textContainer.lineBreakMode = lineBreakMode
}
}
override var numberOfLines: Int {
didSet {
textContainer.maximumNumberOfLines = numberOfLines
}
}
required init?(coder aDecoder: NSCoder) {
super.init(coder: aDecoder)
setUp()
}
override init(frame: CGRect) {
super.init(frame: frame)
setUp()
}
func setUp() {
isUserInteractionEnabled = true
layoutManager.addTextContainer(textContainer)
textContainer.lineFragmentPadding = 0
textContainer.lineBreakMode = lineBreakMode
textContainer.maximumNumberOfLines = numberOfLines
tapGesture.addTarget(self, action: #selector(CustomLabel.labelTapped(_:)))
tapGesture.minimumPressDuration = 0
tapGesture.cancelsTouchesInView = false
//tapGesture.delegate = self.superview
addGestureRecognizer(tapGesture)
}
override func layoutSubviews() {
super.layoutSubviews()
textContainer.size = bounds.size
}
func labelTapped(_ gesture: UILongPressGestureRecognizer) {
let locationOfTouch = gesture.location(in: gesture.view)
let textBoundingBox = layoutManager.usedRect(for: textContainer)
let textContainerOffset = CGPoint(x: (bounds.width - textBoundingBox.width) / 2 - textBoundingBox.minX, y: (bounds.height - textBoundingBox.height) / 2 - textBoundingBox.minY)
let locationOfTouchInTextContainer = CGPoint(x: locationOfTouch.x - textContainerOffset.x, y: locationOfTouch.y - textContainerOffset.y)
let indexOfCharacter = layoutManager.characterIndex(for: locationOfTouchInTextContainer, in: textContainer, fractionOfDistanceBetweenInsertionPoints: nil)
if gesture.state == .began {
onCharacterTapped?(self, indexOfCharacter, true)
} else if gesture.state == .ended {
onCharacterTapped?(self, indexOfCharacter, false)
}
}
}
这是cellClass：
class friendTextCell: UITableViewCell {
@IBOutlet weak var labelText: CustomLabel!
override func awakeFromNib() {
super.awakeFromNib()
self.layoutIfNeeded()
}
}
这里是来自创建 CustomCells 的 TableViewControllerClass 的选择：
class UsersViewController: UITableViewController, UIGestureRecognizerDelegate {
private func gestureRecognizer(gestureRecognizer: UIPanGestureRecognizer, shouldRecognizeSimultaneouslyWithGestureRecognizer otherGestureRecognizer: UILongPressGestureRecognizer) -> Bool {return true}
func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRequireFailureOf otherGestureRecognizer: UIGestureRecognizer) -> Bool {
return gestureRecognizer === longPressRecognizer &&
(otherGestureRecognizer.view?.isDescendant(of:tableView) ?? false)
}
override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "friendText", for: indexPath) as! friendTextCell
print("keyArrrrray is: \(keyArray)")
if indexPath.section == 0 && indexPath.row < keyArray.count {
self.removeInstructions()
cell.labelText.font = cell.labelText.font.withSize(17)
let text = "> "+namesArray[indexPath.row] + ": " + linkArray[indexPath.row]
let name = namesArray[indexPath.row]
let link = linkArray[indexPath.row]
let imageLink = imageURLArray[indexPath.row]
let nameChCount = name.characters.count
let linkChCount = link.characters.count
let attributedString = NSMutableAttributedString(string: name + ": " + link, attributes: nil)
let totalChCount = attributedString.string.characters.count
let linkRange = NSMakeRange(0, nameChCount) // for the word "link" in the string above
let linkAttributes: [String : AnyObject] = [
NSForegroundColorAttributeName : UIColor.white, NSUnderlineStyleAttributeName : NSUnderlineStyle.styleSingle.rawValue as AnyObject]
attributedString.setAttributes(linkAttributes, range:linkRange)
cell.labelText.attributedText = attributedString
cell.labelText.onCharacterTapped = { label, characterIndex, state in
let highlight: [String : AnyObject] = [NSForegroundColorAttributeName : UIColor.black, NSBackgroundColorAttributeName : UIColor.white]
if state == true {
if characterIndex < nameChCount {
print("name press began at character \(characterIndex)")
attributedString.addAttributes(highlight, range:NSMakeRange(0, nameChCount))
cell.labelText.attributedText = attributedString
} else if characterIndex > nameChCount {
print("link press began at character \(characterIndex)")
let startPos = nameChCount + 2
let endPos = totalChCount-nameChCount-2
attributedString.addAttributes(highlight, range:NSMakeRange(startPos, endPos))
cell.labelText.attributedText = attributedString
}
} else if state == false {
if characterIndex < name.characters.count {
if let userVC:UserViewTableViewController = self.storyboard?.instantiateViewController(withIdentifier: "UserVC") as? UserViewTableViewController {
userVC.userName = name
userVC.shareLink = link
userVC.imageLink = imageLink
self.navigationController?.pushViewController(userVC, animated: true)
}
}
if characterIndex > name.characters.count && characterIndex <= link.characters.count + name.characters.count {
//extract link from array
let link = self.linkArray[indexPath.row]
print("on click link is: \(link)")
//Present SafariViewController with link
let svc = SFSafariViewController(url: NSURL(string: link)! as URL)
self.present(svc, animated: true, completion: nil)
}
}
}
} else if keyArray.isEmpty && indexPath.section == 0 {
cell.labelText.text = "..."
}
if indexPath.section == 1 && keyArray.count <= 1 {
let message = "> Press the + button to add more friends."
cell.labelText.animate(newText: message, characterDelay: TimeInterval(0.01 + Float(arc4random()) / Float(UInt32.max)) / 200)
} else if indexPath.section == 1 {
cell.labelText.text = ""
}
return cell
}
【问题讨论】：
-
尝试实现名为
optional public func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool的UIGestureRecognizerDelegate方法返回true -
感谢您的回复。我在 CustomCell 类和 tableViewController 类中也试过这个。没用。你会把这个方法放在哪里？
-
我会发布一些例子
-
@ReinierMelian，我在上面的问题中添加了更多代码，因为我的问题似乎源于无法在 tableViewController 类和 CustomLabel 类之间进行通信......？
-
问题是
tableView.panGestureRecognizer.delegate不能分配给viewController
标签： ios swift uilabel uitapgesturerecognizer