我在 UIView 中有一个自定义按钮类，我想将其添加到数组中，以便可以轻松访问它们。有没有办法在 Swift 中获取特定类的所有子视图并将其添加到数组中？
使用
filterislet myViews = view.subviews.filter{$0 is MyButtonClass}
MyButtonClass要过滤视图并将其投射为自定义类型，请使用
compactMaplet myViews = view.subviews.compactMap{$0 as? MyButtonClass}
给你
extension UIView {
/** This is the function to get subViews of a view of a particular type
*/
func subViews<T : UIView>(type : T.Type) -> [T]{
var all = [T]()
for view in self.subviews {
if let aView = view as? T{
all.append(aView)
}
}
return all
}
/** This is a function to get subViews of a particular type from view recursively. It would look recursively in all subviews and return back the subviews of the type T */
func allSubViewsOf<T : UIView>(type : T.Type) -> [T]{
var all = [T]()
func getSubview(view: UIView) {
if let aView = view as? T{
all.append(aView)
}
guard view.subviews.count>0 else { return }
view.subviews.forEach{ getSubview(view: $0) }
}
getSubview(view: self)
return all
}
}
你可以这样称呼它
let allSubviews = view.allSubViewsOf(type: UIView.self)
let allLabels = view.allSubViewsOf(type: UILabel.self)
这里的许多答案都不必要地冗长或不够笼统。以下是如何获取视图的所有子视图，在任何深度，属于任何所需的类：
extension UIView {
func subviews<T:UIView>(ofType WhatType:T.Type) -> [T] {
var result = self.subviews.compactMap {$0 as? T}
for sub in self.subviews {
result.append(contentsOf: sub.subviews(ofType:WhatType))
}
return result
}
}
使用方法：
let arr = myView.subviews(ofType: MyButtonClass.self)
要递归地执行此操作（即也获取所有子视图的视图），您可以使用此通用函数：
private func getSubviewsOf<T : UIView>(view:UIView) -> [T] {
var subviews = [T]()
for subview in view.subviews {
subviews += getSubviewsOf(view: subview) as [T]
if let subview = subview as? T {
subviews.append(subview)
}
}
return subviews
}
要获取视图层次结构中的所有 UILabel，只需执行以下操作：
let allLabels : [UILabel] = getSubviewsOf(view: theView)
我现在无法测试它，但这应该可以在 Swift 2 中工作：
view.subviews.flatMap{ $0 as? YourView }
返回一个数组
YourView这是一个经过测试的典型示例，用于计算：
countDots = allDots!.view.subviews.flatMap{$0 as? Dot}.count
从Swift 4.1开始，您可以使用新的compactMap（flatMap现已弃用）：https://developer.apple.com/documentation/swift/sequence/2950916-compactmap （见里面的例子）
根据您的情况，您可以使用：
let buttons:[UIButton] = stackView.subviews.compactMap{ $0 as? UIButton }
您可以使用地图对所有按钮执行操作：
let _ = stackView.subviews.compactMap{ $0 as? UIButton }.map { $0.isSelected = false }
如果您想更新/访问这些特定的子视图，请使用它，
for (index,button) in (view.subviews.filter{$0 is UIButton}).enumerated(){
button.isHidden = false
}
func allSubViews(views: [UIView]) {
for view in views {
if let tf = view as? UITextField {
// Do Something
}
self.allSubViews(views: view.subviews)
}
}
self.allSubViews(views: self.view.subviews)
对于这种情况，我认为我们可以使用 Swift 的
first.wherefilter.countfilter.isEmpty因为当我们使用
filter所以只要检查视图的
subViewslet containsBannerViewKind = view.subviews.first(where: { $0 is BannerView }) != nil
相当于：在该视图的子视图集合中找到与 BannerView 类的第一个匹配项。所以如果这是真的，我们就可以进行进一步的逻辑。
参考：https://github.com/realm/SwiftLint/blob/master/Rules.md#first-where
让我发布我的变体）但这找到了 T 的第一个
extension UIView {
func firstSubView<T: UIView>(ofType type: T.Type) -> T? {
var resultView: T?
for view in subviews {
if let view = view as? T {
resultView = view
break
}
else {
if let foundView = view.firstSubView(ofType: T.self) {
resultView = foundView
break
}
}
}
return resultView
}
}
针对那些喜欢函数式风格的人的递归单行：
extension UIView {
func subviews<T: UIView>(ofType type: T.Type) -> [T] {
subviews.compactMap { $0 as? T } +
subviews.flatMap { $0.subviews(ofType: type) }
}
}
斯威夫特5
func findViewInside<T>(views: [UIView]?, findView: [T] = [], findType: T.Type = T.self) -> [T] {
var findView = findView
let views = views ?? []
guard views.count > .zero else { return findView }
let firstView = views[0]
var loopViews = views.dropFirst()
if let typeView = firstView as? T {
findView = findView + [typeView]
return findViewInside(views: Array(loopViews), findView: findView)
} else if firstView.subviews.count > .zero {
firstView.subviews.forEach { loopViews.append($0) }
return findViewInside(views: Array(loopViews), findView: findView)
} else {
return findViewInside(views: Array(loopViews), findView: findView)
}
}
使用方法：
findViewInside(views: (YourViews), findType: (YourType).self)
我已经浏览了上面的所有答案，它们涵盖了视图当前显示在窗口中的场景，但不提供视图控制器中未显示在窗口中的视图。
基于@matt的答案，我编写了以下函数，它使用下一个响应者递归地遍历所有视图，包括不可见视图控制器、子视图控制器、导航控制器视图控制器
（注意：它可以得到明确的改进，因为它在递归函数之上增加了更多的复杂性。将其视为概念证明）
/// Returns the array of subviews in the view hierarchy which match the provided type, including any hidden
/// - Parameter type: the type filter
/// - Returns: the resulting array of elements matching the given type
func allSubviews<T:UIView>(of type:T.Type) -> [T] {
var result = self.subviews.compactMap({$0 as? T})
var subviews = self.subviews
// *********** Start looking for non-visible view into view controllers ***********
// Inspect also the non visible views on the same level
var notVisibleViews = [UIView]()
subviews.forEach { (v) in
if let vc = v.next as? UIViewController {
let childVCViews = vc.children.filter({$0.isViewLoaded && $0.view.window == nil }).compactMap({$0.view})
notVisibleViews.append(contentsOf: childVCViews)
}
if let vc = v.next as? UINavigationController {
let nvNavVC = vc.viewControllers.filter({$0.isViewLoaded && $0.view.window == nil })
let navVCViews = nvNavVC.compactMap({$0.view})
notVisibleViews.append(contentsOf: navVCViews)
// detect child vc in not visible vc in the nav controller
let childInNvNavVC = nvNavVC.compactMap({$0.children}).reduce([],+).compactMap({$0.view})
notVisibleViews.append(contentsOf: childInNvNavVC)
}
if let vc = v.next as? UITabBarController {
let tabViewControllers = vc.viewControllers?.filter({$0.isViewLoaded && $0.view.window == nil }) ?? [UIViewController]()
// detect navigation controller in the hidden tab bar view controllers
let vc1 = tabViewControllers.compactMap({$0 as? UINavigationController})
vc1.forEach { (vc) in
let nvNavVC = vc.viewControllers.filter({$0.isViewLoaded && $0.view.window == nil })
let navVCViews = nvNavVC.compactMap({$0.view})
notVisibleViews.append(contentsOf: navVCViews)
// detect child vc in not visible vc in the nav controller
let childInNvNavVC = nvNavVC.compactMap({$0.children}).reduce([],+).compactMap({$0.view})
notVisibleViews.append(contentsOf: childInNvNavVC)
}
// ad non-navigation controller in the hidden tab bar view controllers
let tabVCViews = tabViewControllers.compactMap({($0 as? UINavigationController) == nil ? $0.view : nil})
notVisibleViews.append(contentsOf: tabVCViews)
}
}
subviews.append(contentsOf: notVisibleViews.removingDuplicates())
// *********** End looking for non-visible view into view controllers ***********
subviews.forEach({result.append(contentsOf: $0.allSubviews(of: type))})
return result.removingDuplicates()
}
extension Array where Element: Hashable {
func removingDuplicates() -> [Element] {
var dict = [Element: Bool]()
return filter { dict.updateValue(true, forKey: $0) == nil }
}
}
使用示例：
let allButtons = keyWindow.allSubviews(of: UIButton.self)
注意：如果当前存在模态视图控制器，则上述脚本找不到
presentingViewController这种需求可能并不常见，但也许可以帮助别人:)