我有一个工作的搜索栏，不知从哪里，我甚至无法激活任何委托方法。我以编程方式创建了搜索栏。
这是我的初始化代码：
self.searchBar.delegate = self
self.searchBar.translatesAutoresizingMaskIntoConstraints = false
self.searchBar.searchBarStyle = .minimal
self.searchBar.isUserInteractionEnabled = true
let image = self.getImageWithColor(color: UIColor(red: 255/255.0, green: 255/255.0, blue: 255/255.0, alpha: 0.19), size: CGSize(width: self.customNavBar.frame.width * 0.9440, height: self.customNavBar.frame.height * 0.47727))
searchBar.setSearchFieldBackgroundImage(image, for: .normal)
self.customNavBar.addSubview(self.searchBar)
var horizCenter = NSLayoutConstraint(item: self.searchBar, attribute: .centerX, relatedBy: .equal, toItem: self.customNavBar, attribute: .centerX, multiplier: 1, constant: 0)
var vertConstraints = NSLayoutConstraint(item: self.searchBar, attribute: .top, relatedBy: .equal, toItem: self.customNavBar, attribute: .top, multiplier: 1, constant: 30)
var widthConstraint = NSLayoutConstraint(item: self.searchBar, attribute: .width, relatedBy: .equal, toItem: self.customNavBar, attribute: .width, multiplier: 0.9440, constant: 0)
var heightConstraint = NSLayoutConstraint(item: self.searchBar, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1, constant: self.customNavBar.frame.height * 0.47727 )
NSLayoutConstraint.activate([horizCenter, vertConstraints, widthConstraint, heightConstraint])
这是我上面引用的getImageWithColor方法：
func getImageWithColor(color: UIColor, size: CGSize) -> UIImage {
let rect = CGRect(x:0, y:0, width:size.width,height: size.height)
let path = UIBezierPath(roundedRect: rect, cornerRadius: 5.0)
UIGraphicsBeginImageContextWithOptions(size, false, 0)
color.setFill()
path.fill()
let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
UIGraphicsEndImageContext()
return image
}
我继续自定义搜索栏中的文本字段：
UITextField.appearance().tintColor = UIColor.white
let cancelButtonAttributes: NSDictionary = [NSForegroundColorAttributeName: UIColor.white, NSFontAttributeName : UIFont(name: "Gotham-Book", size: 14.0)!]
UIBarButtonItem.appearance().setTitleTextAttributes(cancelButtonAttributes as? [String : AnyObject], for: UIControlState.normal)
let textFieldInsideSearchBar = self.searchBar.value(forKey: "searchField") as? UITextField
textFieldInsideSearchBar?.textColor = UIColor(red: 255/255.0, green: 255/255.0, blue: 255/255.0, alpha: 1.0)
textFieldInsideSearchBar?.font = UIFont(name: "Gotham Medium", size: 20.0)
textFieldInsideSearchBar?.clearsOnBeginEditing = true
textFieldInsideSearchBar?.borderStyle = .none
textFieldInsideSearchBar?.clearButtonMode = .whileEditing
textFieldInsideSearchBar?.isUserInteractionEnabled = true
以及我所有的委托方法：
extension ListViewController : UISearchBarDelegate {
func searchBarTextDidBeginEditing(_ searchBar: UISearchBar) {
print("\nfunc searchBarTextDidBeginEditing\n")
self.hideDayDropDown()
UIView.animate(withDuration: 0.25) {
self.dayButton.alpha = 0.0
self.dayButtonLabel.alpha = 0.0
self.dayDropDownArrow.alpha = 0.0
self.mapButton.alpha = 0.0
self.mapButton.isEnabled = false
self.dayButton.isUserInteractionEnabled = false
self.tableView.transform = CGAffineTransform(translationX: 0.0, y: -(self.tableView.frame.minY - self.customNavBar.frame.maxY))
self.tableView.translatesAutoresizingMaskIntoConstraints = true
self.tableView.frame = CGRect(x: 0, y: self.customNavBar.frame.maxY, width: self.view.frame.width, height: 300)
self.dealOfTheDayLabel.alpha = 0.00
self.exploreSpecialView.alpha = 0.0
self.exploreSpecialsLabel.alpha = 0.0
}
searchActive = true
self.searchBar.setShowsCancelButton(true, animated: true)
UIView.animate(withDuration: 0.25) {
self.searchIconImage.alpha = 0.0
self.searchIconWhileEditing.alpha = 1.0
}
}
func searchBarTextDidEndEditing(_ searchBar: UISearchBar) {
print("\nfunc searchBarTextDidEndEditing\n")
UIView.animate(withDuration: 0.25) {
self.dayButton.alpha = 1.0
self.dayButtonLabel.alpha = 1.0
self.dayDropDownArrow.alpha = 1.0
self.dayButton.isUserInteractionEnabled = true
self.searchIconImage.alpha = 1.0
self.searchIconWhileEditing.alpha = 0.0
self.tableView.transform = CGAffineTransform(translationX: 0.0, y: 0.0)
self.tableView.translatesAutoresizingMaskIntoConstraints = false
self.mapButton.alpha = 1.0
self.mapButton.isEnabled = true
self.dealOfTheDayLabel.alpha = 1.0
self.exploreSpecialView.alpha = 1.0
self.exploreSpecialsLabel.alpha = 1.0
}
searchActive = false
}
func searchBarCancelButtonClicked(_ searchBar: UISearchBar) {
print("\nfunc searchBarCancelButtonClicked\n")
self.searchBar.setShowsCancelButton(false, animated: true)
self.searchBar.text = ""
self.searchBar.resignFirstResponder()
searchActive = false
self.searchIconImage.alpha = 1.0
self.searchIconWhileEditing.alpha = 0.0
self.dayDropDownArrow.alpha = 1.0
self.tableView.transform = CGAffineTransform(translationX: 0.0, y: 0.0 )
self.dealOfTheDayLabel.alpha = 1.0
self.exploreSpecialView.alpha = 1.0
self.exploreSpecialsLabel.alpha = 1.0
tableView.reloadData()
}
func searchBar(_ searchBar: UISearchBar, textDidChange searchText: String) {
self.searchResults = self.library.filter({ (bar: BarLibrary) -> Bool in
let tmp: String = bar.name!
let range = tmp.localizedLowercase.range(of: searchText.localizedLowercase)
return range != nil
})
if(self.searchResults.count == 0){
searchActive = false
} else {
searchActive = true
}
self.tableView.reloadData()
}
}
下面是我的导航栏和搜索栏的界面截图：
界面捕获中的屏幕捕获图像：从前到后查看名称：
UITextFieldBorderView，UISearchBarTextField，UIView，UISearchBar，UIView注意，我不确定
UISearchBar之前的UISearchBar是用来做什么的我知道有很多问题，所以为什么其他人不能访问他们的委托方法。这些解决方案对我都不起作用。为什么到目前为止我不能访问委托方法？
最佳答案：
如果委托方法都不起作用，我猜是因为某种原因，您的searchBarDelegate正在被释放，很难说不看到整个代码，但是一定要保持对searchBarDelegate的强引用，因为委托本身是弱的，这意味着如果没有其他人保留它，它可以被释放，因此没有委托来响应调用。
