UISearchBar's text move to bottom when input content? - ios

Question

I customized a UISearchbar, the code is like this:
class CustomSearchBar: UIView {
lazy var searchBar: MySearchBar = {
let search = MySearchBar()
search.tintColor = UIColor.orange
search.barTintColor = UIColor.yellow
search.searchBarStyle = .minimal
search.searchTextPositionAdjustment = UIOffset(horizontal: 10, vertical: 0)
return search
}()
lazy var cancelButton: UIButton = {
let button = UIButton(type: .custom)
button.setTitle("取消", for: .normal)
button.setTitleColor(UIColor.black, for: .normal)
return button
}()
override init(frame: CGRect) {
super.init(frame: frame)
setupUI()
setupConstraints()
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
private func setupUI() {
addSubview(searchBar)
addSubview(cancelButton)
}
private func setupConstraints() {
searchBar.snp.makeConstraints { (make) in
make.left.equalToSuperview().offset(20)
make.top.equalToSuperview().offset(6)
make.height.equalTo(32)
make.width.equalToSuperview().offset(-80)
}
cancelButton.snp.makeConstraints { (make) in
make.left.equalTo(searchBar.snp.right).offset(13)
make.centerY.equalTo(searchBar)
}
}
}
class MySearchBar: UISearchBar {
override init(frame: CGRect) {
super.init(frame: frame)
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
func indexOfSearchFieldInSubviews() -> Int! {
var index: Int!
let searchBarView = subviews[0]
for (i, view) in searchBarView.subviews.enumerated() {
if view.isKind(of: UITextField.self) {
index = i
break
}
}
return index
}
override func draw(_ rect: CGRect) {
if let index = indexOfSearchFieldInSubviews() {
let searchField: UITextField = subviews[0].subviews[index] as! UITextField
searchField.leftView = UIImageView(image: UIImage(named: "Search_icon"))
searchField.font = UIFont.systemFont(ofSize: 14)
searchField.borderStyle = .none
searchField.layer.masksToBounds = true
searchField.layer.cornerRadius = 4
searchField.backgroundColor = barTintColor
searchField.contentVerticalAlignment = .center
searchField.placeholder = "input something"
}
}
}
we can see that it is very simple. Just added a searchBar and cancelButton.
Then I added it to navigationBar as subView, make it becomeFirstResponder in viewController.
class ViewController: UIViewController {
lazy var customeSearchBar = CustomSearchBar()
override func viewDidLoad() {
super.viewDidLoad()
navigationController?.navigationBar.addSubview(customeSearchBar)
customeSearchBar.snp.makeConstraints { (make) in
make.left.right.equalToSuperview()
make.centerY.equalToSuperview()
make.height.equalTo(44)
}
customeSearchBar.searchBar.becomeFirstResponder()
}
}
At first, I input content is ok.
When I continue input content, then the issue shows up:
It looks like the content move to the bottom. I tried to find something to fix the problem. But I didn't get it.
It is a strange thing that works fine in simulate and some iPhone. But one of my phone works wrong.