当前，myTableView包含“一个”，“两个”和“三个”。但是，在用户从上面的下拉选项中同时选择品牌和型号之前，我希望保持空白，并且一旦按下“添加”按钮，我希望将数据传递到myTableView中。
导入UIKit
var myTableView: UITableView = UITableView()
struct Section {
var make: String
var model: [String]
}
var Cars = [
Section(make: "Any", model: ["Any"]),
Section(make: "BMW", model: ["A","B","C"]),
Section(make: "Ford", model: ["D","E","F"]),
Section(make: "Audi", model: ["G","H","I"]),
Section(make: "Bentley", model: ["J","K","L"])
]
var carMake = Cars.map({$0.make})
class ViewController: UIViewController,DropDownBtnProtocol, UITableViewDataSource, UITableViewDelegate {
func optionChanged(_ button: DropDownBtn, string: String) {
if button == makeButton {
if let selectedMake = Cars.first(where: { $0.make == string }) {
modelButton.dropView.dropDownOptions = selectedMake.model
self.view.bringSubviewToFront(modelButton.dropView)
}
} else if button == modelButton {
}
}
////Set up buttons
var makeButton = DropDownBtn()
var modelButton = DropDownBtn()
var addButton = UIButton()
override func viewDidLoad() {
super.viewDidLoad()
navigationItem.title = "Innocent Sheep"
view.backgroundColor = .white
makeButton = DropDownBtn.init(frame: CGRect(x: 0, y: 0, width: 0, height: 0))
makeButton.delegate = self
makeButton.setTitle("Select Make", for: .normal)
makeButton.titleLabel?.font = UIFont.boldSystemFont(ofSize: 17)
makeButton.translatesAutoresizingMaskIntoConstraints = false
self.view.addSubview(makeButton)
makeButton.centerXAnchor.constraint(equalTo: self.view.centerXAnchor).isActive = true
makeButton.centerYAnchor.constraint(equalTo: self.view.centerYAnchor, constant: -300).isActive = true
makeButton.widthAnchor.constraint(equalToConstant: 450).isActive = true
makeButton.heightAnchor.constraint(equalToConstant: 50).isActive = true
makeButton.dropView.dropDownOptions = carMake
modelButton = DropDownBtn.init(frame: CGRect(x: 0, y: 0, width: 0, height: 0))
modelButton.delegate = self
modelButton.setTitle("Select Model", for: .normal)
modelButton.titleLabel?.font = UIFont.boldSystemFont(ofSize: 17)
modelButton.translatesAutoresizingMaskIntoConstraints = false
self.view.addSubview(modelButton)
modelButton.centerXAnchor.constraint(equalTo: self.view.centerXAnchor).isActive = true
modelButton.centerYAnchor.constraint(equalTo: self.view.centerYAnchor, constant: -240).isActive = true
modelButton.widthAnchor.constraint(equalToConstant: 450).isActive = true
modelButton.heightAnchor.constraint(equalToConstant: 50).isActive = true
let addButton = UIButton.init(type: .system)
addButton.frame = CGRect(x: 50, y: 300, width: 60, height: 40)
addButton.layer.cornerRadius = 5
addButton.setTitle("Add", for: .normal)
addButton.layer.borderWidth = 2.5
addButton.layer.borderColor = UIColor.black.cgColor
addButton.addTarget(self, action: #selector(buttonClicked(_ :)), for: .touchUpInside)
self.view.addSubview(addButton)
}
@objc func buttonClicked(_: UIButton) {
print("tapped")
}
var itemsToLoad: [String] = ["One", "Two", "Three"]
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
let screenSize: CGRect = UIScreen.main.bounds
let screenWidth = screenSize.width
let screenHeight = (screenSize.height / 2)
myTableView.frame = CGRect(x: 0, y: 500, width: screenWidth, height: screenHeight)
myTableView.dataSource = self
myTableView.delegate = self
myTableView.register(UITableViewCell.self, forCellReuseIdentifier: "myCell")
self.view.addSubview(myTableView)
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return itemsToLoad.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell: UITableViewCell = tableView.dequeueReusableCell(withIdentifier: "myCell", for: indexPath)
cell.textLabel?.text = self.itemsToLoad[indexPath.row]
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
print("User selected table row \(indexPath.row) and item \(itemsToLoad[indexPath.row])")
}
}
protocol DropDownBtnProtocol {
func optionChanged(_ button: DropDownBtn, string: String)
}
class DropDownBtn: UIButton, DropDownViewProtocol {
func dropDownPressed(string: String) {
self.setTitle(string, for: .normal)
self.dismissMakeDropDown()
delegate.optionChanged(self, string: string)
}
var delegate: DropDownBtnProtocol!
var dropView = DropDownView()
var height = NSLayoutConstraint()
override init(frame: CGRect) {
super.init(frame:frame)
self.backgroundColor = UIColor(red: 52/255, green: 49/255, blue: 78/255, alpha: 1)
dropView = DropDownView.init(frame: CGRect.init(x: 0, y: 0, width: 0, height: 0))
dropView.delegate = self
dropView.translatesAutoresizingMaskIntoConstraints = false
}
override func didMoveToSuperview() {
self.superview?.addSubview(dropView)
self.superview?.bringSubviewToFront(dropView)
dropView.topAnchor.constraint(equalTo: self.bottomAnchor).isActive = true
dropView.centerXAnchor.constraint(equalTo: self.centerXAnchor).isActive = true
dropView.widthAnchor.constraint(equalTo: self.widthAnchor).isActive = true
height = dropView.heightAnchor.constraint(equalToConstant: 0)
}
var makeisOpen = false
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
if makeisOpen == false {
makeisOpen = true
NSLayoutConstraint.deactivate([self.height])
if self.dropView.tableView.contentSize.height > 150 {
self.height.constant = 150
self.superview?.bringSubviewToFront(dropView)
} else {
self.height.constant = self.dropView.tableView.contentSize.height
}
NSLayoutConstraint.activate([self.height])
UIView.animate(withDuration: 0.5, delay: 0,
usingSpringWithDamping: 0.5, initialSpringVelocity: 0.5, options:
.curveEaseInOut, animations: {self.dropView.layoutIfNeeded()
self.dropView.center.y += self.dropView.frame.height / 2
}, completion: nil)
} else {
makeisOpen = false
NSLayoutConstraint.deactivate([self.height])
self.height.constant = 0
NSLayoutConstraint.activate([self.height])
UIView.animate(withDuration: 0.5, delay: 0,
usingSpringWithDamping: 0.5,initialSpringVelocity: 0.5, options:
.curveEaseInOut, animations: {
self.dropView.center.y -= self.dropView.frame.height / 2
self.dropView.layoutIfNeeded()
}, completion: nil)
}
}
func dismissMakeDropDown() {
makeisOpen = false
NSLayoutConstraint.deactivate([self.height])
self.height.constant = 0
NSLayoutConstraint.activate([self.height])
UIView.animate(withDuration: 0.5, delay: 0,
usingSpringWithDamping: 0.5,initialSpringVelocity: 0.5, options:
.curveEaseInOut, animations: {
self.dropView.center.y -= self.dropView.frame.height / 2
self.dropView.layoutIfNeeded()
}, completion: nil)
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
protocol DropDownViewProtocol {
func dropDownPressed(string: String)
}
class DropDownView: UIView, UITableViewDelegate,UITableViewDataSource {
var dropDownOptions = [String]() {
didSet {
tableView.reloadData()
}
}
var tableView = UITableView()
var delegate : DropDownViewProtocol!
override init(frame: CGRect) {
super.init(frame: frame)
tableView.backgroundColor = UIColor.white
self.backgroundColor = UIColor.white
tableView.delegate = self
tableView.dataSource = self
tableView.translatesAutoresizingMaskIntoConstraints = false
self.addSubview(tableView)
tableView.leftAnchor.constraint(equalTo: self.leftAnchor).isActive = true
tableView.rightAnchor.constraint(equalTo: self.rightAnchor).isActive = true
tableView.topAnchor.constraint(equalTo: self.topAnchor).isActive = true
tableView.bottomAnchor.constraint(equalTo: self.bottomAnchor).isActive = true
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return dropDownOptions.count
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath:
IndexPath) -> UITableViewCell {
let cell = UITableViewCell()
cell.textLabel!.text = dropDownOptions[indexPath.row]
cell.backgroundColor = UIColor.init(red: 255/255, green: 160/255, blue: 122/255, alpha: 0.8)
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
self.delegate.dropDownPressed(string: dropDownOptions[indexPath.row])
}
class DropDownView: UIView, UITableViewDelegate,UITableViewDataSource {
var optionstableView = UITableView()
override init(frame: CGRect) {
super.init(frame: frame)
optionstableView.backgroundColor = UIColor.red
self.backgroundColor = UIColor.red
optionstableView.delegate = self
optionstableView.dataSource = self
optionstableView.translatesAutoresizingMaskIntoConstraints = false
self.addSubview(optionstableView)
optionstableView.leftAnchor.constraint(equalTo: optionstableView.leftAnchor, constant: 32).isActive = true
optionstableView.topAnchor.constraint(equalTo: optionstableView.topAnchor, constant: 120).isActive = true
optionstableView.rightAnchor.constraint(equalTo: optionstableView.rightAnchor, constant: -32).isActive = true
optionstableView.bottomAnchor.constraint(equalTo: optionstableView.bottomAnchor, constant: -32).isActive = true
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
func numberOfSections(in tableView: UITableView) -> Int {
return 1
}
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 25
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath:
IndexPath) -> UITableViewCell {
let cell = UITableViewCell()
cell.textLabel!.text = "dropDownOptions[indexPath.row]"
cell.backgroundColor = UIColor.init(red: 255/255, green: 160/255, blue: 122/255, alpha: 0.8)
return cell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
}
}
}
我希望myTableView最初不包含任何值，而不是myTableView显示“一个”，“两个”和“三个”，但是当用户从上述下拉菜单中同时选择品牌和型号时，他们按下“添加”按钮，选择将添加到表格视图中。谢谢。
答案 0 :(得分：0)
首先，我不知道您只是复制粘贴内容还是实际文件看起来像那样。如果您的文件看上去确实像这样，那么您需要学习代码组织的最佳实践并进行一些整理。
第二，不确定是否要添加单元格，部分或其他内容。快速浏览您的代码后，我看到您以编程方式创建了一些很好的约束，但我建议使用自定义视图或自定义UITableViewCell包含自定义视图，并将与其他视图相关的约束放在其中。
因此，让我们回到主题上，如果您只是想让用户在下拉选择中选择两件事，然后插入UITableViewCell，就可以做到。只需添加一些逻辑来处理它，并记住在插入和删除表视图单元格时更新显示数据。但是我建议您在添加更多逻辑之前先清理一下代码。