我使用Xcode 8.0和swift 2.3。
我有一个scrollView，我想使用segment来控制页面
scrollView中有两个tableView
但这是函数中的错误：
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
康斯坦特＆＃39; cell＆＃39;在初始化之前使用
这是错误
这是初始化＆＃39; cell＆＃39;，对吧？
let cell:UITableViewCell?
以上是我的代码
class DetailViewController: UIViewController, UITableViewDataSource, UITableViewDelegate, UIScrollViewDelegate {
@IBOutlet weak var scroll: UIScrollView!
@IBOutlet weak var segmentControl2: UISegmentedControl!
@IBOutlet var recipesImageView: UIImageView!
@IBOutlet var tableView:UITableView!
@IBOutlet var tableView1:UITableView!
var recipes:Recipe!
var noodles:Recipe!
var snacks:Recipe!
var category: Int = Int()
@IBAction func segmented(sender: AnyObject) {
switch sender.selectedSegmentIndex {
case 0:
scroll.setContentOffset(CGPoint(x:0, y:0), animated: true)
case 1:
scroll.setContentOffset(CGPoint(x:375, y:0), animated: true)
case 2:
scroll.setContentOffset(CGPoint(x:750, y:0), animated: true)
case 3:
scroll.setContentOffset(CGPoint(x:1125, y:0), animated: true)
default:
print()
}
}
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
switch self.category {
case 0:
self.recipesImageView.image = UIImage(named: recipes.image)
title = self.recipes.name
case 1:
self.recipesImageView.image = UIImage(named: noodles.image)
title = self.noodles.name
case 2:
self.recipesImageView.image = UIImage(named: snacks.image)
title = self.snacks.name
case 3:
self.recipesImageView.image = UIImage(named: noodles.image)
title = self.noodles.name
case 4:
self.recipesImageView.image = UIImage(named: noodles.image)
title = self.noodles.name
default:
self.recipesImageView.image = UIImage(named: recipes.image)
title = self.recipes.name
}
self.tableView.backgroundColor = UIColor(red: 240.0/255.0, green: 240.0/255.0, blue: 240.0/255.0, alpha: 0.5)
//刪除多餘的隔線
self.tableView.tableFooterView = UIView(frame: CGRectZero)
self.tableView.separatorColor = UIColor(red: 240.0/255.0, green: 240.0/255.0, blue: 240.0/255.0, alpha: 1)
//title = self.recipes.name
tableView.estimatedRowHeight = 36.0;
tableView.rowHeight = UITableViewAutomaticDimension;
tableView.dataSource = self
tableView.delegate = self
tableView.registerClass(UITableViewCell.self, forCellReuseIdentifier: "Cell")
tableView1.dataSource = self
tableView1.delegate = self
tableView1.registerClass(UITableViewCell.self, forCellReuseIdentifier: "Cell1")
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
var cellNum:Int?
if tableView == self.tableView {
cellNum = 4
//return cellNum
}
if tableView == self.tableView1 {
cellNum = 1
}
return cellNum!
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell:UITableViewCell?
if tableView == self.tableView {
let cell = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as! DetailTableViewCell
//cell.backgroundColor = UIColor.clearColor()
if self.category == 0 {
switch indexPath.row {
case 0:
cell.fieldLabel.text = "名稱"
cell.valueLabel.text = recipes.name
cell.amountLabel.text = ""
case 1:
cell.fieldLabel.text = "類型"
cell.valueLabel.text = recipes.type
cell.amountLabel.text = ""
case 2:
cell.fieldLabel.text = "收藏"
cell.valueLabel.text = (recipes.isFavor) ? "Yes" : "No"
cell.amountLabel.text = ""
case 3:
cell.fieldLabel.text = "食材"
cell.valueLabel.text = recipes.material
cell.amountLabel.text = recipes.amount
default:
cell.fieldLabel.text = ""
cell.valueLabel.text = ""
cell.amountLabel.text = ""
}
}
if self.category == 1 {
switch indexPath.row {
case 0:
cell.fieldLabel.text = "名稱"
cell.valueLabel.text = noodles.name
cell.amountLabel.text = ""
case 1:
cell.fieldLabel.text = "類型"
cell.valueLabel.text = noodles.type
cell.amountLabel.text = ""
case 2:
cell.fieldLabel.text = "收藏"
cell.valueLabel.text = (noodles.isFavor) ? "Yes" : "No"
cell.amountLabel.text = ""
case 3:
cell.fieldLabel.text = "食材"
cell.valueLabel.text = noodles.material
cell.amountLabel.text = noodles.amount
default:
cell.fieldLabel.text = ""
cell.valueLabel.text = ""
cell.amountLabel.text = ""
}
}
if self.category == 2 {
switch indexPath.row {
case 0:
cell.fieldLabel.text = "名稱"
cell.valueLabel.text = snacks.name
cell.amountLabel.text = ""
case 1:
cell.fieldLabel.text = "類型"
cell.valueLabel.text = snacks.type
cell.amountLabel.text = ""
case 2:
cell.fieldLabel.text = "收藏"
cell.valueLabel.text = (snacks.isFavor) ? "Yes" : "No"
cell.amountLabel.text = ""
case 3:
cell.fieldLabel.text = "食材"
cell.valueLabel.text = snacks.material
cell.amountLabel.text = snacks.amount
default:
cell.fieldLabel.text = ""
cell.valueLabel.text = ""
cell.amountLabel.text = ""
}
}
if self.category == 3 {
switch indexPath.row {
case 0:
cell.fieldLabel.text = "名稱"
cell.valueLabel.text = noodles.name
cell.amountLabel.text = ""
case 1:
cell.fieldLabel.text = "類型"
cell.valueLabel.text = noodles.type
cell.amountLabel.text = ""
case 2:
cell.fieldLabel.text = "收藏"
cell.valueLabel.text = (noodles.isFavor) ? "Yes" : "No"
cell.amountLabel.text = ""
case 3:
cell.fieldLabel.text = "食材"
cell.valueLabel.text = noodles.material
cell.amountLabel.text = noodles.amount
default:
cell.fieldLabel.text = ""
cell.valueLabel.text = ""
cell.amountLabel.text = ""
}
}
if self.category == 4 {
switch indexPath.row {
case 0:
cell.fieldLabel.text = "名稱"
cell.valueLabel.text = noodles.name
cell.amountLabel.text = ""
case 1:
cell.fieldLabel.text = "類型"
cell.valueLabel.text = noodles.type
cell.amountLabel.text = ""
case 2:
cell.fieldLabel.text = "收藏"
cell.valueLabel.text = (noodles.isFavor) ? "Yes" : "No"
cell.amountLabel.text = ""
case 3:
cell.fieldLabel.text = "食材"
cell.valueLabel.text = noodles.material
cell.amountLabel.text = noodles.amount
default:
cell.fieldLabel.text = ""
cell.valueLabel.text = ""
cell.amountLabel.text = ""
}
}
//return cell
}
if tableView == self.tableView1 {
let cell = tableView1.dequeueReusableCellWithIdentifier("Cell1", forIndexPath: indexPath) as! DetailTableViewCell
if self.category == 0 {
switch indexPath.row {
case 0:
cell.materialLabel!.text = recipes.material
default:
cell.materialLabel!.text = recipes.material
}
}
if self.category == 1 {
switch indexPath.row {
case 0:
cell.materialLabel!.text = noodles.material
default:
cell.materialLabel!.text = noodles.material
}
}
if self.category == 2 {
switch indexPath.row {
case 0:
cell.materialLabel!.text = snacks.material
default:
cell.materialLabel!.text = snacks.material
}
}
if self.category == 3 {
switch indexPath.row {
case 0:
cell.materialLabel!.text = noodles.material
default:
cell.materialLabel!.text = noodles.material
}
}
if self.category == 4 {
switch indexPath.row {
case 0:
cell.materialLabel!.text = noodles.material
default:
cell.materialLabel!.text = noodles.material
}
}
}
return cell //<----This line will error ***********************
}
//避免被前面一頁的隱藏導覽列所影響
override func viewWillAppear(animated: Bool) {
super.viewWillAppear(animated)
self.navigationController?.hidesBarsOnSwipe = false
self.navigationController?.setNavigationBarHidden(false, animated: true)
}
/*
// MARK: - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
// Get the new view controller using segue.destinationViewController.
// Pass the selected object to the new view controller.
}
*/
}
答案 0 :(得分：0)
我相信这些改变应该有所帮助：
将let cell:UITableViewCell?更改为let cell:UITableViewCell。该功能并不希望您返回可选项。
将let cell = tableView.dequeue...更改为cell = tableView.dequeue...。你不应该两次声明cell。
将cellForRowAtIndexPath内的结构更新为：
if tableView == self.tableView {
cell = ...
...
} else {
cell = ...
...
}
return cell
因此编译器会在返回之前看到你总是设置单元格。
答案 1 :(得分：0)
您应该使用var并设置为nil。然后也不要在if-else条件内重新初始化。
var cell: UITableViewCell? = nil
if tableView == self.tableView {
cell = tableView1.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as! DetailTableViewCell
// other lines of codes
}
if tableView == self.tableView1 {
cell = tableView1.dequeueReusableCellWithIdentifier("Cell1", forIndexPath: indexPath) as! DetailTableViewCell
// other lines of codes
}