我有一个shoppingList应用程序 当您将项目添加到类别列表时,它会添加到整个类别列表时不应该!
https://github.com/mrbryankmiller/Grocery-TableView-.git
class GroceryItemsTableViewController: UITableViewController {
//var groceryItem = ["Item1", "Item2", "Item3"]
//var groceryList = ["Breakfast","Lunch", "Dinner"]
@IBOutlet var groceryItemTableView: UITableView!
@IBAction func addGroceryItemButtonPressed(sender: UIBarButtonItem) {
///new way///
let alertController: UIAlertController = UIAlertController(title: "Add Grocery Item", message: "", preferredStyle: .Alert)
//Cancel Button
let cancelAction: UIAlertAction = UIAlertAction(title: "Cancel", style: .Cancel) { action -> Void in
//cancel code
}
alertController.addAction(cancelAction)
let saveAction: UIAlertAction = UIAlertAction(title: "Save", style: .Default) { action -> Void in
let textField = alertController.textFields![0]
groceryItem.items.append(textField.text!)
self.tableView.reloadData()
}
alertController.addAction(saveAction)
//Add text field
// alertController.addTextFieldWithConfigurationHandler { (textField) -> Void in
// textField.textColor = UIColor.blackColor()
alertController.addTextFieldWithConfigurationHandler { (textField : UITextField!) -> Void in
textField.placeholder = "Enter an Item"
//alertController.textFields
}
//Present the AlertController
self.presentViewController(alertController, animated: true, completion: nil)
}
override func viewDidLoad() {
super.viewDidLoad()
//self.navigationItem.leftBarButtonItem = self.editButtonItem()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
// MARK: - Table view data source
override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
// #warning Incomplete implementation, return the number of sections
return 1
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
// #warning Incomplete implementation, return the number of rows
return groceryItem.items.count
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("groceryItem1", forIndexPath: indexPath)
cell.textLabel!.text = groceryItem.items [indexPath.row]
return cell
}
}
答案 0 :(得分:0)
如果您仔细查看班级groceryItem
的声明,您的购物清单中的每个项目都有static
个元素数组,因此每次添加新元素时,它都会在所有杂货项目中共享。
相反,您应该为每个杂货商品添加与其每个商品相关联的列表。
您可以定义一个新的struct
,为每个杂货项目保存其关联项目列表,如下所示:
struct GroceryItem {
var name: String
var items: [String]
}
我们将根据您的新模型更改GroceryListTableViewController
中的代码以重构代码,因此它应如下所示:
<强>
GroceryListTableViewController
强>:
class GroceryListTableViewController: UITableViewController, GroceryItemsTableViewControllerProtocol {
var groceryList = [GroceryItem]()
@IBAction func addButton(sender: UIBarButtonItem) {
let alertController: UIAlertController = UIAlertController(title: "Add Grocery Category", message: "", preferredStyle: .Alert)
//Cancel Button
let cancelAction: UIAlertAction = UIAlertAction(title: "Cancel", style: .Cancel) { action -> Void in
//cancel code
}
alertController.addAction(cancelAction)
let saveAction: UIAlertAction = UIAlertAction(title: "Save", style: .Default) { action -> Void in
let textField = alertController.textFields![0]
self.groceryList.append(GroceryItem(name: textField.text!, items: [String]()))
self.tableView.reloadData()
}
alertController.addAction(saveAction)
alertController.addTextFieldWithConfigurationHandler { (textField : UITextField!) -> Void in
textField.placeholder = "Enter an Item"
//alertController.textFields
}
//Present the AlertController
self.presentViewController(alertController, animated: true, completion: nil)
}
override func viewDidLoad() {
super.viewDidLoad()
//edit button
self.navigationItem.leftBarButtonItem = self.editButtonItem()
groceryList.append(GroceryItem(name: "Breakfast", items: ["Item1", "Item2", "Item3"]))
groceryList.append(GroceryItem(name: "Lunch", items: ["Item1", "Item2", "Item3"]))
groceryList.append(GroceryItem(name: "Dinner", items: ["Item1", "Item2", "Item3"]))
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return groceryList.count
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("prototype1", forIndexPath: indexPath) as UITableViewCell
cell.textLabel!.text = groceryList [indexPath.row].name
return cell
}
// pass a tableview cell value to navigationBar title in swift//
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
let destinationVC = segue.destinationViewController as! GroceryItemsTableViewController
let cell = sender as! UITableViewCell
let idx = self.tableView.indexPathForSelectedRow?.row
destinationVC.delegate = self
destinationVC.itemList = groceryList[idx!].items
destinationVC.navigationItem.title = cell.textLabel?.text
}
func didAddGroceryItem(itemName: String) {
let idx = self.tableView.indexPathForSelectedRow?.row
groceryList[idx!].items.append(itemName)
}
func didRemoveGroceryItem(index: Int) {
let idx = self.tableView.indexPathForSelectedRow?.row
groceryList[idx!].items.removeAtIndex(index)
}
}
在上面我已经重构了关于新模型的所有代码,我只把代码改变的地方保持不变。
您需要将与所选单元格相关联的项目传递给另一个UIViewController
,您可以在prepareForSegue
中轻松完成。为此,我们需要获取所选单元格的索引,并将元素传递给另一个UIViewController
,其中我们创建了一个新的[String]
数组作为数据源来显示项目。
代码中的另一个重点是GroceryListTableViewController
现在实现了一个名为GroceryItemsTableViewControllerProtocol
的新协议。这个协议是每次将新项目添加到列表时从GroceryListTableViewController
通知GroceryItemsTableViewController
的方式,称为委托模式。
<强>
GroceryItemsTableViewController
强>:
protocol GroceryItemsTableViewControllerProtocol: class {
func didAddGroceryItem(itemName: String)
func didRemoveGroceryItem(index: Int)
}
class GroceryItemsTableViewController: UITableViewController {
weak var delegate: GroceryItemsTableViewControllerProtocol?
var itemList: [String]!
@IBAction func addGroceryItemButtonPressed(sender: UIBarButtonItem) {
///new way///
let alertController: UIAlertController = UIAlertController(title: "Add Grocery Item", message: "", preferredStyle: .Alert)
//Cancel Button
let cancelAction: UIAlertAction = UIAlertAction(title: "Cancel", style: .Cancel) { action -> Void in
//cancel code
}
alertController.addAction(cancelAction)
let saveAction: UIAlertAction = UIAlertAction(title: "Save", style: .Default) { [weak self] action -> Void in
guard let s = self else { return }
let textField = alertController.textFields![0]
s.itemList.append(textField.text!)
s.delegate?.didAddGroceryItem(textField.text!)
s.tableView.reloadData()
}
alertController.addAction(saveAction)
alertController.addTextFieldWithConfigurationHandler { (textField : UITextField!) -> Void in
textField.placeholder = "Enter an Item"
//alertController.textFields
}
//Present the AlertController
self.presentViewController(alertController, animated: true, completion: nil)
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return itemList.count
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("groceryItem1", forIndexPath: indexPath)
cell.textLabel!.text = itemList[indexPath.row]
return cell
}
override func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
if editingStyle == .Delete {
// Delete the row from the data source
itemList.removeAtIndex(indexPath.row)
delegate?.didRemoveGroceryItem(indexPath.row)
tableView.deleteRowsAtIndexPaths([indexPath], withRowAnimation: .Fade)
} else if editingStyle == .Insert {
// Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view
}
}
}
修改强>
要正确处理删除,您应该创建一个新的委托方法,不要通知GroceryListTableViewController
项目已被删除,然后将其正确删除,您可以在上面的更新代码中看到。
我希望这对你有所帮助。