Ios 在领域数据库更改后重新加载TableView

我正在Swift中构建一个项目管理应用程序，使用Realm作为数据库来存储我的项目。

此WeekViewController

是我的初始视图控制器；它包含一个

UITableView

，以显示本周到期的项目。使用条形按钮，用户可以转到

AddProjectViewController

，顾名思义，它用于创建新项目并将它们保存到领域数据库<代码>添加项目视图控制器以模式显示

输入所需的项目详细信息后，用户可以单击“保存”按钮，将项目保存到领域数据库并取消视图，返回到

ThisWeekViewController

。但是，我在更新TableView以反映新项目的添加时遇到了问题

在查阅了Realm文档之后，我现在了解到，在Realm中，在数据库发生更改后，无需手动从TableView中添加或删除行。相反，您应该使用通知处理程序。但是，我不太确定在关闭

AddProjectViewController

后如何以及在何处合并它以重新加载我的TableView

在

ThisWeekViewController

的

视图中调用处理程序将出现

方法，因为视图实际上从未消失，因为

添加项目视图控制器

是以模式显示的

AddProjectViewController

：

class AddProjectViewController: FormViewController {
    
    // Realm Initialization
    let realm = try! Realm()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        self.navigationItem.rightBarButtonItem?.isEnabled = false
        
        form +++ Section()
            <<< TextRow(){ row in
                row.placeholder = "Postname"
                row.tag = "ProjectName"
            }.onChange({ (row) in
                if row.cell.textField.hasText {
                    self.navigationItem.rightBarButtonItem?.isEnabled = true
                } else {
                    self.navigationItem.rightBarButtonItem?.isEnabled = false
                }
            })
            <<< TextAreaRow() { row in
                row.placeholder = "Notizen"
                row.textAreaHeight = .fixed(cellHeight: 240.0)
                row.tag = "ProjectNotes"
            }
        
        form +++ Section()
            <<< DateTimeInlineRow() { row in
                row.title = "Fällig am"
                row.value = Date(timeIntervalSinceNow: 0)
                row.minuteInterval = 15
                row.tag = "ProjectDueDate"
        }
        
        navigationOptions = RowNavigationOptions.Enabled.union(.StopDisabledRow)
        animateScroll = true
        rowKeyboardSpacing = 20
    }
    
    // MARK: - User defined functions
    
    // If user presses the cancel button, the view is dismissed from screen.
    @IBAction func cancelButtonPressed(_ sender: UIBarButtonItem) {
        dismiss(animated: true) {}
    }
    
    // If user presses the save button, a new Project() item is created and saved to the Realm database.
    @IBAction func saveButtonPressed(_ sender: UIBarButtonItem) {
        
        // print(form.values())
        
        let newProject = Project()
        
        let titleRow: TextRow? = form.rowBy(tag: "ProjectName")
        let projectName = titleRow?.value
        newProject.title = projectName!
        
        let notesRow: TextAreaRow? = form.rowBy(tag: "ProjectNotes")
        let projectNotes = notesRow?.value
        newProject.notes = projectNotes
        
        let dueDateRow: DateTimeInlineRow? = form.rowBy(tag: "ProjectDueDate")
        let projectDueDate = dueDateRow?.value
        newProject.dueDate = projectDueDate
        
        newProject.dateCreated = NSDate.now
        
        print(newProject)
        

        // Save the new Project to the realm database
        do {
            try self.realm.write {
                realm.add(newProject)
            }
        }
        catch {
            print("Error saving item to Realm database. \(error)")
        }

        print(newProject)
        self.dismiss(animated: true)

    }
}

class ThisWeekViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {
    
    // MARK: - Variables
    
    @IBOutlet weak var thisWeekTableView: UITableView!
    
    // Realm initialization
    let realm = try! Realm()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        setupTableView()
        print(Realm.Configuration.defaultConfiguration.fileURL!)
    }
    
    // MARK: - Data Source / Delegate Methods
    
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return 7
    }
    
    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        //TODO: Handle user selection of a specific planned post
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        
        // Variables
        let thisWeekCell = thisWeekTableView.dequeueReusableCell(withIdentifier: ThisWeekTableViewCell.reuseIdentifier()) as! ThisWeekTableViewCell
        
        let today = Date()
        let day = Calendar.current.date(byAdding: .day, value: indexPath.row, to: today)
        let dayNumber = Calendar.current.component(.day, from: day!)

        let dateFormatter = DateFormatter()
        dateFormatter.dateFormat = "EEEE"
        let dayName = dateFormatter.string(from: day!)

        let startOfToday = Calendar.current.startOfDay(for: day!)
        let endOfToday = Calendar.current.date(byAdding: .second, value: 86399, to: startOfToday)!
        
        let projectNamesForCurrentDay = projectNamesForDay(startOfDay: startOfToday, endOfDay: endOfToday)
        
        thisWeekCell.setupProjectNameLabel(projectNames: projectNamesForCurrentDay)
        
        if indexPath.row == 0 {
            thisWeekCell.dayNumberLabel.textColor = UIColor.orange
            thisWeekCell.dayTextLabel.text = "Heute (\(dayName))"
        }

        if indexPath.row == 1 {
            thisWeekCell.dayTextLabel.text = "Morgen (\(dayName))"
        }

        if indexPath.row > 1 {
            thisWeekCell.dayTextLabel.text = dayName
        }

        thisWeekCell.dayNumberLabel.text = String(dayNumber)
        
        return thisWeekCell
        
    }
    
    // MARK: - User definded functions
    
    /**
     Initial setup for the TableView. Registers all neccessary custom cells, sets the delegate and dataSource, and enables AutoLayout.
     */
    func setupTableView() {
        thisWeekTableView.register(UINib(nibName: ThisWeekTableViewCell.nibName(), bundle: nil), forCellReuseIdentifier: ThisWeekTableViewCell.reuseIdentifier())
        thisWeekTableView.delegate = self
        thisWeekTableView.dataSource = self
        
        thisWeekTableView.rowHeight = UITableView.automaticDimension
        thisWeekTableView.estimatedRowHeight = 54.0
    }
    
    /**
     Takes two boundary objects of type Date and returns an array of strings containing the titles of all projects in the database that have a due date between the boundary dates.
     - Parameter startOfDay: The start-of-day boundary object
     - Parameter endOfDay: The end-of-day boundary object
     - Returns: An array of strings containing project titles
     */
    func projectNamesForDay(startOfDay: Date, endOfDay: Date) -> [String] {
        let filteredProjects = realm.objects(Project.self).filter("dueDate BETWEEN %@", [startOfDay, endOfDay])
        var projectNames = [String]()
        for project in filteredProjects {
            projectNames.append(project.title)
        }
        return projectNames
    }
    
}

---

每次项目结果更改时，应使用领域通知自动更新tableview：

// Observe Realm Notifications
let token = projectResult.observe { notification, realm in
    // reloadTableView
}

// later
token.invalidate()

---

每次项目结果更改时，应使用领域通知自动更新tableview：

// Observe Realm Notifications
let token = projectResult.observe { notification, realm in
    // reloadTableView
}

// later
token.invalidate()

---

我明白，我只是不确定这段代码应该放在我的ViewController中的什么地方。将其放在ViewDidLoad或ViewWillExample中不会产生预期的结果。我认为您应该将其放在ViewDidLoad中，并在项目结果更改时在回调中加载新数据+重新加载tableView，并在deinit（）中使令牌无效。我理解，我只是不确定这段代码应该放在我的ViewController中的何处。将其放置在ViewDidLoad或ViewWillExample中不会产生预期的结果。我认为您应该将其放置在ViewDidLoad中，并在项目结果更改时在回调中加载新数据+重新加载tableView，并在deinit（）中使令牌无效。