Question

任何人都知道如何添加到另一个类的一个类中的ObservableCollection？我要做的是当您点击CurrentTasks页面上的按钮时，它会在我CurrentTask班级的completedTaskList中添加新的CompletedTasks

当前任务页面

public partial class CurrentTasks : ContentPage
{
    private ObservableCollection<Models.CurrentTask> currentTaskList { get; set; }
    internal ObservableCollection<Models.CurrentTask> CurrentTasklist { get => currentTaskList; set => currentTaskList = value; }
    public CurrentTasks()
    {
        currentTaskList = new ObservableCollection<Models.CurrentTask>()
        {
            new Models.CurrentTask {TaskName = "First Task", TaskDescription = "Very important", Prioity = ImageSource.FromResource("LifeManager.Images.high.png")},
            new Models.CurrentTask {TaskName = "Second Task", TaskDescription = "Not as important", Prioity = ImageSource.FromResource("LifeManager.Images.low.png")}
        };
        InitializeComponent();
        listView.ItemsSource = currentTaskList;
    }

    private void Button_Clicked(object sender, EventArgs e)
    {
        CurrentTask newtask = new CurrentTask { TaskName = "New task", TaskDescription = "New task Descroipti", Prioity = ImageSource.FromResource("LifeManager.Images.high.png") };
        currentTaskList.Add(newtask);
    }
}

已完成的任务

public partial class CompletedTasks 
{
    private ObservableCollection<Models.CurrentTask> completedTaskList { get; set; }
    internal ObservableCollection<Models.CurrentTask> CompletedTaskList { get => CompletedTaskList; set => CompletedTaskList = value; }
    public CompletedTasks()
    {
        InitializeComponent();          
        completedTaskList = new ObservableCollection<Models.CurrentTask>()
        {
            new Models.CurrentTask {TaskName = "First Task", TaskDescription = "Very important", Prioity = ImageSource.FromResource("LifeManager.Images.high.png")},
            new Models.CurrentTask {TaskName = "Second Task", TaskDescription = "Not as important", Prioity = ImageSource.FromResource("LifeManager.Images.low.png")}
        };

        listView.ItemsSource = completedTaskList;
    }

    private void Button_Clicked(object sender, EventArgs e)
    {
        CurrentTask newtask = new CurrentTask { TaskName = "New task", TaskDescription = "New task Descroipti", Prioity = ImageSource.FromResource("LifeManager.Images.high.png") };
    }
}

Answer 1

我假设CompletedTasks对象在其他窗口中维护。下面的例子我假设为mainWindow。

在主窗口中，您可以维护CompletedTasks的对象

并具有返回对象的属性。

public partial class MainWindow : Window
{
        private CompletedTasks comT;

        public CompletedTasks completedTask
        {
            get { return comT; }
            set { comT = value; }
        }
..
..
..
..

}

现在在您的页面中，访问主窗口并更新列表。

如下所示。

public partial class CurrentTasks : ContentPage
{

....
....
....
....

    private void Button_Clicked(object sender, EventArgs e)
    {
        CurrentTask newtask = new CurrentTask { TaskName = "New task", TaskDescription = "New task Descroipti", Prioity = ImageSource.FromResource("LifeManager.Images.high.png") };
        currentTaskList.Add(newtask);


       //update Here when task is done
       //Access the main window
       var mainWin = Application.Current.Windows
                .Cast<Window>()
                .FirstOrDefault(window => window is MainWindow) as MainWindow;

        mainWin.completedTask.CompletedTaskList.Add(newtask);
    }
}

例如我使用了Main Window。你可以使用任何窗口。

如何添加到另一个页面中的集合？

1 个答案: