如何在 c# wpf 窗口中一个接一个地显示标签集

Question

我有一个wpf窗口，它有四个标签m1，m2，m3，m4。当我单击窗口中的按钮时，所有四个标签应该一个接一个地显示。但是我立即显示所有标签，这不应该发生。

private void button_Click(object sender, RoutedEventArgs e)
{
m1.Content = DateTime.Now.ToString("HH:mm:ss") + "      Establishing Connection";
//some code
m2.Content = DateTime.Now.ToString("HH:mm:ss") + "      Connected";
//some code
m3.Content = DateTime.Now.ToString("HH:mm:ss") + "      Processing";
//some code
m4.Content = DateTime.Now.ToString("HH:mm:ss") + "      Finished";
}

运行应用程序后，窗口显示以下所有标签，而不是一次显示，而不是根据时间一个接一个地显示

10：

14：20 建立连接

10：

14：24 已连接

10：

14：26 处理

10：

14：30 完成

Answer 1

您正在寻找的容器称为 StackPanel，它会自动将任何元素一个接一个地放入其中。

例

<StackPanel Orientation="Vertical">
            <Label Name="m1"/>
            <Label Name="m2"/>
            <Label Name="m3"/>
            <Label Name="m4"/>
</StackPanel>

Answer 2

您可以

做的是在设置Label的Content后，您可以切换Label的Visibility，这样您就不会一次获得所有Label，而是一一获得它。正如@Dan建议的那样，使用StackPanel来安排Label。还要注意一个要点，即每次操作后都会更新 UI 线程。

下面是我使用的示例代码。

MainWindow.xaml

<StackPanel>
    <Button Content="Testing" Click="Button_Click" />
    <Label Name="m1" Visibility="Hidden" />
    <Label Name="m2" Visibility="Hidden" />
    <Label Name="m3" Visibility="Hidden" />
    <Label Name="m4" Visibility="Hidden" />
</StackPanel>

MainWindow.xaml.cs

public partial class MainWindow : Window
{
    public MainWindow ()
    {
        InitializeComponent ();
    }
    private async void Button_Click (object sender, RoutedEventArgs e)
    {
        m1.Content = DateTime.Now.ToString ("HH:mm:ss") + "      Establishing Connection";
        m1.Visibility = Visibility.Visible;
        await Task.Run (() => Thread.Sleep (2000));
        m2.Content = DateTime.Now.ToString ("HH:mm:ss") + "      Connected";
        m2.Visibility = Visibility.Visible;
        await Task.Run (() => Thread.Sleep (2000));
        m3.Content = DateTime.Now.ToString ("HH:mm:ss") + "      Processing";
        m3.Visibility = Visibility.Visible;
        await Task.Run (() => Thread.Sleep (2000));
        m4.Content = DateTime.Now.ToString ("HH:mm:ss") + "      Finished";
        m4.Visibility = Visibility.Visible;
        await Task.Run (() => Thread.Sleep (2000));
    }
}

我希望它有所帮助。还可以使用BackgroundWorker来避免 UI 冻结。

下面是使用BackgroundWorker的代码

MainWindow.xaml.cs

public partial class MainWindow : Window
{
    private readonly BackgroundWorker worker = new BackgroundWorker();
    public MainWindow()
    {
        InitializeComponent();
    }
    private void Button_Click(object sender, RoutedEventArgs e)
    {
        worker.DoWork += worker_DoWork;
        worker.RunWorkerCompleted += worker_RunWorkerCompleted;
        worker.RunWorkerAsync();
    }
    void worker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
    {
        m1.Visibility = Visibility.Hidden;
        m2.Visibility = Visibility.Hidden;
        m3.Visibility = Visibility.Hidden;
        m4.Visibility = Visibility.Hidden;
    }
    void worker_DoWork(object sender, DoWorkEventArgs e)
    {
        Dispatcher.Invoke(() =>
        {
            m1.Content = DateTime.Now.ToString("HH:mm:ss") + "      Establishing Connection";
            m1.Visibility = Visibility.Visible;
        });
        Thread.Sleep(2000);//your code
        Dispatcher.Invoke(() =>
        {
            m2.Content = DateTime.Now.ToString("HH:mm:ss") + "      Connected";
            m2.Visibility = Visibility.Visible;
        });
        Thread.Sleep(2000);//your code
        Dispatcher.Invoke(() =>
        {
            m3.Content = DateTime.Now.ToString("HH:mm:ss") + "      Processing";
            m3.Visibility = Visibility.Visible;
        });
        Thread.Sleep(2000);//your code
        Dispatcher.Invoke(() =>
        {
            m4.Content = DateTime.Now.ToString("HH:mm:ss") + "      Finished";
            m4.Visibility = Visibility.Visible;
        });
        Thread.Sleep(2000);//your code
    }
}