如何在进行中对话框中正确调用后台线程

Question

应用程序的主窗口打开一个正在进行的对话框，该对话框应调用后台线程。对话框应该出现，直到线程完成：

var dialog = new WorkInProgressDialog();
dialog = ShowDialg;

现在的问题是在哪里/如何调用WorkInProgressDialog构造函数中的线程？如果在构造函数中调用它，那么在线程完成之前，对话框将不可见。

此外，该对话框应在线程完成后自动关闭。

Answer 1

以下是一个有望对您有所帮助的示例。WorkInProgressDialog:的一些简单标记

<Window x:Class="WorkInProgressExample.WorkInProgressDialog"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="WorkInProgressDialog" Height="100" Width="300" WindowStyle="None" 
    ResizeMode="NoResize" WindowStartupLocation="CenterScreen">
    <Border BorderThickness="3" CornerRadius="5" BorderBrush="Black" Padding="10">
        <Grid>
            <Grid.RowDefinitions>
                <RowDefinition Height="*"></RowDefinition>
                <RowDefinition Height="Auto"></RowDefinition>
                <RowDefinition Height="Auto"></RowDefinition>
                <RowDefinition Height="*"></RowDefinition>
            </Grid.RowDefinitions>            
            <TextBlock Grid.Row="1" Name="WorkProgressTextBlock">Work in progress...</TextBlock>
            <ProgressBar Grid.Row="2" Height="30" Name="WorkProgressBar"></ProgressBar>
        </Grid>
    </Border>
</Window>

然后在后面的代码中：

private bool _closeAuthorised = false;
public WorkInProgressDialog()
{
    InitializeComponent();
    WorkProgressBar.Maximum = 10;
    WorkProgressBar.Minimum = 0;
    Task.Factory.StartNew(() =>
    {
        // Do whatever processing you need to here
        for (int i = 0; i < 10; i++)
        {
            // Any updates to the UI need to be done on the UI thread
            this.Dispatcher.Invoke((Action)(() =>
            {
                WorkProgressBar.Value = i;
            }));
            Thread.Sleep(1000);
        }
        // Set the DialogResult and hence close, also on the UI thread
        this.Dispatcher.Invoke((Action)(() =>
        {
            _closeAuthorised = true;
            this.DialogResult = true;
        }));
    });
}
protected override void OnClosing(System.ComponentModel.CancelEventArgs e)
{
    // If the user uses ALT+F4 to try andclose the loading dialog, this will cancel it
    if (!_closeAuthorised)
        e.Cancel = true;
    base.OnClosing(e);
}

然后你想在哪里使用它：

var dialog = new WorkInProgressDialog();
bool? result = dialog.ShowDialog();