显示加载窗口

我在WPF中的应用程序加载外部资源，所以我想在程序加载时显示加载表单。

我尝试创建表单，并在加载代码之前显示，并在加载结束时关闭。

private void Window_Loaded(object sender, RoutedEventArgs e) { LoadForm lf = new LoadForm(); lf.Visibility = Visibility.Visible; // Al code that delays application loading lf.Close(); } 

但我唯一得到的是表单在加载进度完成并立即关闭时显示。

我认为我需要使用System.Threading但不确定。

谢谢。

注意我在Window_Loaded（）方法中加载所有应用程序外部资源，而不是在主类方法中。

Answer 1

您应该查看这篇关于在WPF中创建SplashScreen的 MSDN文章。 基本上，您将要显示的图像添加到项目中，并将Build Action设置为SplashScreen，它将在程序启动时显示，并在显示主应用程序窗口时消失。

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您还可以尝试导入System.ComponentModel类并使用BackgroundWorker显示您的加载表单，它将允许您保留UI的响应性。

 public partial class MainWindow : Window { Window1 splash; BackgroundWorker bg; public MainWindow() { InitializeComponent(); bg = new BackgroundWorker(); bg.DoWork += new DoWorkEventHandler(bg_DoWork); bg.RunWorkerCompleted += new RunWorkerCompletedEventHandler(bg_RunWorkerCompleted); } void bg_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e) { splash.Hide(); } void bg_DoWork(object sender, DoWorkEventArgs e) { System.Threading.Thread.Sleep(10000); } private void Window_Loaded(object sender, RoutedEventArgs e) { splash = new Window1(); splash.Show(); bg.RunWorkerAsync(); } } 

Answer 2

您应该将耗费时间的代码放在后台线程中（为此您可以使用BackgroundWorker，Task或Async Await，具体取决于您的dot net framework版本）

 private void Window_Loaded(object sender, RoutedEventArgs e) { LoadForm lf = new LoadForm(); lf.Visibility = Visibility.Visible; //start the time consuming task in another thread } HeavyTaskCompleteEvent() { lf.Close(); } 

另外，请注意显示加载屏幕的最佳方式。 您也可以在主窗口中显示一些动画。 我不认为展示表格是最好的方式。

Answer 3

我前一段时间做过Loader课程你可以使用。 它在执行加载方法时显示一个窗口，在完成时关闭它并为您提供方法的输出：

 public class Loader:FrameworkElement { private Func _execute; public TActionResult Result { get; private set; } public delegate void OnJobFinished(object sender, TActionResult result); public event OnJobFinished JobFinished; public Loader(Func execute) { if (execute == null) throw new ArgumentNullException("execute"); _execute = execute; } private Window GetWaitWindow() { Window waitWindow = new Window { Height = 100, Width = 200, WindowStartupLocation = WindowStartupLocation.CenterScreen, WindowStyle = WindowStyle.None }; waitWindow.Content = new TextBlock { Text = "Please Wait", FontSize = 30, FontWeight = FontWeights.Bold, HorizontalAlignment = HorizontalAlignment.Center, VerticalAlignment = VerticalAlignment.Center }; return waitWindow; } public void Load(Window waitWindow = null) { if (waitWindow == null) { waitWindow = GetWaitWindow(); } BackgroundWorker worker = new BackgroundWorker(); worker.DoWork += delegate { Dispatcher.BeginInvoke(new Action(delegate { waitWindow.ShowDialog(); })); Result = _execute(); Dispatcher.BeginInvoke(new Action(delegate() { waitWindow.Close(); })); }; worker.RunWorkerCompleted += delegate { worker.Dispose(); if (JobFinished != null) { JobFinished(this, Result); } }; worker.RunWorkerAsync(); } } 

如何使用它：

 Loader loader = new Loader(MethodName); loader.JobFinished += new Loader.OnJobFinished(loader_JobFinished); loader.Load(); void loader_JobFinished(object sender, TResult result) { // do whatever you want with your result here }