关于WPF进度条的使用

本文讲述如何在软件启动和窗体按钮操作时弹出进度条。

运行环境：Win10、VS2022

一、新建WPF项目。

二、新建WPF窗体。

1、新建窗体，取名DefProcessBar.xaml。

 2、设置窗体属性、样式。

<Window x:Class="WpfApp4.DefProcessBar"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp4"
        mc:Ignorable="d"
        Title="DefProcessBar" Width="300" Height="50"
        WindowStartupLocation="CenterScreen"
        WindowStyle="None" AllowsTransparency="True" Background="Transparent" ShowInTaskbar="False" ResizeMode="NoResize">

2.1、WindowStartupLocation="CenterScreen"是窗体在屏幕中间显示；

2.2、WindowStyle="None"是不要窗体顶部内容；

2.3、AllowsTransparency="True"是允许窗体透明；

2.4、Background="Transparent"是设置透明背景；

2.5、ShowInTaskbar="False"是指示此窗口是否出现在任务栏；

2.6、ResizeMode="NoResize"是不可调节窗体大小。

 3、添加进度消息和进度条。

<Grid.RowDefinitions>
    <RowDefinition Height="25"></RowDefinition>
    <RowDefinition Height="25"></RowDefinition>
</Grid.RowDefinitions>

<TextBlock Grid.Row="0" Name="txtTitle" FontSize="16" Foreground="Yellow" HorizontalAlignment="Left" TextWrapping="Wrap" Margin="10, 0,0,0"></TextBlock>
<ProgressBar Grid.Row="1" x:Name="progressBar" Maximum="100" Height="25" Width="300" Foreground="Green" Background="LightGray" HorizontalContentAlignment="Center" VerticalContentAlignment="Center"/>

 4、添加DefProcessBar.xaml.cs代码

/// <summary>
/// DefProcessBar.xaml 的交互逻辑
/// </summary>
public partial class DefProcessBar : Window
{
    public DefProcessBar()
    {
        InitializeComponent();
    }

    public void ShowProcess(int process, string title = "")
    {
        progressBar.Dispatcher.Invoke(() =>
        {
            this.txtTitle.Text = title;
            this.progressBar.Value = process;
        });
    }

    public void SetProcess(DefProcessBar defProcessBar, int process, string title = "")
    {
        if (process > 100)
        {
            process = 100;
        }
        else if (process < 0)
        {
            process = 0;
        }
        title += $" ({process}%)";
        defProcessBar.ShowProcess(process, title);
    }
}

三、在App.xaml.cs中使用

/// <summary>
/// App.xaml 的交互逻辑
/// </summary>
public partial class App : Application
{
    protected override void OnStartup(StartupEventArgs e)
    {
        Application.Current.ShutdownMode = System.Windows.ShutdownMode.OnExplicitShutdown;

        bool isFinish = false;

        //DialogWait defProcessBar = new DialogWait();
        DefProcessBar defProcessBar = new DefProcessBar();
        Task.Run(() =>
        {
            defProcessBar.SetProcess(defProcessBar, 20, "启动中，请稍后...");
　　　　　　  // 写入实际处理代码
            Thread.Sleep(500);
            defProcessBar.SetProcess(defProcessBar, 40, "启动中，请稍后...");
            Thread.Sleep(500);
            defProcessBar.SetProcess(defProcessBar, 60, "启动中，请稍后...");
            Thread.Sleep(500);
            defProcessBar.SetProcess(defProcessBar, 80, "启动中，请稍后...");
            Thread.Sleep(500);

            defProcessBar.Dispatcher.Invoke(() =>
            {
                defProcessBar.Close();
            });
        });
        defProcessBar.ShowDialog();

        if (isFinish)
        {
            base.OnStartup(e);
            Application.Current.ShutdownMode = ShutdownMode.OnMainWindowClose;
        }
        else
        {
            this.Shutdown();
        }
    }
}

启动软件查看效果。

四、在主窗体MainWindow中弹出进度条。

1、添加按钮。

 2、添加按钮事件处理。

 private void Button_Click(object sender, RoutedEventArgs e)
 {
     DefProcessBar defProcessBar = new DefProcessBar();
     Task.Run(() =>
     {
         defProcessBar.SetProcess(defProcessBar, 20, "启动中，请稍后...");
         Thread.Sleep(500);
         defProcessBar.SetProcess(defProcessBar, 40, "启动中，请稍后...");
         Thread.Sleep(500);
         defProcessBar.SetProcess(defProcessBar, 60, "启动中，请稍后...");
         Thread.Sleep(500);
         defProcessBar.SetProcess(defProcessBar, 80, "启动中，请稍后...");
　　　　  //写入实际处理代码
         Thread.Sleep(500);

         defProcessBar.Dispatcher.Invoke(() =>
         {
             defProcessBar.Close();
         });
     });
     defProcessBar.ShowDialog();
 }

3、效果跟软件启动时一样。

缺点：所有逻辑必须放到异步处理。