如何在WPF中更新DataGrid中的進度條？

我是 .Net 的新手，我想知道當我單擊 DataGrid 上特定行中的下載按鈕時如何更新進度條。由于解決這個問題的資源有限，我不明白如何實作這一點。

 <DataGrid AutoGenerateColumns="False" x:Name="servers" HorizontalAlignment="Center" Height="148" Margin="0,78,0,0" VerticalAlignment="Top" Width="772" PreviewMouseDoubleClick="clientPreview" >
        <DataGrid.Columns>
            <DataGridTextColumn Header="ID" IsReadOnly="True" Binding="{Binding Id}" Width="50"></DataGridTextColumn>
            <DataGridTemplateColumn Header="Progress" 
                                    Width="100">
                <DataGridTemplateColumn.CellTemplate>
                    <DataTemplate>
                        <ProgressBar 
                            Value="{Binding Progress}"
                            Minimum="0" Maximum="100" />
                    </DataTemplate>
                </DataGridTemplateColumn.CellTemplate>
            </DataGridTemplateColumn>
            <DataGridTemplateColumn Header="Action" Width="100">
                <DataGridTemplateColumn.CellTemplate>
                    <DataTemplate >
                        <Button  Background="#FF00FF35" Click="beginDownload">Download</Button>
                    </DataTemplate>
                </DataGridTemplateColumn.CellTemplate>
            </DataGridTemplateColumn>
        </DataGrid.Columns>
    </DataGrid>

生成的 DataGrid 如下所示：

BeginDownload 方法如下所示：

private void beginDownload(object sender, RoutedEventArgs e)
    {
        Clients selected = servers.SelectedItem as Clients;
        if (selected != null)
        {
            if (selected.Id == 0)
            {
                MessageBox.Show("Selected Feild is Empty", Title = "Empty Feild Selected");
            }
            else
            {
                //Update Progess Bar and Other Methods

            }
        }
        else
        {
            MessageBox.Show("Selected Field is Empty", Title = "Empty Field Selected");
        }
    }

我只想知道如何更新特定行中的進度條。例如，如果我放置一個 for 回圈并將進度從 0 更新到 100。如何將整數值系結到進度條？

發現沒有答案的類似問題 -單擊時同一行中的 Wpf Datagrid 更改元素

uj5u.com熱心網友回復：

在 WPF 中非常流行的帶有命令模式的MVVM方法。據此..您需要擁有View和ViewModel ..然后您將能夠使用網格中的“下載”按鈕的命令并將引數傳遞給它。

public class ClientsViewModel : INotifyPropertyChanged
{  
   public DelegateCommand DownloadCommand {get; private set;}

   // ctor
   public ClientsVM() 
   {
        DownloadCommand  = new DelegateCommand(DownloadExecute));
   }

   // async method allow to not block UI thread 
   public async void DownloadExecute(object param)
   {
       var client = param as Clients;
       if (client==null) return;

       // TODO: call real code for download 
       for (int i=0; i<100; i  )
       {
          await Task.Delay(100); // slow changes of progress
          client.Progress = i;   // if setter of Progress raised NotifyPropertyChanged.. it will update ProgressBar in your DataGrid
       }      
   }
}

要使用您的 DownloadCommand，只需將其系結到 Button 的屬性

<DataGrid AutoGenerateColumns="False" x:Name="servers" HorizontalAlignment="Center" Height="148" Margin="0,78,0,0" VerticalAlignment="Top" Width="772" PreviewMouseDoubleClick="clientPreview">
        <DataGrid.Columns>
            <DataGridTextColumn Header="ID" IsReadOnly="True" Binding="{Binding Id}" Width="50"></DataGridTextColumn>
            <DataGridTemplateColumn Header="Progress" 
                                    Width="100">
                <DataGridTemplateColumn.CellTemplate>
                    <DataTemplate>
                        <ProgressBar 
                            Value="{Binding Progress}"
                            Minimum="0" Maximum="100" />
                    </DataTemplate>
                </DataGridTemplateColumn.CellTemplate>
            </DataGridTemplateColumn>
            <DataGridTemplateColumn Header="Action" Width="100">
                <DataGridTemplateColumn.CellTemplate>
                    <DataTemplate >
                        <Button  Background="#FF00FF35" Command="{Binding DownloadCommand, Mode=OneWay}" CommandParameter="{Binding}">Download</Button>
                    </DataTemplate>
                </DataGridTemplateColumn.CellTemplate>
            </DataGridTemplateColumn>
        </DataGrid.Columns>
    </DataGrid>

uj5u.com熱心網友回復：

我在 Page.xaml.cs 中的解決方案：

Visual vis;
private void beginDownload(object sender, RoutedEventArgs e)
{
    Clients selected = servers.SelectedItem as Clients;
    if (selected != null)
    {
        if (selected.Id == 0)
        {
            MessageBox.Show("Selected Feild is Empty", Title = "Empty Feild Selected");
        }
        else
        {
            for (vis = sender as Visual; vis != null; vis = VisualTreeHelper.GetParent(vis) as Visual)
                    if (vis is DataGridRow) //Find current DataGridRow
                    {
                        ProgressChanged();
                        //Other methods
                        break;
                    }
        }
    }
    else
    {
        MessageBox.Show("Selected Field is Empty", Title = "Empty Field Selected");
    }
}
private void ProgressChanged()
    {
        // Update the progressbar percentage 
        for (int i = 0; i <= 100; i  )
        {
            ((Clients)(((DataGridRow)vis).Item)).Progress = i;
        }
    }

我的客戶類：

public class Clients : INotifyPropertyChanged
{
    private int mProgress;
    public Clients()
    {
        Id = 0;
    }

    public int Id { get; set; }

    public int Progress
    {
        get { return mProgress; }
        set
        {
            mProgress = value;
            OnPropertyChanged("Progress");
        }
    }

    private void OnPropertyChanged(string propertyName)
    {
        if (PropertyChanged != null)
        {
            PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
        }
    }

    public event PropertyChangedEventHandler PropertyChanged;
}

我還有一個問題我的進度條速度太快了，我怎樣才能減慢進度條的速度？

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