長進程，綁定更新和UI凍結

Question

我的WPF/C＃程序使用在特定序列中調用的不同方法。 每種方法都綁定到UI，在長時間處理後顯示一些數據。 我正在使用調度程序，導致被調用的方法在另一個線程中。 我也希望在不凍結UI的情況下執行此過程，例如可以取消過程並自由移動窗口。

我的問題是根本沒有更新用戶界面（進度條，計算步驟），取消按鈕在計算結束後纔會運行。 事實上，即使掛起的長期過程沒有完成，也不知道如何立即取消一般序列。

我不是100％肯定會使用正確的方式，有沒有人有更好的解決方案或任何建議？

ex。

public void CalculationCommand() 
    { 
     var bkw = new BackgroundWorker() 
     bkw.DoWork += Work; 
     bkw.RunWorkerAsync(Dispatcher.CurrentDispatcher); 
    } 

    public void Work(object sender, DoWorkEventArgs e) 
    { 
     var dispatcher = e.Argument as Dispatcher; 
     var dispatcherPriority = DispatcherPriority.Background; 
     Action action; 

     action =() => 
     { 
      UpdateStatut(StatutsInformation.Pending); 
     }; 
     dispatcher.BeginInvoke(action, dispatcherPriority); 

     ViewModel1 viewModel1 = null; 
     action =() => 
     { 
      UpdateProgress(10, "Sampling calculations"); 
      viewModel1 = Application.GetEchantillonnage();//Long process 
     }; 
     dispatcher.BeginInvoke(action, dispatcherPriority); 

     List<double> lengthList = null; 
     action =() => 
     { 
      UpdateProgress(20, "Length calculations"); 
      lengthList = AlgorithmLibrary.LengthCalculations(viewModel1);//Long process 
     }; 
     dispatcher.BeginInvoke(action, dispatcherPriority); 

     ViewModel2 viewModel2 = null; 
     action =() => 
     { 
      UpdateProgress(30, "Engine calculations"); 
      viewModel2 = Application.GetEngine();//Long process 
      AlgorithmLibrary.EngineCalculations(viewModel2);//Long process 
      var FilteredLength = AlgorithmLibrary.LengthFilter(lengthList);//Long process 
     };   dispatcher.BeginInvoke(action, dispatcherPriority); 

     ///... Others actions executed incrementing the progress value to 100% 

     action =() => 
     { 
      UpdateStatut(StatutsInformation.Finished); 
     }; 
     dispatcher.BeginInvoke(action, dispatcherPriority); 
    } 

private void UpdateStatut(StatutsInformation statutInformation) 
{ 
    ViewModelLoading.StatutInformation = statutInformation; 
} 

private void UpdateProgress(int value, string label) 
{ 
    ViewModelLoading.Progress = value; 
    ViewModelLoading.Step = label; 
} 

感謝

Answer 1

內Work你在後臺線程執行的方法。您每次撥打電話dispatcher.BeginInvoke時動作您傳遞給此方法將在上執行UI線程。看看你現在在做什麼？看看這段代碼再次

// Here, we are on a background thread 
action =() => 
{ 
    // This action is NOT executing yet! We are just defining it. 
    UpdateProgress(10, "Sampling calculations"); 
    // This is going to execute on the thread that executes this action! 
    viewModel1 = Application.GetEchantillonnage();//Long process 
}; 
// here, we are still on the background thread, but we are telling the 
// dispatcher to marshall the action onto the UI thread to execute it! 
dispatcher.BeginInvoke(action, dispatcherPriority); 

你做的UI線程上長時間運行的工作：/

的解決方案是容易的，但。簡單地拉出你的作品，並保留在後臺線程中。下面是相同的代碼，但按預期工作（除非在代碼中出現的其他問題）

action =() => UpdateProgress(10, "Sampling calculations");  
dispatcher.BeginInvoke(action, dispatcherPriority); 
viewModel1 = Application.GetEchantillonnage();//Long process 

Answer 2

你的代碼保持闖入後臺線程做UI線程上長時間運行的任務。 Dispatcher.BeginInvoke將委託編組回到UI線程。

試試這個：

private void RunOnUI(Action uiAction, DispatcherPriority dispatcherPriority = DispatcherPriority.Background) 
    { 
     dispatcher.BeginInvoke(uiAction, dispatcherPriority); 
    } 

    public void Work(object sender, DoWorkEventArgs e) 
    { 
     var dispatcher = e.Argument as Dispatcher; 
     var dispatcherPriority = DispatcherPriority.Background; 
     Action action; 

    runOnUI(() => 
    { 
     UpdateStatut(StatutsInformation.Pending); 
    }); 

    ViewModel1 viewModel1 = null; 
    RunOnUI(() => 
    { 
     UpdateProgress(10, "Sampling calculations"); 
    }); 
    viewModel1 = Application.GetEchantillonnage();//Long process 

    List<double> lengthList = null; 
    RunOnUI(() => 
    { 
     UpdateProgress(20, "Length calculations");    
    }); 
    lengthList = AlgorithmLibrary.LengthCalculations(viewModel1);//Long process   

    ViewModel2 viewModel2 = null; 
    RunOnUI(() => 
    { 
     UpdateProgress(30, "Engine calculations"); 
    }; 
     viewModel2 = Application.GetEngine();//Long process 
     AlgorithmLibrary.EngineCalculations(viewModel2);//Long process 
     var FilteredLength = AlgorithmLibrary.LengthFilter(lengthList);//Long process 

    ///... Others actions executed incrementing the progress value to 100% 

    RunOnUI(() => 
    { 
     UpdateStatut(StatutsInformation.Finished); 
    }); 
}