Closing a wpf window created on a different thread from the background worker WorkRunCompleted

Question

Hi there is a follow up to another question here

Here is the summary

In a wpf application in c# I had a long process of updating a remote database. to do this I created a background worker. However I wanted to have a window open and a progressbar run during the database update routine. All my attempts to achieve this on my main window with a progressbar set to Indeterminate failed as the "swishing" effect on my progressbar did not start to run on my main window till after my background worker thread had finished

Any with help and this article here I managed to open a new window in a different thread and run the background worker and have the progressbar "swish" properly and the background work run to completion. HOWEVER, my new question is

How do I close my progressbar window (called progressDialog) once my background work is finished?

Please bear in mind that I am quite new to this and code examples would be greatly apprieciated and I THINK, but I am not certain I am going to want to close the progressbar window from the background worker RunWorkerCompleted area of code

here is my code

I set up the background worker as

  public partial class MainWindow : Window
{
    //Declare background workers
    BackgroundWorker bwLoadCSV = new BackgroundWorker();


    //Declare class variables
    // some stuff

    public MainWindow()
    {
        InitializeComponent();
        //assign events to backgroundworkers
        bwLoadCSV.WorkerReportsProgress = true;
        bwLoadCSV.WorkerSupportsCancellation = true;
        bwLoadCSV.DoWork += new DoWorkEventHandler(bwLoadCSV_DoWork);
        bwLoadCSV.ProgressChanged += new ProgressChangedEventHandler(bwLoadCSV_ProgressChanged);
        bwLoadCSV.RunWorkerCompleted += new RunWorkerCompletedEventHandler(bwLoadCSV_RunWorkerCompleted);
      }
  }

I run the event on a button click event as;

private void CSV_Load_Click(object sender, RoutedEventArgs e)
    ///Function to read csv into datagrid
    ///
    {
        //Turn Cursor to wait
        System.Windows.Forms.Cursor.Current = System.Windows.Forms.Cursors.WaitCursor;
        Thread backgroundThread = new Thread(
    new ThreadStart(() =>
    {
        ProgressDialog progressDialog = new ProgressDialog();
        progressDialog.tbEvent.Text = "Loading CSV Data....";
        progressDialog.progressBar1.IsIndeterminate = true;
        progressDialog.ShowDialog();
    }

));
        backgroundThread.SetApartmentState(ApartmentState.STA);
        backgroundThread.Start();

        //Test connection to sql server
        if (CHHoursDataProvider.IsDatabaseOnline() == false)
        {
            System.Windows.Forms.MessageBox.Show("Can not establish contact with sql server" + "\n" + "Contact IT", "Connection Error");
            //Set UI picture
            return;
        }
        //Set a control to update the user here
        tbLoadDgStat.Visibility = Visibility.Visible;

        //tbLoadDgStat.Text = "Getting data templete from Database...";
        string FilePath = txFilePath.Text;
        if (bwLoadCSV.IsBusy != true)
        {
            //load the context object with parameters for Background worker
            bwCSVLoadContext Context = new bwCSVLoadContext();
            Context.Site = cBChSite.Text;
            Context.FilePath = txFilePath.Text;
            Context.FileName = fileTest;
            Context.Wageyear = cbWageYear.Text;
            Context.Startdate = ((DateTime)dpStartDate.SelectedDate);
            Context.Enddate = ((DateTime)dpEndDate.SelectedDate);

            bwLoadCSV.RunWorkerAsync(Context);                
         }
    }

My progressbar form progressDialog xaml and class are this;

<Window x:Class="Test_Read_CSV.ProgressDialog"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="Progress Dialog" Height="115" Width="306" Name="ProgressPopup">
<Grid>
    <ProgressBar Height="31" HorizontalAlignment="Left" Margin="12,33,0,0" Name="progressBar1" VerticalAlignment="Top" Width="250" x:FieldModifier="public" />
    <TextBox Height="23" HorizontalAlignment="Left" Margin="7,4,0,0" Name="tbEvent" VerticalAlignment="Top" Width="254" IsReadOnly="True" IsEnabled="False" x:FieldModifier="public" />
</Grid>

class is
 public partial class ProgressDialog : Window
{
    public ProgressDialog()
    {
        WindowStartupLocation = WindowStartupLocation.CenterScreen;
        InitializeComponent();
        progressBar1.IsIndeterminate = true;

    }

My background worker completed code is

  private void bwLoadCSV_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
    {
        bwCSVLoadContext Context = e.Result as bwCSVLoadContext;
        Thread.Sleep(5000);
        if ((e.Cancelled == true))
        {

            this.tbLoadDgStat.Text = "Canceled!";
            System.Threading.Thread.Sleep(1000);

            System.Windows.Forms.Cursor.Current = System.Windows.Forms.Cursors.Default;
            tbLoadDgStat.Visibility = Visibility.Hidden;
        }

        else if (!(e.Error == null))
        {
            //this.tbProgress.Text = ("Error: " + e.Error.Message);

        }

        else
        {
            if (Context.LoadResult == true)
            {
                this.dgCSVData.DataContext = oTable.DefaultView;
                btUpload.IsEnabled = true;
            }

            **//close the progressbar window some how here!!!**


            //On the main window
            this.tbLoadDgStat.Text = "Complete";
            progressBar1.Value = 100;


            System.Windows.Forms.Cursor.Current = System.Windows.Forms.Cursors.Default;
            tbLoadDgStat.Visibility = Visibility.Hidden;
        }



        System.Windows.Forms.Cursor.Current = System.Windows.Forms.Cursors.Default;

    }

If you are using .NET 4.5, it will be much easier to use Async and Await and Tasks with Progress / Cancellation Tokens. The links should be helpful for getting up to speed. I find they make it easier to avoid cross threading issues too. [1]: http://msdn.microsoft.com/en-us/library/vstudio/hh191443.aspx [2]: http://blogs.msdn.com/b/dotnet/archive/2012/06/06/async-in-4-5-enabling-progress-and-cancellation-in-async-apis.aspx — JsAndDotNet, Oct 14 '13 at 15:51
Unfortunately; it is .Net 4.0, but I will take a look thank-you — Ian W, Oct 14 '13 at 16:33
@HockeyJ do you think that Async CTP is an option for me here? — Ian W, Oct 14 '13 at 16:51
I have used both methods in production environments and find the mix of Async and Tasks far easier to work with than old style threads & background workers. Haven't found a case for going back to the old way yet. — JsAndDotNet, Oct 15 '13 at 07:44

paparazzo · Accepted Answer · 2013-10-14T18:17:27.517

Do the Background in the progress page
If you need to pass (and return) an object then do so in the Progress ctor

private void click(object sender, RoutedEventArgs e)
{
    Progress progressDialog = new Progress();
    progressDialog.Show();
    if (progressDialog != null) progressDialog = null;
}

namespace BackGroundWorkerShowDialog
{
    /// <summary>
    /// Interaction logic for Progress.xaml
    /// </summary>
    public partial class Progress : Window
    {
        BackgroundWorker bwLoadCSV = new BackgroundWorker();
        public Progress()
        {
            InitializeComponent();
            //assign events to backgroundworkers
            bwLoadCSV.WorkerReportsProgress = true;
            bwLoadCSV.WorkerSupportsCancellation = true;
            bwLoadCSV.DoWork += new DoWorkEventHandler(backgroundWorker1_DoWork);
            bwLoadCSV.ProgressChanged += new ProgressChangedEventHandler(backgroundWorker1_ProgressChanged);
            bwLoadCSV.RunWorkerCompleted += new RunWorkerCompletedEventHandler(backgroundWorker1_RunWorkerCompleted);
            if (bwLoadCSV.IsBusy != true)
            {
                // Start the asynchronous operation.
                bwLoadCSV.RunWorkerAsync();
            }

        }

        private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
        {
            BackgroundWorker worker = sender as BackgroundWorker;
            for (int i = 1; i <= 10; i++)
            {
                if (worker.CancellationPending == true)
                {
                    e.Cancel = true;
                    break;
                }
                else
                {
                    // Perform a time consuming operation and report progress.
                    System.Threading.Thread.Sleep(500);
                    worker.ReportProgress(i * 10);
                }
            }
        }

        private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
        {

            if (e.Cancelled == true)
            {
                //resultLabel.Text = "Canceled!";
            }
            else if (e.Error != null)
            {
                //resultLabel.Text = "Error: " + e.Error.Message;
            }
            else
            {
                //resultLabel.Text = "Done: " + e.Error.Message;
            }
            this.Close();
        }

        private void backgroundWorker1_ProgressChanged(object sender,
            ProgressChangedEventArgs e)
        {
            this.tbProgress.Text = e.ProgressPercentage.ToString();
        }
    }

}

hi @Blam unfornately I get the exception "Error 1 the name 'progressDialog' does not exist in the current context" When this is put into the bwLoadCSV_RunworkerCompleted — Ian W, Oct 14 '13 at 16:32
I tested and got an error on the ThreadStart. I will delete once you have an accepted answer. — paparazzo, Oct 14 '13 at 17:14
Hi @Blam I sort this issue out the problem was dealt with with a delegate as you said I just had to play around where my call back went — Ian W, Oct 25 '13 at 10:12

Closing a wpf window created on a different thread from the background worker WorkRunCompleted

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