Task dalay

[grizoood]

Hello

I'm trying to add a 1sec delay between each instance insertion but I'm having a problem, my transaction is rollback.

public ICommand InsertCommand
        {
            get
            {
                return _insertCommand ?? (_insertCommand = new RelayCommand(
                   async (obj) =>
                   {
                       await RevitTask.RunAsync(
                            async app =>
                            {
                                try
                                {
                                    var document = app.ActiveUIDocument.Document;

                                    using (Transaction transaction = new Transaction(document))
                                    {
                                        transaction.Start("Insert");

                                        int count = 20;

                                        for (int i = 0; i < count; i++)
                                        {
                                            string family_2d = "Family";
                                            string symbol_2d = "Symbol";

                                            var symbol = document.FindSymbol(family_2d, symbol_2d);

                                            FamilyInstance instance = document.Create.NewFamilyInstance(new XYZ(0, 0, 0), symbol, StructuralType.NonStructural);

                                            await Task.Delay(1000);

                                            Informations = $"Insert {i + 1}/{count}";
                                        }

                                        transaction.Commit();
                                    }

                                    Informations = "Finished";
                                }
                                catch (Exception ex)
                                {

                                }
                            });
                   },
                    (obj) =>
                    {
                        return obj as Window != null;
                    }));
            }
        }

[KennanChan]

try to dispose the transaction manually rather than relying on the "using" statement.

[KennanChan]

Or you can create a transaction in every loop

[grizoood]

On the second pass through the loop I get this exception :

 await RevitTask.RunAsync(
                            async app =>
                            {
                                try
                                {
                                    var document = app.ActiveUIDocument.Document;

                                    int count = 20;

                                    for (int i = 0; i < count; i++)
                                    {
                                        string family_2d = "Family";
                                        string symbol_2d = "Symbol";

                                        using (Transaction transaction = new Transaction(document))
                                        {
                                            transaction.Start("Insert");

                                            var symbol = document.FindSymbol(family_2d, symbol_2d);

                                            FamilyInstance instance = document.Create.NewFamilyInstance(new XYZ(0, 0, 0), symbol, StructuralType.NonStructural);

                                            await Task.Delay(1000);

                                            transaction.Commit();
                                        }

                                        Informations = $"Insert {i + 1}/{count}";
                                    }

                                    Informations = "Finished";
                                }
                                catch (Exception ex)
                                { }
                            });

[KennanChan]

How about delaying after the transaction has been committed?

[grizoood]

I tried too but it causes the same exception, for your information it happens on this line: " transaction.Start("Insert");"

[KennanChan]

What is the exception?

[grizoood]

The 1st transaction is commited but the next one does not work.

The exception is: "Starting a transaction from an external application running outside of API context is not allowed." and this happens at the line: " transaction.Start("Insert");"

await RevitTask.RunAsync(
                            async app =>
                            {
                                try
                                {
                                    var document = app.ActiveUIDocument.Document;

                                    int count = 20;

                                    for (int i = 0; i < count; i++)
                                    {
                                        string family_2d = "Family";
                                        string symbol_2d = "Symbol";

                                        using (Transaction transaction = new Transaction(document))
                                        {
                                            transaction.Start("Insert");

                                            var symbol = document.FindSymbol(family_2d, symbol_2d);

                                            FamilyInstance instance = document.Create.NewFamilyInstance(new XYZ(0, 0, 0), symbol, StructuralType.NonStructural);

                                            transaction.Commit();
                                        }

                                        await Task.Delay(1000);

                                        Informations = $"Insert {i + 1}/{count}";
                                    }

                                    Informations = "Finished";
                                }
                                catch (Exception ex)
                                { }
                            });

[KennanChan]

Exactly. The Task.Delay() results in the rest code to be running in a worker thread. You can try to use RevitTask.RunAsync in the loop to execute Revit API

[grizoood]

It works by doing this:

try
{
    int count = 20;

    for (int i = 0; i < count; i++)
    {
        string family_2d = "Family";
        string symbol_2d = "Symbol";

        await RevitTask.RunAsync(
            app =>
            {
                Informations = $"Insert {i + 1}/{count}";

                var document = app.ActiveUIDocument.Document;

                using (Transaction transaction = new Transaction(document))
                {
                    transaction.Start("Insert");

                    var symbol = document.FindSymbol(family_2d, symbol_2d);

                    FamilyInstance instance = document.Create.NewFamilyInstance(new XYZ(0, 0, 0), symbol, StructuralType.NonStructural);

                    transaction.Commit();
                }
            });

        await Task.Delay(1000);
    }

    Informations = "Finished";
}
catch (Exception ex)
{
}

I was thinking of creating a single transaction for the loop how can I do that? Will creating multiple transactions impact processing time?

Another question: If I want to update the "Information" property of my viewmodel, in RevitTask.RunAsync, I have to use the Dispatcher of my interface and do this:

public void UpdateInformations(string message)
{
    _dispatcher.Invoke(() =>
  {
      Informations = message;
  }, DispatcherPriority.Background);
}

[KennanChan]

As far as I know, you can update viewmodel properties without caring about which thread your code is currently running. The viewmodel fires the "PropertyChanged" event to notify the UI to update in proper time.

[KennanChan]

try
{
  RevitTask.RunAsync(async (app) =>
  {
    int count = 20;

    var document = app.ActiveUIDocument.Document;
    Transaction transaction = new Transaction(document);
    transaction.Start("Insert");

    var symbol = document.FindSymbol(family_2d, symbol_2d);

    for (int i = 0; i < count; i++)
    {
      string family_2d = "Family";
      string symbol_2d = "Symbol";

      await RevitTask.RunAsync(
          app =>
          {
            Informations = $"Insert {i + 1}/{count}";
            FamilyInstance instance = document.Create.NewFamilyInstance(new XYZ(0, 0, 0), symbol, StructuralType.NonStructural);
          });

      await Task.Delay(1000);
    }

    transaction.Commit();
    transaction.Dispose();

    Informations = "Finished";
  });
}
catch (Exception ex)
{
}

How about this?

[grizoood]

I get this exception: "System.Runtime.InteropServices.SEHException : 'Un composant externe a levé une exception.'"

[KennanChan]

How did you implement your viewmodel? Especially in the "Information" property

[grizoood]

With your example I get this exception at this line:

FamilyInstance instance = document.Create.NewFamilyInstance(new XYZ(0, 0, 0), symbol, StructuralType.NonStructural);

[KennanChan]

try
{
  RevitTask.RunAsync(async (app) =>
  {
    int count = 20;

    var document = app.ActiveUIDocument.Document;
    Transaction transaction = new Transaction(document);
    transaction.Start("Insert");

    for (int i = 0; i < count; i++)
    {
      string family_2d = "Family";
      string symbol_2d = "Symbol";

      await RevitTask.RunAsync(
          app =>
          {
            Informations = $"Insert {i + 1}/{count}";
            var document = app.ActiveUIDocument.Document;
            var symbol = document.FindSymbol(family_2d, symbol_2d);
            FamilyInstance instance = document.Create.NewFamilyInstance(new XYZ(0, 0, 0), symbol, StructuralType.NonStructural);
          });

      await Task.Delay(1000);
    }

    transaction.Commit();
    transaction.Dispose();

    Informations = "Finished";
  });
}
catch (Exception ex)
{
}

Sorry, I don't have access to Revit at the moment. Please try entering the code again.

[grizoood]

It doesn't change anything, same exception

try
{
    RevitTask.RunAsync(async (app) =>
    {
        int count = 20;

        var document = app.ActiveUIDocument.Document;
        Transaction transaction = new Transaction(document);
        transaction.Start("Insert");

        for (int i = 0; i < count; i++)
        {
            string family_2d = "Family";
            string symbol_2d = "Symbol";

            await RevitTask.RunAsync(
                app2 =>
                {
                    Informations = $"Insert {i + 1}/{count}";
                    var document2 = app2.ActiveUIDocument.Document;
                    var symbol = document2.FindSymbol(family_2d, symbol_2d);
                    FamilyInstance instance = document2.Create.NewFamilyInstance(new XYZ(0, 0, 0), symbol, StructuralType.NonStructural);
                });

            await Task.Delay(1000);
        }

        transaction.Commit();
        transaction.Dispose();

        Informations = "Finished";
    });
}
catch (Exception ex)
{
}

[KennanChan]

I haven't used Revit in years. It seems that the beginning and committing of a transaction cannot be separated in different Revit contexts.

[grizoood]

After this is only a part of code in fact I encounter another problem, when I execute my command my Information property is not updated in my interface, I only see the last message of the loop

[KennanChan]

try
{
  int count = 20;

  for (int i = 0; i < count; i++)
  {
    string family_2d = "Family";
    string symbol_2d = "Symbol";
    
    // update information right before you enter an external event handler
    Informations = $"Insert {i + 1}/{count}";

    await RevitTask.RunAsync(
        app =>
        {

          var document = app.ActiveUIDocument.Document;

          using (Transaction transaction = new Transaction(document))
          {
            transaction.Start("Insert");

            var symbol = document.FindSymbol(family_2d, symbol_2d);

            FamilyInstance instance = document.Create.NewFamilyInstance(new XYZ(0, 0, 0), symbol, StructuralType.NonStructural);

            transaction.Commit();
          }
        });

    await Task.Delay(1000);
  }

  Informations = "Finished";
}
catch (Exception ex)
{
}

Slight changes to the working code.

[KennanChan]

Is the issue still ongoing?

[grizoood]

Yes but I close the issue