WorkFlow Activity Designer

Question

I want to create a custom Activity. I Need to have a combobox Bind to OData Source

I put a property on my Activity to send the value.

When I select my value from the combobox, the property is not affected

How can i do

lool my designer wpf

<sap:ActivityDesigner
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:sap="clr-namespace:System.Activities.Presentation;assembly=System.Activities.Presentation"
    xmlns:sapv="clr-namespace:System.Activities.Presentation.View;assembly=System.Activities.Presentation"
    xmlns:sapc="clr-namespace:System.Activities.Presentation.Converters;assembly=System.Activities.Presentation"
    xmlns:c="clr-namespace:TFBatchFramwork"  
    xmlns:TFDATAWebReference1="clr-namespace:TFBatchFramwork.TFDATAWebReference1"  
    x:Class="GetBacthVarDesign"    >
    <sap:ActivityDesigner.Resources>
        <ResourceDictionary >
            <sapc:ModelToObjectValueConverter x:Key="ModelToObjectValueConverter"/>
        </ResourceDictionary>
    </sap:ActivityDesigner.Resources>
    <Grid Height="30" HorizontalAlignment="Left" x:Name="grid1" VerticalAlignment="Top" Width="280">
        <Grid.RowDefinitions>
            <RowDefinition Height="30" />
        </Grid.RowDefinitions>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="100" />
            <ColumnDefinition/>
        </Grid.ColumnDefinitions>
        <Label Content="Variables de lot"  Grid.Row="0" Grid.Column="0" VerticalAlignment="Top" />
        <ComboBox  Grid.Row=" 0" Grid.Column=" 1"  ItemsSource="{Binding}"  
            SelectedValue ="{Binding ModelItem.BatchVar, Converter={StaticResource ModelToObjectValueConverter}, Mode=TwoWay  }" 
            VerticalAlignment="Center"   >

        </ComboBox>


    </Grid>
</sap:ActivityDesigner>

Look My vb code

Imports System.Windows.Controls
Imports System.Data.Services.Client

Class GetBacthVarDesign

    Private Context As TFDATAWebReference1.TF5100Context
    Private TrackedVar As DataServiceCollection(Of TFDATAWebReference1.Batch_Var)


    Private Sub GetBacthVarDesign_Loaded(sender As Object, e As Windows.RoutedEventArgs) Handles Me.Loaded
        Context = New TFDATAWebReference1.TF5100Context(New Uri("http://localhost/TFDataWeb/TFDataService.svc"))

        Dim BatchVarQuery = From v In Context.Batch_Var
                       Select v

        TrackedVar = New DataServiceCollection(Of TFDATAWebReference1.Batch_Var)(BatchVarQuery)

        Me.DataContext = TrackedVar

    End Sub
End Class

Look my activity

Imports System.Activities
Imports System.ComponentModel

<Designer(GetType(GetBacthVarDesign))>
Public NotInheritable Class GetBacthVar
    Inherits CodeActivity

    'Définir un argument d'entrée d'activité de type String
    Public Property BatchVar As TFDATAWebReference1.Batch_Var
    'Public Property BatchvarValues As OutArgument(Of Batch_Var_Values)


    ' Si votre activité retourne une valeur, dérivez de CodeActivity(Of TResult)
    ' et retournez la valeur à partir de la méthode Execute.
    Protected Overrides Sub Execute(ByVal context As CodeActivityContext)
        'Obtenir la valeur runtime de l'argument d'entrée Text
        MsgBox(BatchVar.ToString)
        '   context.SetValue(BatchvarValues, General.CreateVBatchVarValue(BatchVar, New BatchContext))
    End Sub
End Class

Thanks for your reply

Answer 1

I am pretty sure that the issue is with the ModelItem binding on your activity designer. I don't think you can do traditional two way binding on the (WF) ModelItem as its not a 'dynamic' type where by you just access the property by name. Generally the way to access the model item properties is via the properties collection -

Me.ModelItem.Properties("BatchVar").SetValue(text)

Rather than

ModelItem.BatchVar = "text"

I have edited your sample code to include the following event handler for your combobox selected item change event.

Xaml -

<ComboBox  Grid.Row=" 0" Grid.Column=" 1"  ItemsSource="{Binding}"  
        SelectedValue ="{Binding ModelItem.BatchVar, Converter={StaticResource ModelToObjectValueConverter}, Mode=TwoWay  }" 
        VerticalAlignment="Center" SelectionChanged="ComboBox_SelectionChanged"   >
</ComboBox>

Code Behind -

Private Sub ComboBox_SelectionChanged(sender As Object, e As Windows.Controls.SelectionChangedEventArgs)

    Dim text As String = DirectCast(sender, Windows.Controls.ComboBox).SelectedItem

    Me.ModelItem.Properties("BacthVar").SetValue(text)

End Sub

HTH