One of the great feature of WF4 is that we can create our own Activity (and its surface) very easy. For example, let's create a PersonInfoActivity:
You will see this in workflow:
But, can we make it more interesting? Say, let it looks like this:
To do this: we need to create an Activity Designer, which is actually a WPF xaml file.
<sap:ActivityDesigner x:Class="MyActivityDesignerLibrary.PersonInfoActivityDesigner"
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:s="clr-namespace:System;assembly=mscorlib"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008" >
<sap:ActivityDesigner.Resources>
<!--<ResourceDictionary>
<sapc:ArgumentToExpressionConverter x:Key="ArgumentToExpressionConverter"/>
</ResourceDictionary>-->
<sapc:ArgumentToExpressionConverter x:Key="ArgumentToExpressionConverter"/>
<DataTemplate x:Key="Collapsed">
<StackPanel>
<TextBlock>This is the collapsed view</TextBlock>
</StackPanel>
</DataTemplate>
<DataTemplate x:Key="Expanded">
<StackPanel>
<Label Content="Name"/>
<sapv:ExpressionTextBox
HintText="Name"
Expression="{Binding Path=ModelItem.name,
Mode=TwoWay,
Converter={StaticResource ArgumentToExpressionConverter },
ConverterParameter=In}"
OwnerActivity="{Binding Path=ModelItem}"
ExpressionType="s:String"/>
<Label Content="Age"/>
<sapv:ExpressionTextBox
HintText="Age"
Expression="{Binding Path=ModelItem.age,
Mode=TwoWay,
Converter={StaticResource ArgumentToExpressionConverter },
ConverterParameter=In}"
OwnerActivity="{Binding Path=ModelItem}"
ExpressionType="s:Int32"/>
</StackPanel>
</DataTemplate>
<Style x:Key="ExpandOrCollapsedStyle"
TargetType="{x:Type ContentPresenter}">
<Setter Property="ContentTemplate"
Value="{DynamicResource Collapsed}"/>
<Style.Triggers>
<DataTrigger Binding="{Binding Path=ShowExpanded}" Value="true">
<Setter Property="ContentTemplate" Value="{DynamicResource Expanded}"/>
</DataTrigger>
</Style.Triggers>
</Style>
</sap:ActivityDesigner.Resources>
<Grid>
<ContentPresenter Style="{DynamicResource ExpandOrCollapsedStyle}" Content="{Binding}" />
</Grid>
</sap:ActivityDesigner>
It is like a face of our activity. But, how could the activity know which face it belong to? We place this attribute
[Designer(typeof(PersonInfoActivityDesigner))]
Ahead of the PersonInfoActivity class:
Ok, that is all we need. This is the final structure:
