NativeActivity NativeActivity NativeActivity NativeActivity Class

Definition

Abstract base class for custom activities that implement execution logic using the Execute(NativeActivityContext) method, which has full access to the runtime’s features.

public ref class NativeActivity abstract : System::Activities::Activity
public abstract class NativeActivity : System.Activities.Activity
type NativeActivity = class
    inherit Activity
Public MustInherit Class NativeActivity
Inherits Activity
Inheritance
NativeActivityNativeActivityNativeActivityNativeActivity
Derived

Examples

The following code sample demonstrates creating a class that inherits from NativeActivity<TResult>. This example is from the Custom Composite using Native Activity sample.

public sealed class MySequence : NativeActivity  
{  
    Collection<Activity> children;  
    Collection<Variable> variables;  
    Variable<int> currentIndex;  
    CompletionCallback onChildComplete;  

    public MySequence()  
        : base()  
    {  
        this.children = new Collection<Activity>();  
        this.variables = new Collection<Variable>();  
        this.currentIndex = new Variable<int>();  
    }  

    public Collection<Activity> Activities  
    {  
        get  
        {  
            return this.children;  
        }  
    }  
    public Collection<Variable> Variables  
    {  
        get  
        {  
            return this.variables;  
        }  
    }  
    protected override void CacheMetadata(NativeActivityMetadata metadata)  
    {  
        //call base.CacheMetadata to add the Activities and Variables to this activity's metadata  
        base.CacheMetadata(metadata);  
        //add the private implementation variable: currentIndex   
        metadata.AddImplementationVariable(this.currentIndex);  
    }                     

    protected override void Execute(NativeActivityContext context)  
    {  
        InternalExecute(context, null);  
    }  
    void InternalExecute(NativeActivityContext context, ActivityInstance instance)  
    {  
        //grab the index of the current Activity  
        int currentActivityIndex = this.currentIndex.Get(context);  
        if (currentActivityIndex == Activities.Count)  
        {  
            //if the currentActivityIndex is equal to the count of MySequence's Activities  
            //MySequence is complete  
            return;  
        }  

        if (this.onChildComplete == null)  
        {  
            //on completion of the current child, have the runtime call back on this method  
            this.onChildComplete = new CompletionCallback(InternalExecute);  
        }  
        //grab the next Activity in MySequence.Activities and schedule it  
        Activity nextChild = Activities[currentActivityIndex];  
        context.ScheduleActivity(nextChild, this.onChildComplete);  

        //increment the currentIndex  
        this.currentIndex.Set(context, ++currentActivityIndex);  
    }  
}  

Constructors

NativeActivity() NativeActivity() NativeActivity() NativeActivity()

When implemented in a derived class, creates a new instance of the derived class.

Properties

CacheId CacheId CacheId CacheId

Gets the identifier of the cache that is unique within the scope of the workflow definition.

(Inherited from Activity)
CanInduceIdle CanInduceIdle CanInduceIdle CanInduceIdle

Gets or sets a value that indicates whether the activity can cause the workflow to become idle.

Constraints Constraints Constraints Constraints

Gets a collection of Constraint activities that can be configured to provide validation for the Activity.

(Inherited from Activity)
DisplayName DisplayName DisplayName DisplayName

Gets or sets an optional friendly name that is used for debugging, validation, exception handling, and tracking.

(Inherited from Activity)
Id Id Id Id

Gets an identifier that is unique in the scope of the workflow definition.

(Inherited from Activity)
Implementation Implementation Implementation Implementation

The execution logic of the activity.

ImplementationVersion ImplementationVersion ImplementationVersion ImplementationVersion

Gets or sets the implementation version of the activity.

Methods

Abort(NativeActivityAbortContext) Abort(NativeActivityAbortContext) Abort(NativeActivityAbortContext) Abort(NativeActivityAbortContext)

When implemented in a derived class, takes actions in response to the activity being aborted.

CacheMetadata(ActivityMetadata) CacheMetadata(ActivityMetadata) CacheMetadata(ActivityMetadata) CacheMetadata(ActivityMetadata)

Not implemented. Use the CacheMetadata(NativeActivityMetadata) method instead.

CacheMetadata(NativeActivityMetadata) CacheMetadata(NativeActivityMetadata) CacheMetadata(NativeActivityMetadata) CacheMetadata(NativeActivityMetadata)

Creates and validates a description of the activity’s arguments, variables, child activities, and activity delegates.

Cancel(NativeActivityContext) Cancel(NativeActivityContext) Cancel(NativeActivityContext) Cancel(NativeActivityContext)

When implemented in a derived class, runs logic to cause graceful early completion of the activity.

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
Execute(NativeActivityContext) Execute(NativeActivityContext) Execute(NativeActivityContext) Execute(NativeActivityContext)

When implemented in a derived class, runs the activity’s execution logic.

GetHashCode() GetHashCode() GetHashCode() GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType() GetType() GetType() GetType()

Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
OnCreateDynamicUpdateMap(NativeActivityUpdateMapMetadata, Activity) OnCreateDynamicUpdateMap(NativeActivityUpdateMapMetadata, Activity) OnCreateDynamicUpdateMap(NativeActivityUpdateMapMetadata, Activity) OnCreateDynamicUpdateMap(NativeActivityUpdateMapMetadata, Activity)

Raises an event when creating a map for the dynamic update.

OnCreateDynamicUpdateMap(UpdateMapMetadata, Activity) OnCreateDynamicUpdateMap(UpdateMapMetadata, Activity) OnCreateDynamicUpdateMap(UpdateMapMetadata, Activity) OnCreateDynamicUpdateMap(UpdateMapMetadata, Activity)

Raises an event when creating a map for the dynamic update.

ShouldSerializeDisplayName() ShouldSerializeDisplayName() ShouldSerializeDisplayName() ShouldSerializeDisplayName()

Indicates whether the DisplayName property should be serialized.

(Inherited from Activity)
ToString() ToString() ToString() ToString()

Returns a String that contains the Id and DisplayName of the Activity.

(Inherited from Activity)
UpdateInstance(NativeActivityUpdateContext) UpdateInstance(NativeActivityUpdateContext) UpdateInstance(NativeActivityUpdateContext) UpdateInstance(NativeActivityUpdateContext)

Updates the instance of NativeActivity.

Applies to