NativeActivity Class
Definition
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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
- 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() |
When implemented in a derived class, creates a new instance of the derived class. |
Properties
CacheId |
Gets the identifier of the cache that is unique within the scope of the workflow definition. (Inherited from Activity) |
CanInduceIdle |
Gets or sets a value that indicates whether the activity can cause the workflow to become idle. |
Constraints |
Gets a collection of Constraint activities that can be configured to provide validation for the Activity. (Inherited from Activity) |
DisplayName |
Gets or sets an optional friendly name that is used for debugging, validation, exception handling, and tracking. (Inherited from Activity) |
Id |
Gets an identifier that is unique in the scope of the workflow definition. (Inherited from Activity) |
Implementation |
The execution logic of the activity. |
ImplementationVersion |
Gets or sets the implementation version of the activity. |
ImplementationVersion |
Gets or sets the version of the implementation used. (Inherited from Activity) |
Methods
Abort(NativeActivityAbortContext) |
When implemented in a derived class, takes actions in response to the activity being aborted. |
CacheMetadata(ActivityMetadata) |
Not implemented. Use the CacheMetadata(NativeActivityMetadata) method instead. |
CacheMetadata(NativeActivityMetadata) |
Creates and validates a description of the activity's arguments, variables, child activities, and activity delegates. |
Cancel(NativeActivityContext) |
When implemented in a derived class, runs logic to cause graceful early completion of the activity. |
Equals(Object) |
Determines whether the specified object is equal to the current object. (Inherited from Object) |
Execute(NativeActivityContext) |
When implemented in a derived class, runs the activity's execution logic. |
GetHashCode() |
Serves as the default hash function. (Inherited from Object) |
GetType() |
Gets the Type of the current instance. (Inherited from Object) |
MemberwiseClone() |
Creates a shallow copy of the current Object. (Inherited from Object) |
OnCreateDynamicUpdateMap(NativeActivityUpdateMapMetadata, Activity) |
Raises an event when creating a map for the dynamic update. |
OnCreateDynamicUpdateMap(UpdateMapMetadata, Activity) |
Raises an event when creating a map for the dynamic update. |
OnCreateDynamicUpdateMap(UpdateMapMetadata, Activity) |
Raises an event when creating dynamic update map. (Inherited from Activity) |
ShouldSerializeDisplayName() |
Indicates whether the DisplayName property should be serialized. (Inherited from Activity) |
ToString() |
Returns a String that contains the Id and DisplayName of the Activity. (Inherited from Activity) |
UpdateInstance(NativeActivityUpdateContext) |
Updates the instance of NativeActivity. |