Class CMsvOperationActiveSchedulerWait

class CMsvOperationActiveSchedulerWait : public CActive;

Description

Utility class used to wait until an asynchronous messaging operation has completed.

To use the class:

1. Create a new CMsvOperationActiveSchedulerWait object

2. Call the messaging function that returns the asynchronous operation. The operation observer parameter should be the iStatus word of the CMsvOperationActiveSchedulerWait object. This means that the CMsvOperationActiveSchedulerWait object will be signalled when the operation completes.

3. Call the CMsvOperationActiveSchedulerWait object's Start() function. This sets the object to be active.

These steps cause the program to wait until the operation completes.

     CMsvOperationActiveSchedulerWait* waiter=CMsvOperationActiveSchedulerWait::NewLC();
     CMsvOperation* op = function_returning_opLC(waiter->iStatus);
     waiter->Start();

     CleanupStack::PopAndDestroy(2); // op, waiter

Derivation

• CBase - Base class for all classes to be instantiated on the heap

• CActive - The core class of the active object abstraction

• CMsvOperationActiveSchedulerWait - Utility class used to wait until an asynchronous messaging operation has completed

Members

Defined in CMsvOperationActiveSchedulerWait:
DoCancel(), NewLC(), RunL(), Start(), ~CMsvOperationActiveSchedulerWait()

Inherited from CActive:
Cancel(), Deque(), EPriorityHigh, EPriorityIdle, EPriorityLow, EPriorityStandard, EPriorityUserInput, Extension_(), IsActive(), IsAdded(), Priority(), RunError(), SetActive(), SetPriority(), TPriority, iStatus

Inherited from CBase:
Delete(), operator new()

static IMPORT_C CMsvOperationActiveSchedulerWait *NewLC(TInt aPriority=EPriorityStandard);

Description

Allocates and constructs a new CMsvOperationActiveSchedulerWait object.

The new object is added to the active scheduler and left on the cleanup stack.

Parameters

TInt aPriority Active object priority. It has a default value of EPriorityStandard.

Return value

CMsvOperationActiveSchedulerWait * New CMsvOperationActiveSchedulerWait object

Leave codes

KErrNoMemory

IMPORT_C ~CMsvOperationActiveSchedulerWait();

Description

Destructor.

Any active request on the object is cancelled.

IMPORT_C void Start();

Description

Sets the object to be active, and wait until the request is completed.

private: virtual void RunL();

Description

Handles a request completion event.

The function stops the object waiting, and allows the program to resume execution after the Start() function call.

See also:

• CActive::RunL()

private: virtual void DoCancel();

Description

Implements cancellation of an outstanding request.

See also:

• CActive::DoCancel()