class CMsvOperationActiveSchedulerWait : public CActive |
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
Public Member Functions | |
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~CMsvOperationActiveSchedulerWait() | |
IMPORT_C CMsvOperationActiveSchedulerWait * | NewLC(TInt) |
IMPORT_C void | Start() |
Private Member Functions | |
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CMsvOperationActiveSchedulerWait(TInt) | |
void | DoCancel() |
void | RunL() |
Inherited Enumerations | |
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CActive:TPriority |
Private Attributes | |
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CActiveSchedulerWait | iActiveSchedulerWait |
Inherited Attributes | |
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CActive::iStatus |
CMsvOperationActiveSchedulerWait | ( | TInt | aPriority | ) | [private] |
TInt aPriority |
void | DoCancel | ( | ) | [private, virtual] |
Implements cancellation of an outstanding request.
This function is called as part of the active object's Cancel().
It must call the appropriate cancel function offered by the active object's asynchronous service provider. The asynchronous service provider's cancel is expected to act immediately.
DoCancel() must not wait for event completion; this is handled by Cancel().
IMPORT_C CMsvOperationActiveSchedulerWait * | NewLC | ( | TInt | aPriority = EPriorityStandard | ) | [static] |
TInt aPriority = EPriorityStandard |
void | RunL | ( | ) | [private, virtual] |
Handles an active object's request completion event.
A derived class must provide an implementation to handle the completed request. If appropriate, it may issue another request.
The function is called by the active scheduler when a request completion event occurs, i.e. after the active scheduler's WaitForAnyRequest() function completes.
Before calling this active object's RunL() function, the active scheduler has:
1. decided that this is the highest priority active object with a completed request
2. marked this active object's request as complete (i.e. the request is no longer outstanding)
RunL() runs under a trap harness in the active scheduler. If it leaves, then the active scheduler calls RunError() to handle the leave.
Note that once the active scheduler's Start() function has been called, all user code is run under one of the program's active object's RunL() or RunError() functions.
CActiveScheduler::WaitForAnyRequest
TRAPD