Categories: Symbian C++ | Code Examples | Files/Data | S60 3rd Edition, Feature Pack 1

This page was last modified 09:54, 28 May 2008.

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Overview

This code snippet shows how to delete schedules and tasks using the class RScheduler. To be able to delete a schedule, it cannot contain any scheduled tasks, so the tasks must be deleted from it first. Tasks can be deleted from a schedule by using method DeleteTask() with a specific task ID. This method returns KErrNotFound if the task is not found. The method DeleteSchedule() is used to delete schedules by giving it a schedule handle.

In this example new example tasks are created to time-based and condition-based schedules. The created task IDs are then used to delete these tasks. Finally this example shows how to delete all tasks one by one from a given schedule and after that the empty schedule is deleted with the method DeleteSchedule().

This snippet can be self-signed.

MMP file

The following libraries are required:

LIBRARY             schsvr.lib

Preconditions

Before this code snippet can be executed, ExampleTaskHandler.exe must be created and time-based and condition-based schedules with example tasks must be scheduled. See code snippets CS000986 - Creating and registering a task handler with RScheduler, CS000987 - Creating persistent and transient schedules with RScheduler, and CS000988 - Creating a condition-based schedule with RScheduler for more information.

Resource files

.rss

RESOURCE MENU_PANE r_schedulerexample_menu
    {
    items = 
        {
        //...
        MENU_ITEM {command = EDeleteExample;           txt = "DeleteExample";},        
        MENU_ITEM {command = EAknSoftkeyExit;          txt = "Exit";}
        };
    }

.hrh

enum TSchedulerExampleIds
    {
  //...
    EDeleteExample
    };

Header file

#ifndef __SCHEDULEREXAMPLEAPPUI_H__
#define __SCHEDULEREXAMPLEAPPUI_H__
 
#include <csch_cli.h> // RScheduler
#include <schinfo.h>  // TSchedulerItemRef, TTaskInfo... 
 
class CSchedulerExampleAppUi : public CAknAppUi
    {
    //...
public:    
    void HandleCommandL(TInt aCommand);
    //...
private:    
    TInt ScheduleNewTaskL(TInt aScheduleId, RScheduler& aScheduler, TInt& aNewTaskId);    
    
    TInt DeleteConditionBasedScheduleTaskByIdL(RScheduler& aScheduler, 
                                               TInt aScheduleId, 
                                               TInt aTaskId, 
                                               TBool& aDeleted);
  
    TInt DeleteTimeBasedScheduleTaskByIdL(RScheduler& aScheduler, 
                                          TInt aScheduleId, 
                                          TInt aTaskId, 
                                          TBool& aDeleted);
      
    TInt DeleteAllScheduleTasksL(RScheduler& aScheduler, TInt aScheduleId);
 
    //...    
private:
 
    RScheduler iScheduler;
    
    TSchedulerItemRef iPersistentScheduleHandle;
    TSchedulerItemRef iConditionScheduleHandle;    
    };
    
#endif // __SCHEDULEREXAMPLEAPPUI_H__

Source file

void CSchedulerExampleAppUi::ConstructL()
    {
    //...
    User::LeaveIfError(iScheduler.Connect());
    
    _LIT(KExampleTaskHandlerExe, "ExampleTaskHandler.exe");
    TFileName exampleHandler(KExampleTaskHandlerExe);
        
    User::LeaveIfError(iScheduler.Register(exampleHandler, CActive::EPriorityStandard));    
    }
    
CSchedulerExampleAppUi::~CSchedulerExampleAppUi()
    {
 
    //...    
    iScheduler.Close(); 
    }    
 
void CSchedulerExampleAppUi::HandleCommandL(TInt aCommand)
  {
  TBuf<100> Text1; //first line of dialog text 
  TBuf<100> Text2; //second line of dialog text
      
  switch(aCommand)
    {
    case EEikCmdExit:
    case EAknSoftkeyExit:
      Exit();
      break;
//...
    case EDeleteExample:
      {
      TInt err(KErrNone);
      
      TInt timeTaskId=-1;
      TInt conditionTaskId=-1;
  
      TBool timeTaskDeleted=EFalse;
      TBool conditionTaskDeleted=EFalse;
            
      //schedule a new example task to the time-based schedule and store the task ID    
      err = ScheduleNewTaskL(iPersistentScheduleHandle.iHandle, iScheduler, timeTaskId);
            
      Text1.Append(_L("TimeTask:"));
      Text1.AppendNum(timeTaskId);
            
      if(err == KErrNone )
        { 
        //delete the example task you just created using the stored ID
        err = DeleteTimeBasedScheduleTaskByIdL(iScheduler,
 iPersistentScheduleHandle.iHandle, timeTaskId, timeTaskDeleted);
                         
        if(err == KErrNone && timeTaskDeleted)
          {
          //task deleted succesfully...
          Text1.Append(_L("del OK\n"));                  
          }
        else
          {
          //delete task failed...
          Text1.Append(_L("del NOK\n"));                   
          }                          
        }
      
      //schedule a new example task to the condition-based schedule and store the task ID
      err = ScheduleNewTaskL(iConditionScheduleHandle.iHandle, 
iScheduler, conditionTaskId);
            
      Text1.Append(_L("CondTask:"));
      Text1.AppendNum(conditionTaskId);
            
      if(err == KErrNone )
        {  
        //delete the just created example task using the stored ID 
        err = DeleteConditionBasedScheduleTaskByIdL(iScheduler,
 iConditionScheduleHandle.iHandle, conditionTaskId, conditionTaskDeleted);
               
        if(err == KErrNone && conditionTaskDeleted)
          {
          //task deleted succesfully...
          Text1.Append(_L(" del OK\n"));          
          }
        else
          {
          //delete task failed... 
          Text1.Append(_L(" del NOK\n"));          
          }                          
        }
           
      //delete all tasks from the given schedule      
      err = DeleteAllScheduleTasksL(iScheduler, iPersistentScheduleHandle.iHandle);
            
      if(err == KErrNone)
        Text2.Append(_L("del all OK\n"));
      else
        Text2.Append(_L("del all NOK\n"));
         
      //delete the given schedule   
      err = iScheduler.DeleteSchedule(iPersistentScheduleHandle.iHandle);
            
      if(err == KErrNone)
        Text2.Append(_L("del sch OK\n"));
      else
        Text2.Append(_L("del sch NOK\n"));
  
      CEikonEnv::Static()->InfoWinL(Text1, Text2);
      }
      break;
      
   default:
     //Panic(ESchedulerExampleUi);
     break;
     }
  }  
    
 
TInt CSchedulerExampleAppUi::ScheduleNewTaskL(TInt aScheduleId, 
                  RScheduler& aScheduler, TInt& aNewTaskId)
  {
  TInt ret(KErrNone);
  
  TTaskInfo taskInfo;
  taskInfo.iTaskId      = 0;
  taskInfo.iName        = _L("NewTask");
  taskInfo.iPriority    = 2;
  taskInfo.iRepeat      = 0;
  HBufC* data           = _L("NewTaskData").AllocLC();
  ret = aScheduler.ScheduleTask(taskInfo, *data, aScheduleId);
 
  aNewTaskId = taskInfo.iTaskId;
  
  CleanupStack::PopAndDestroy(); // data
  
  return ret;
  }
 
TInt CSchedulerExampleAppUi::DeleteConditionBasedScheduleTaskByIdL(
                                                      RScheduler& aScheduler, 
                                                      TInt aScheduleId, 
                                                      TInt aTaskId, 
                                                      TBool& aDeleted )  
  {
  TInt ret(KErrNone);
  TScheduleType type;
  TBool deleted = EFalse;
  
  ret = aScheduler.GetScheduleTypeL(aScheduleId, type);
    
  if(ret != KErrNone)
    {
    aDeleted = EFalse;
    return ret;
    }
      
  if(type != EConditionSchedule)
      {
      //the given schedule id is not of a condition-based schedule
      aDeleted = EFalse;
      return KErrGeneral;
      }
  
  CArrayFixFlat<TTaskInfo>* tasks = new (ELeave) CArrayFixFlat<TTaskInfo>(1);
  CleanupStack::PushL(tasks);
 
  TTsTime time;
  TScheduleState2 state;
  CArrayFixFlat<TTaskSchedulerCondition>* conditions = 
new (ELeave) CArrayFixFlat<TTaskSchedulerCondition>(1);        
  CleanupStack::PushL(conditions);
    
  tasks->Reset();
  ret = aScheduler.GetScheduleL(aScheduleId, 
                  state, 
                 *conditions, 
                 time,
                *tasks);
  CleanupStack::PopAndDestroy(conditions);
  
  for (TInt index = 0 ; index < tasks->Count(); index++)
    {
    if( tasks->At(index).iTaskId == aTaskId )
      {
      ret = iScheduler.DeleteTask(tasks->At(index).iTaskId);
      (ret == KErrNone )?deleted = ETrue:deleted = EFalse ;
      break;
      }    
    }
  
  if(deleted)
    aDeleted = ETrue;
  else
    aDeleted = EFalse;
 
  CleanupStack::PopAndDestroy(tasks);
  
  return ret;
  }
 
 
TInt CSchedulerExampleAppUi::DeleteTimeBasedScheduleTaskByIdL(RScheduler& aScheduler, 
                                                              TInt aScheduleId, 
                                                              TInt aTaskId, 
                                                              TBool& aDeleted )  
  {
  TInt ret(KErrNone);
  TScheduleType type;
  TBool deleted = EFalse; 
  
  ret = aScheduler.GetScheduleTypeL(aScheduleId, type);
    
  if(ret != KErrNone)
    {
    aDeleted = EFalse;
    return ret;
    }
      
  if(type != ETimeSchedule)
      {
      //the given schedule id is not time based schedule
      aDeleted = EFalse;
      return KErrGeneral;
      }
  
  CArrayFixFlat<TTaskInfo>* tasks = new (ELeave) CArrayFixFlat<TTaskInfo>(1);
  CleanupStack::PushL(tasks);
  
  TTsTime time;
  TScheduleState2 state;
  CArrayFixFlat<TScheduleEntryInfo2>* entries = 
new (ELeave) CArrayFixFlat<TScheduleEntryInfo2>(1);
  CleanupStack::PushL(entries);
    
  tasks->Reset();
  ret = aScheduler.GetScheduleL(aScheduleId, 
                  state, 
                  *entries, 
                  *tasks, 
                  time);
  
  CleanupStack::PopAndDestroy(entries);
  TInt count = tasks->Count();
  for (TInt index = 0 ; index < count; index++)
    {
    if( tasks->At(index).iTaskId == aTaskId )
      {
      ret = iScheduler.DeleteTask(tasks->At(index).iTaskId);
      (ret == KErrNone )?deleted = ETrue:deleted = EFalse ;
      break;
      }    
    }
  
  if(deleted)
    aDeleted = ETrue;
  else
    aDeleted = EFalse;
  
  CleanupStack::PopAndDestroy(tasks);
  
  return ret;  
  }
 
 
TInt CSchedulerExampleAppUi::DeleteAllScheduleTasksL(RScheduler& aScheduler, 
                                                     TInt aScheduleId)  
  {
  TInt ret(KErrNone);
  TScheduleType type;
 
  TTsTime time;
  TScheduleState2 state;
  CArrayFixFlat<TTaskInfo>* tasks = NULL;
  
  User::LeaveIfError(aScheduler.GetScheduleTypeL(aScheduleId, type));
     
  //the given schedule is time-based schedule
  if(type == ETimeSchedule)
      {
      
      tasks = new (ELeave) CArrayFixFlat<TTaskInfo>(1);
      CleanupStack::PushL(tasks);
      
      CArrayFixFlat<TScheduleEntryInfo2>* entries = 
new (ELeave) CArrayFixFlat<TScheduleEntryInfo2>(1);
      CleanupStack::PushL(entries);
        
      tasks->Reset();
      User::LeaveIfError(aScheduler.GetScheduleL(aScheduleId, 
                      state, 
                      *entries, 
                      *tasks, 
                      time));
      
      CleanupStack::PopAndDestroy(entries);
      TInt count = tasks->Count();
      for (TInt index = 0 ; index < count; index++)
        {
         User::LeaveIfError(iScheduler.DeleteTask(tasks->At(index).iTaskId));
        }
            
      CleanupStack::PopAndDestroy(tasks);
      }
  //the given schedule is a condition-based schedule
  else if (type == EConditionSchedule)
    {    
    tasks = new (ELeave) CArrayFixFlat<TTaskInfo>(1);
    CleanupStack::PushL(tasks);
 
    CArrayFixFlat<TTaskSchedulerCondition>* conditions = 
new (ELeave) CArrayFixFlat<TTaskSchedulerCondition>(1);        
    CleanupStack::PushL(conditions);
        
    tasks->Reset();
    User::LeaveIfError(aScheduler.GetScheduleL(aScheduleId, 
                      state, 
                     *conditions, 
                     time,
                    *tasks));
    CleanupStack::PopAndDestroy(conditions);
      
    for (TInt index = 0 ; index < tasks->Count(); index++)
      {
      User::LeaveIfError(iScheduler.DeleteTask(tasks->At(index).iTaskId));
      }
 
    CleanupStack::PopAndDestroy(tasks);
    
    }
  //Cannot determine schedule type
  else
    {
    User::LeaveIfError(KErrGeneral);
    }
  
  return ret;  
  }

Postconditions

The new example tasks are created to time-based and condition-based schedules and then deleted. After this, all time-based schedule tasks are deleted one by one and finally the schedule itself is deleted.

See also

• CS000986 - Creating and registering a task handler with RScheduler
• CS000987 - Creating persistent and transient schedules with RScheduler
• CS000988 - Creating a condition-based schedule with RScheduler
• CS000989 - Getting schedule and task info using RScheduler
• CS000990 - Getting schedule and task count using RScheduler
• CS000991 - Editing a schedule using RScheduler