helllo...
i am new in symbian.c++ ......
i use below code that was in my book.,
but there is some problems :

it s code :
PHP Code:
#include "CDelayedHello.h"
#include "eikdef.h"
#include "eikenv.h"
void CDelayedHello::DoCancel()
    {
        
iTimer.Cancel();
    }
TInt CDelayedHello::RunError(TInt aError)
    {
        return 
KErrNone;
    }
EXPORT_C TInt CActive::RunError(TInt aError)
    {
        return 
aError;
    }
void CDelayedHello::RunL()
    {
        
iEnv->InfoMsg(R_ACTIVEHELLO_TEXT_HELLO);
    }

CDelayedHelloCDelayedHello::NewL()
    {
        
CDelayedHelloself = new (ELeaveCDelayedHello();
        
CleanupStack::PushL(self);
        
self->ConstructL();
        
CleanupStack::Pop(self);
        return 
self;
    }
CDelayedHello::CDelayedHello() : CActive(CActive::EPriorityStandard)
    {
        
CActiveScheduler::Add(this);
    }
void CDelayedHello::ConstructL()
    {
        
iEnv CEikonEnv::Static();
        
User::LeaveIfError(iTimer.CreateLocal());
    }
CDelayedHello::~CDelayedHello()
    {
        
Cancel();
        
iTimer.Close();
    }    
void CDelayedHello::SetHello(TTimeIntervalMicroSeconds32 aDelay)
    {
        
iEnv->InfoMsg(R_ACTIVEHELLO_TEXT_HELLO);
    } 
and its header :
PHP Code:
#ifndef CDELAYEDHELLO_H_
#define CDELAYEDHELLO_H_

#include <e32base.h>
#include <eikdef.h>
#include <eikenv.h>
class CDelayedHello : public CActive
    
{
public:
    
// Construct/destruct
    
static CDelayedHelloNewL();
    ~
CDelayedHello();
    
// Request
    
void SetHello(TTimeIntervalMicroSeconds32 aDelay);
    private:
    
// Construct/destruct
    
CDelayedHello();
    
void ConstructL();
    
// from CActive
    
void RunL();
    
void DoCancel();
    
TInt RunError(TInt aError);
private:
    
RTimer iTimer// Has
    
CEikonEnviEnv// Uses
    
};

#endif /* CDELAYEDHELLO_H_ */ 

the problem is :
PHP Code:
Creation Time    Description    Resource    Path    Location    Type
1308030934710    undefined identifier 
'R_ACTIVEHELLO_TEXT_HELLO'    CDelayedHello.cpp    /test2/src    line 26    C/C++ Problem 
and

PHP Code:
Creation Time    Description    Resource    Path    Location    Type
1308030956070    Undefined symbol
'class CCoeEnv * CCoeEnv::Static(void) (?Static@CCoeEnv@@SAPAV1@XZ)'    test2        Unknown    C/C++ Problem