How to hold, resume and swap calls

CTelephony::Hold() puts a call on hold. Pass it the ID of the call to hold. The ID is the CTelephony::TCallId returned when you dialled or answered the call.

Before calling CTelephony::Hold(), check that your phone supports call holding; see Dynamic call capabilities.

CTelephony::Hold() is asynchronous; use CTelephony::EHoldCancel to cancel.

For example:

#include <e32base.h>
#include <Etel3rdParty.h>

class CClientApp : public CActive
    { 

private:
    CTelephony* iTelephony;
    CTelephony::TCallId iCallId;

public:
    CClientApp(CTelephony* aTelephony, CTelephony::TCallId aCallId);
    TInt SomeFunction();

private:
    /*
       These are the pure virtual methods from CActive that  
       MUST be implemented by all active objects
       */
    void RunL();
    void DoCancel();
   };

CClientApp::CClientApp(CTelephony* aTelephony, CTelephony::TCallId aCallId)
    : CActive(EPriorityStandard),
      iTelephony(aTelephony),
      iCallId(aCallId)
    {
    //default constructor
    }

TInt CClientApp::SomeFunction()
    {
    // Check that the phone supports holding calls.
    CTelephony::TCallCapsV1 callCapsV1;
    CTelephony::TCallCapsV1Pckg callCapsV1Pckg(callCapsV1);
    iTelephony->GetCallDynamicCaps(iCallId, callCapsV1Pckg);

    if( callCapsV1.iControlCaps & CTelephony::KCapsHold )
       {
       // The call represented by 'iCallId' can be put on hold
       iTelephony->Hold(iStatus, iCallId);
       SetActive();
       return KErrNone;
       }
    else
       {
       // The call cannot be put on hold; 
       // return an error indicate this.
       return KErrNotSupported;
       }
    }

void CClientApp::RunL()
    {
    if(iStatus==KErrNone)
       {} // The call has been held successfully;
    }

void CClientApp::DoCancel()
    {
    iTelephony->CancelAsync(CTelephony::EHoldCancel);
    }

Remember to link to the Etel3rdParty.lib and euser.lib libraries.

Once a call is on hold, you can resume the call by with CTelephony::Resume(). It is very similar to CTelephony::Hold(): check that the phone supports resuming (see Dynamic call capabilities), then pass CTelephony::Resume() the ID of the call to resume.

CTelephony::Resume() is asynchronous; use CTelephony::EResumeCancel to cancel.

Note that you can terminate a call while it is on hold; you do not have to resume it first.

For example:

#include <e32base.h>
#include <Etel3rdParty.h>

class CClientApp : public CActive
    { 

private:
    CTelephony* iTelephony;
    CTelephony::TCallId iCallId;

public:
    CClientApp(CTelephony* aTelephony, CTelephony::TCallId aCallId);
    TInt SomeFunction();

private:
    /*
       These are the pure virtual methods from CActive that  
       MUST be implemented by all active objects
       */
    void RunL();
    void DoCancel();
   };

CClientApp::CClientApp(CTelephony* aTelephony, CTelephony::TCallId aCallId)
    : CActive(EPriorityStandard),
      iTelephony(aTelephony),
      iCallId(aCallId)
    {
    //default constructor
    }

TInt CClientApp::SomeFunction()
    {
    // Check that the phone supports Resuming calls.
    CTelephony::TCallCapsV1 callCapsV1;
    CTelephony::TCallCapsV1Pckg callCapsV1Pckg(callCapsV1);
    iTelephony->GetCallDynamicCaps(iCallId, callCapsV1Pckg);

    if( callCapsV1.iControlCaps & CTelephony::KCapsResume )
       {
       // The call represented by 'iCallId' can be resumed
       iTelephony->Resume(iStatus, iCallId);
       SetActive();
       return KErrNone;
       }
    else
       {
       // The call cannot be resumed; 
       // return an error indicate this.
       return KErrNotSupported;
       }
    }

void CClientApp::RunL()
    {
    if(iStatus==KErrNone)
       {} // The call has been resumed successfully;
    }

void CClientApp::DoCancel()
    {
    iTelephony->CancelAsync(CTelephony::EResumeCancel);
    }

Remember to link to the Etel3rdParty.lib and euser.lib libraries.

Call CTelephony::Swap() when you have an active call and a call on hold. It makes the held call active and the puts the active call on hold. Pass it the IDs of the two calls. The IDs are the CTelephony::TCallIds returned when you dialled or answered the calls.

Before calling CTelephony::Swap(), check that your phone supports call swapping; see Dynamic call capabilities.

CTelephony::Swap() is asynchronous; use CTelephony::ESwapCancel to cancel.

For example:

#include <e32base.h>
#include <Etel3rdParty.h>

class CClientApp : public CActive
    { 

private:
    CTelephony* iTelephony;
    CTelephony::TCallId iCallIdA;
    CTelephony::TCallId iCallIdB;

public:
    CClientApp(CTelephony* aTelephony, CTelephony::TCallId aCallIdA, CTelephony::TCallId aCallIdB);
    TInt SomeFunction();

private:
    /*
       These are the pure virtual methods from CActive that  
       MUST be implemented by all active objects
       */
    void RunL();
    void DoCancel();
   };

CClientApp::CClientApp(CTelephony* aTelephony, CTelephony::TCallId aCallId)
    : CActive(EPriorityStandard),
      iTelephony(aTelephony),
      iCallIdA(aCallIdA)
      iCallIdB(aCallIdB)
    {
    //default constructor
    }

TInt CClientApp::SomeFunction()
    {
    // Check that the phone supports Resuming calls.
    CTelephony::TCallCapsV1 callCapsV1;
    CTelephony::TCallCapsV1Pckg callCapsV1Pckg(callCapsV1);
    iTelephony->GetCallDynamicCaps(iCallId, callCapsV1Pckg);

    if( callCapsV1.iControlCaps & CTelephony::KCapsSwap )
       {
       // The call represented by 'iCallId' can be swapped
       iTelephony->Swap(iStatus, iCallIdA, iCallIdB);
       SetActive();
       return KErrNone;
       }
    else
       {
       // The call cannot be swapped; 
       // return an error indicate this.
       return KErrNotSupported;
       }
    }

void CClientApp::RunL()
    {
    if(iStatus==KErrNone)
       {} // The call has been swapped successfully;
    }

void CClientApp::DoCancel()
    {
    iTelephony->CancelAsync(CTelephony::ESwapCancel);
    }

Remember to link to the Etel3rdParty.lib and euser.lib libraries.