Archived:Using CTextResolver to resolve error texts

ID		Creation date	May 13, 2008
Platform	S60 3rd Edition, FP1	Tested on devices	Nokia N93
Category	Symbian C++	Subcategory	Files/Data

Keywords (APIs, classes, methods, functions): CTextResolver, CTextResolver::NewL(), CTextResolver::ResolveErrorString()

Overview

This code snippet shows how the class CTextResolver is used to resolve corresponding error texts for error codes. The class CTextResolver has two versions of method ResolveErrorString(), the first one is for normal use and the second one is for advanced use. Both of them are demonstrated in this example. It is also possible to give optional error context to map error codes to texts in a unique way. If no context is given (aContext = ECtxAutomatic), the assumption is that error codes are unique.

This snippet can be self-signed.

MMP file

The following libraries are required:

LIBRARY  commonui.lib

Header file

#ifndef __TESTERAPPUI_H__
#define __TESTERAPPUI_H__
 
// INCLUDES
#include <aknappui.h>
 
// FORWARD DECLARATIONS
class CTextResolver;
 
 
class CTesterAppView : public CCoeControl
    {
private:
  // Functions from base classes
  void HandleCommandL(TInt aCommand);
//...  
  void DoHandleCommandL(TInt aCommand);    
 //... 
private:    
    CTextResolver* iTextResolver;
    };
 
#endif // __TESTERAPPUI_H__

Source file

#include <textresolver.h>
 
void CTesterAppUi::ConstructL()
  {
  //...  
   iTextResolver = CTextResolver::NewL(*iCoeEnv);  
  }
 
CTesterAppUi::~CTesterAppUi()
  {
  //...
  delete iTextResolver;
  }
 
void CTesterAppUi::HandleCommandL(TInt aCommand)
  {  
    switch (aCommand)
      {
      case EEikCmdExit:
      case EAknSoftkeyExit:
        Exit();
        break;
 
      case ECommand1:
        {  
        TPtrC errorTextPtr; // pointer to returned error text
 
        TRAPD( errSimple, DoHandleCommandL( aCommand ) );
        if ( errSimple != KErrNone )
          {
          // resolve the given error code 
          errorTextPtr.Set(iTextResolver->ResolveErrorString(errSimple)); 
          }
        else
          {
          // KErrNone, do something....
          } 
        }
        break;
 
      case ECommand2:
        {  
        TInt textId =0;     // ID of the returned text
        TUint flags = 0;    // priority of the returned error 
        TPtrC errorTextPtr; // pointer to returned error text 
 
        TRAPD( errAdvanced, DoHandleCommandL( aCommand ) );
        if ( errAdvanced != KErrNone)
          {
          // resolve the given error code
          errorTextPtr.Set(iTextResolver->ResolveErrorString(errAdvanced, textId, flags)); 
 
            //the flag indicates that the error has no proper explanation
          if (flags & EErrorResBlankErrorFlag)
            {
            // do something...
            }
 
          //the flag indicates that Text Resolver does not support the error code
          if (flags & EErrorResUnknownErrorFlag)
            {
            // do something...
            }
 
          //the flag is returned while processing KErrNoMemory error code
          if (flags & EErrorResOOMFlag)
            {
            // do something...
            }
          }
        else
          {
          // KErrNone do something...
          }
        }
        break;
 
    default:
      Panic(ETesterUi);
      break;
    }
  }
 
void CTesterAppUi::DoHandleCommandL(TInt aCommand)
  {
  //Do Something that might leave...
  User::Leave(KErrNotSupported );    
  }

Postconditions

The class CTextResolver resolves the error text when the method called by the user leaves.

See also

Using_class_CErrorUI_to_display_error_notes