examples/Base/ArraysAndLists/linkedlist/sgllist/src/longnumber.cpp

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// Copyright (c) 2008-2009 Nokia Corporation and/or its subsidiary(-ies).
// All rights reserved.
// This component and the accompanying materials are made available
// under the terms of "Eclipse Public License v1.0"
// which accompanies this distribution, and is available
// at the URL "http://www.eclipse.org/legal/epl-v10.html".
//
// Initial Contributors:
// Nokia Corporation - initial contribution.
//
// Contributors:
//
// Description:
// Contains definition of functions defined in the CLongNumber class.
//



#include "longnumber.h"

CLongNumber* CLongNumber::NewL(CConsoleBase* aConsole)
        {
        CLongNumber* self = new (ELeave) CLongNumber(aConsole);
        self->AddToScheduler();
        return self;
        }

CLongNumber::CLongNumber(CConsoleBase* aConsole):
                                                                                                // Constructor of the base class.
                                                                                                CActive(CActive::EPriorityUserInput),
                                                                                                // Create the linked list.
                                                                                                iNumber(_FOFF(TDigit,iSLink)),
                                                                                                iConsole(aConsole),
                                                                                                // Initialize the iterator.
                                                                                                iIterator(iNumber)
        {
        }


void CLongNumber::AddToScheduler()
        {
        CActiveScheduler::Add(this);
        }

void CLongNumber::RunL()
        {
        // Get the key code.
        TUint8 option = iConsole->KeyCode();
        // Print the selected option.
        _LIT(KTextFormat,"%c\n");
        iConsole->Printf(KTextFormat,option);

        TInt number = option - (TUint)'0';
        // The user has entered a number.
        if(number <10 && number > -1)
                {
                // Append to the list based on iOption.
                switch(iOption)
                        {
                        // Call the TSglQue::AddFirst() function.
                        case EAddFirst:
                                {
                                // Create an object of the TDigit class.
                                TDigit* digit = new (ELeave) TDigit;
                                // Set TDigit::iDigit to the number entered by the user.
                                digit->Set(number);
                                // Add TDigit to the start of the list.
                                iNumber.AddFirst(*digit);
                                iOption = ETOptionNone;
                                }
                                // Print the number.
                                PrintNumber();
                                break;
                        // Call the TSglQue::AddLast() function.
                        case EAddLast:
                                {
                                // Create an object of the TDigit class.
                                TDigit* digit = new (ELeave) TDigit;
                                // Set TDigit::iDigit to the number entered by the user.
                                digit->Set(number);
                                // Add TDigit to the end of the list.
                                iNumber.AddLast(*digit);
                                iOption = ETOptionNone;
                                }
                                // Print the number.
                                PrintNumber();
                                break;
                        case ETOptionNone:
                                _LIT(KInvalidOption,"Invalid Option!\n");
                                iConsole->Printf(KInvalidOption);
                                break;
                        default:
                                iOption = ETOptionNone;
                                break;
                        }
                // Generate an asynchronous read request.
                ReadNumber();
                }
        // The user has not entered a number.
        // Hence, process this request as an option,
        // which represented by the TOption enumeration.
        else
                {
                switch(option)
                        {
                        case 'f':
                                {
                                // Add first.
                                iOption = EAddFirst;
                                _LIT(KTextEnterDigit,"\nEnter a digit\n");
                                iConsole->Printf(KTextEnterDigit);
                                // Read a digit.
                                ReadFunc();
                                }
                                break;
                        case 'l':
                                {
                                // Add last.
                                iOption = EAddLast;
                                _LIT(KTextEnterDigit,"\nEnter a digit\n");
                                iConsole->Printf(KTextEnterDigit);
                                // Read a digit.
                                ReadFunc();
                                }
                                break;
                        case 'r':
                                {
                                if(iNumber.IsEmpty())
                                        {
                                        _LIT(KTextEmpty,"Empty Queue !\n");
                                        iConsole->Printf(KTextEmpty);
                                        ReadNumber();
                                        break;
                                        }
                                // Remove the last element in the list.
                                TDigit* ptr = iNumber.Last();
                                iNumber.Remove(*ptr);
                                delete ptr;
                                // Print the number.
                                PrintNumber();
                                // Read a digit.
                                ReadNumber();
                                }
                                break;
                        default:
                                CActiveScheduler::Stop();
                        }
                }
        }

void CLongNumber::ReadFunc()
        {
        // Wait for a key press event.
        iConsole->Read(iStatus);
        SetActive();
        }

void CLongNumber::ReadNumber()
        {
        _LIT(KTextMenu,"\nMenu\n***\nAdd [f]irst digit to number\nAdd [l]ast digit to number\n[r]emove last digit from number\nAny other NON-NUMERIC key to stop\n***\n");
        iConsole->Printf(KTextMenu);
        ReadFunc();
        }

void CLongNumber::PrintNumber()
        {
        if(iNumber.IsEmpty())
                {
                _LIT(KTextEmpty,"Empty Queue !\n");
                iConsole->Printf(KTextEmpty);                                                   
                }
        _LIT(KTextNumber,"The number is: ");
        iConsole->Printf(KTextNumber);
        // Set the iterator to the first element of the list.
        iIterator.SetToFirst();

        // Iterate the list.
        while(iIterator != NULL)
                {
                // Get the digit.
                TDigit digit = *iIterator;
                // Print the digit.
                _LIT(KTextInt,"%d");
                iConsole->Printf(KTextInt,digit.Get());
                // Go to the next element of the list.
                iIterator++;
                }
        }

void CLongNumber::InitializeIter()
        {
        iIterator.SetToFirst();
        }

TBool CLongNumber::GetNumber(TInt& aValue)
        {
        if(iIterator == NULL)
                {
                // The iterator has reached the end of the list.
                return EFalse;
                }
        TDigit digit = *iIterator;
        aValue = digit.Get();
        return ETrue;
        }

TBool CLongNumber::Slide()
        {
        // Set the iterator to point to the next element.
        iIterator++;
        if(iIterator == NULL)
                {
                // The iterator has reached the end of the list.
                return EFalse;
                }
        return ETrue;
        }

void CLongNumber::DoCancel()
        {
        if(IsActive())
                {
                // Cancel any outstanding read requests.
                iConsole->ReadCancel();
                }
        }

CLongNumber::~CLongNumber()
        {
        // Delete the elements from the list
        if(iIterator)
                {
                iIterator.SetToFirst();
                // Iterate the list and delete all TDigit objects
                TDigit *ptr = iIterator++;
                while (ptr != NULL)
                        {
                        delete ptr;
                        ptr = iIterator++;
                        }
                }
        }

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