/*

* Copyright (c) 2002-2004 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:           

*       Provides the CAknFepUICtrlCandidatePane definition.

*

*/

#ifndef __AKN_FEP_CANDIDATE_PANE_H__

#define __AKN_FEP_CANDIDATE_PANE_H__

#include <e32std.h>

#include <coecntrl.h>

#include "AknFepUiCtrlContainerChinese.h"

/**

* TPage holds the start index, end index and start position in buffer of every display page

*/

struct TPage

    {

    TInt iStartIndex;

    TInt iEndIndex;

    };

/**

 * Pane which displays the Chinese Candidates.

 */

class MAknFepUICtrlCandidatePane

    {

public:

    enum

        {

        EOneCandidate = 1,

        EMaxCandidates = 10,

        EMaxPages = 10,

        EPhraseLength = 10

        };

    /**

     * each candidate can be in a certain mode, which may affect its layout. Note

     * that only stroke is needed at this time (for components), but more modes could be added 

     * later if the LAF spec changes.

     */

    enum TCandidateMode

        {

        ECandidateModeNormal,

        ECandidateModeStroke

        };

public:

    /**

     * Allows the client to set a descriptor pointer into an existing buffer of 

     * data, avoiding unnecessary copying of data.

     * <p> Note that if the buffer contains less characters than the current

     * visible count, then the remaining characters will not be displayed. 

     * <p> Note also that if the current selection falls outside the range

     * of the size of the new buffer, it will be made not visible. 

     * However, the current highlighted state remains, so if the selection 

     * is set once more to a valid entry (or if the buffer is set to a length that 

     * includes the currently selected position), and the highlight is still enabled,

     * the highlight will reappear.

     *

     * @param aBufferPtr descriptor that contains the candidates for display,

     *                              could be a pointer into a subset of a larger descriptor 

     *                              that contains all the candidates. Note that only the 

     *                              first EMaxCandidates of aBuffer will be used. 

     *                              Length must be > 0.

     */

    virtual void SetCandidateBuffer(const TDesC& aBuffer) = 0;

    /**

     * This function sets the highlighted status of the pane for rendering purposes. 

     * If the Pane is highlighted it displays the current selected Candidate, 

     * plus numbers with each of the other Candidates. 

     * 

     * @param aHighlighted ETrue if the highlight is to be set

     *                                  EFalse if the highlight is to be removed

     */

    virtual void SetHighlighted(TBool aHighlighted) = 0;

    /**

     * enable/disable the rendering of the Horizontal Scroll Arrows. 

     *

     * @param aValue if ETrue, enable the arrows

     *                          if EFalse, disable the arrrows

     */

    virtual void ShowHorizontalScrollArrows(TBool aValue) = 0;

    /**

     * enable/disable the rendering of the up Scroll Arrows. 

     *

     * @param aValue if ETrue, enable the arrows

     *  if EFalse, disable the arrrows

     */

    virtual void ShowUpScrollArrows(TBool aValue) = 0;

    /**

     * enable/disable the rendering of the down Scroll Arrows. 

     *

     * @param aValue if ETrue, enable the arrows

     *  if EFalse, disable the arrrows

     */

    virtual void ShowDownScrollArrows(TBool aValue) = 0;

     /**

     * enable/disable the rendering of the left Scroll Arrows. 

     *

     * @param aValue if ETrue, enable the arrows

     *  if EFalse, disable the arrrows

     */

    virtual void ShowLeftScrollArrows(TBool aValue) = 0;

        /**

     * enable/disable the rendering of the right Scroll Arrows. 

     *

     * @param aValue if ETrue, enable the arrows

     *  if EFalse, disable the arrrows

     */

    virtual void ShowRightScrollArrows(TBool aValue) = 0;

    /**

     * enable/disable the rendering of the Vertical Scroll Arrows. 

     *

     * @param aValue if ETrue, enable the arrows

     *                          if EFalse, disable the arrrows

     */

    virtual void ShowVerticalScrollArrows(TBool aValue) = 0;

    /**

     * enable/disable the rendering of the candidate ordinal numbers

     *

     * @param aValue if ETrue, enable the ordinals

     *                          if EFalse, disable the ordinals

     *

     */

    virtual void ShowCandidateOrdinals(TBool aValue) = 0;

    /**

     * This function returns the number of Candidates that are visible in the pane 

     * in its current configuration.

     *

     * @return number of candidates that are currently visible

     */

    virtual TInt VisibleCandidateCount() const = 0;

    /**

     * Select the first visible item in the candidate buffer

     *

     * @return ETrue if success, EFalse if no items visible

     *

     */

    virtual TBool SelectFirst() = 0;

    /**

     * Select the first visible phrase item in the candidate buffer

     *

     * @return ETrue if success, EFalse if no items visible

     *

     */

    virtual TBool SelectFirstPhrase() = 0;

    /**

     * Select the last visible item in the candidate buffer

     *

     * @return ETrue if success, EFalse if no items visible

     *

     */

    virtual TBool SelectLast() = 0;

    /**

     * Select the last visible phrase item in the candidate buffer

     *

     * @return ETrue if success, EFalse if no items visible

     *

     */

    virtual TBool SelectLastPhrase() = 0;

    /**

     * Select the next visible item

     *

     * @return ETrue if success, 

     *              EFalse if no items visible, or if already on last visible item

     */

    virtual TBool SelectNext() = 0;

    /**

     * Select the previous visible item

     *

     * @return ETrue if success, 

     *              EFalse if no items visible, or if already on first visible item

     */

    virtual TBool SelectPrev() = 0;

    /**

     * This function selects the given index. 

     * <p> Note that if the new selected index is within the visible count, 

     * but falls on a candidate that is not valid (i.e. if it falls outside the

     * length of the candidate buffer) then nothing happens and EFalse is returned

     *

     * @param aIndex If aIndex falls outside length of candidate buffer, 

     *                          then return EFalse to indicate failure. 

     * @return ETrue if index was valid, EFalse if index not valid

     */

    virtual TBool SelectIndex(TInt aIndex, TBool selected = ETrue) = 0;

    /**

     * This function returns the selected index of the Candidate Pane. 

     * 

     * @return the index of the selected item. If the Pane is not highlighted it returns 0.

     *

     */

    virtual TInt SelectedIndex() const = 0;

    /**

     * This function returns the character at index of the current selection

     *

     * @return a descrptor containing the character that is currently selected.

     *              If the currect selection falls outside the length of the current buffer,

     *              then return a null descriptor

     *

     */

    virtual TPtrC CurrentCandidate() const = 0;

    /**

     * This function returns the phrase at index of the current selection

     *

     * @return a descrptor containing the character that is currently selected.

     *              If the currect selection falls outside the length of the current buffer,

     *              then return a null descriptor

     *

     */

    virtual TPtrC CurrentPhraseCandidate() const = 0;

    /**

	*	Split phrase candidates into pages 

	*/

    virtual void SplitPhraseCandidatesIntoPages() = 0;

    /**

	*	Navigate to next page 

	*/

    virtual void NextCandidatePage(void) = 0;

    /**

	*	Navigate to previous page 

	*/

    virtual void PreviousCandidatePage(void) = 0;

    /**

	*	Return candidate array 

	*/

    virtual CDesCArrayFlat* CandidateArray(void) = 0;

    /**

	*	Set phrase candidate buffer

	*/

    virtual void SetCandidateBuffer(void) = 0;

	/**

	*	Reset candidate pane state and variables

	*/

	virtual void ResetCandidateState() = 0;

	/**

	 *	To test whether current page is the first page

	 */

	virtual TBool IsFirstPage() = 0;

	/**

	 *	To test whether current page is the last page

	 */

	virtual TBool IsLastPage() = 0;

   /**

     *  To set all the cnadidate label invisible(phrase creation)

     */

    virtual void SetInVisiable() = 0;

	/**

	 *	To test whether need to get new candidate page

	 */

	virtual TBool NeedGetNewCandidatePage() = 0;

    };

#endif //__AKN_FEP_CANDIDATE_PANE_H__

// End of file