/*

* Copyright (c) 2005-2007 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:  Floating point field for CEikMfne

*

*/

#ifndef CAKNMFNEFLOAT_H

#define CAKNMFNEFLOAT_H

#include <eikmfne.h>

/**

 * A floating point field for multi-field numeric editors.

 * 

 * Features of this field:

 * - Functions NOT exported, header file NOT exported anywhere. Commented

 *   for convenience.

 * - Fixed number of fractional digits, to implement the logic seen

 *   in other MFNE's. Can be zero or more, although using a value

 *   greater than ~15 doesn't really make sense (nor is it tested)

 * - Togglable support for NaN value. In case the field is left empty

 *   and NaN is allowed, the field's value equals NaN. Also if the value

 *   is set to be NaN, the field appears to be empty.

 * - Localization support with the CEikMfneNumber-type functions.

 *

 * @lib eikctl.lib

 * @since S60 v3.2

 */

NONSHARABLE_CLASS( CAknMfneFloat ) : public CEikMfneField

    {

public:

    /**

     * Field's flags 

     */

    enum TFlags

        {

        /** If set, the field will allow an empty (NaN) value */

        EAllowNaN = 0x0001

        };

    /**

     * Used to determine what characters are allowed in HandleKey().

     * iAllowedInputFlags is a combination of these. These

     * are pretty self-explanatory.

     */

    enum TAllowedInputFlags

        {

        EDigit            = 0x0001,

        EDecimalSeparator = 0x0002,

        EMinusSign        = 0x0004

        };

    virtual ~CAknMfneFloat();

    /**

     * Creates a new CAknMfneFloat field.

     * To complete construction, call the following functions after this:

     * - SetFlags(), if needed

     * - SetLimits()

     * - SetValue()

     *

     * @since S60 v3.2

     * @param aMaxFractionalDigits The maximum number of fractional digits

     * @return The new CAknMfneFloat object

     */

    static CAknMfneFloat* NewL(

        TInt aMaxFractionalDigits);

    /**

     * Set the minimum and maximum limits.

     *

     * @since S60 v3.2

     * @param aMinimumValue The minimum value

     * @param aMaximumValue The maximum value

     * @return If ETrue, the call caused field's value to change

     */

    TBool SetLimits(

        TReal aMinimumValue,

        TReal aMaximumValue);

    /**

     * Gets the limits

     *

     * @since S60 v3.2

     * @param aMinimumValue On return, the minimum value

     * @param aMaximumValue On return, the maximum value

     */     

    void GetLimits(

        TReal& aMinimumValue,

        TReal& aMaximumValue) const;

    /**

     * Sets the value of the field

     *

     * @since S60 v3.2

     * @param aValue The value to be set

     * @return ETrue, if the value was valid and not changed. The value is

     *         also considered to be valid in case it is rounded to the

     *         limits of the editor's maximum fractional digits.

     */

    TBool SetValue( TReal aValue );

    /**

     * Gets the value currently in the field

     *

     * @since S60 v3.2

     * @return The value in the field, parsed by TLex

     */

    TReal Value() const;

    /**

     * Calls SetTextFromValueAndNormalize() with the value parsed from

     * the current text.

     *

     * @since S60 v3.2

     * @return ETrue, if the value was significantly changed while

     *         normalizing.

     */

    TBool NormalizeValue();

    /**

     * Sets the maximum number of fractional digits.

     *

     * @since S60 v3.2

     * @param aMaxFractionalDigits The maximum number of fractional digits.

     */

    void SetMaxFractionalDigits( TInt aMaxFractionalDigits );

    /**

     * Gets the maximum number of fractional digits.

     *

     * @since S60 v3.2

     * @return The maximum number of fractional digits.

     */

    TInt MaxFractionalDigits() const;

    /**

     * Sets the field's digit type to match the current number type,

     * as set from General Settings. Calls SetDigitType().

     *

     * @since S60 v3.2

     */

    void RefreshDigitType();

    /**

     * Sets the field's digit type.

     *

     * @since S60 v3.2

     * @param aDigitType The digit type to be set.

     */

    void SetDigitType( TDigitType aDigitType );

    /**

     * Gets the field's digit type.

     *

     * @since S60 v3.2

     * @return The field's digit type.

     */

    TDigitType DigitType() const;

    /**

     * Sets the field's flags.

     *

     * @since S60 v3.2

     * @param aFlags The flags to be set, see TFlags.

     */

    void SetFlags( TUint aFlags );

    /**

     * Gets the field's flags.

     *

     * @since S60 v3.2

     * @return The field's flags.

     */

    TUint Flags() const;

private:

    CAknMfneFloat( TInt aMaxFractionalDigits );

    void ConstructL();

// From CEikMfneField

public:

    TInt MaximumWidthInPixels(

        const CFont& aFont,

        TBool aShrinkToMinimumSize);

    TCoeInputCapabilities InputCapabilities() const;

    TBool IsEditable() const;

    // these functions may only be called if

    // IsEditable returns ETrue - all TBool&/TInt& parameters

    // in these functions must be first set to EFalse/0 by the caller

    THighlightType HighlightType() const;

    void HandleKey(

        const CFont& aFont,

        const TKeyEvent& aKeyEvent,

        TBool aInterpretLeftAndRightAsEarEvents,

        TBool& aDataAltered,

        TInt& aHighlightIncrement);

    /**

     * Called when MFNE wants to move highlight/focus from this field.

     * If the entered value contains an error (i.e. is too large or small),

     * aError is set to ETrue.

     */

    void HandleDeHighlight(

        const CFont& aFont,

        CEikonEnv& aEikonEnv,

        TBool& aDataAltered,

        TBool& aError);

private:

    const TDesC& Text() const;

// New internal methods

private:

    TInt MaxNumOfChars() const;

    TReal ValueFromText(const TDesC& aText) const;

    TBool SetTextFromValueAndNormalize( TReal aValue );        

    TChar DecimalSeparator() const;

    void UpdateAllowedInput();

    void ClearFieldIfNecessary( TBool& aDataAltered );

    void TryAppend( TChar aChar, TUint aAllowedFlags, TBool& aDataAltered );

    void TryDelete( TInt aDigits, TBool& aDataAltered );

    TChar NormalizeDigit( TChar aChar ) const;

private:

    TReal   iMinimumValue;

    TReal   iMaximumValue;

    TInt    iMaxPositiveIntegerDigits;

    TInt    iMaxNegativeIntegerDigits;

    TInt    iMaxFractionalDigits;

    HBufC*  iText;

    TBool   iIsBeingEditedWithCursor;

    TDigitType iDigitType;

    TUint   iAllowedInputFlags;

    TUint   iFlags;        

    TChar   iMinusSign;

    TChar   iZero;

    };

#endif // CAKNMFNEFLOAT_H

// end of File