aknexslidercontainer.cpp

symbian 中 滚动条的使用 可以用在亮度

            // Displays slider control and information.
            DisplaySliderL( R_AKNEXSLIDER_SLIDER_LAYOUT_VALUE_DECIMAL,
                            KSliderInitialValueOfValueTypeScreen );
            DisplayInformationL( R_AKNEXSLIDER_INFO_VALUETYPE_DECIMAL );
            break;
        case EAknExSliderCmdValueText: // Value text screen.
            // Displays slider control and information.
            iScreenStep = KSliderInitialValueOfTextScreen;
            DisplaySliderL( R_AKNEXSLIDER_SLIDER_LAYOUT_TEXT_VALUE_BARE );
            DisplayInformationL( R_AKNEXSLIDER_INFO_VALUETEXT_BARE );
            break;
        default:
            // Ecepstion : Layout1 screen.
            DisplaySliderL( R_AKNEXSLIDER_SLIDER_LAYOUT1 );
            DisplayInformationL( R_AKNEXSLIDER_INFO_LAYOUT1 );
            break;
        }
    DrawNow();
    }

// ----------------------------------------------------------------------------
// CAknExSliderContainer::DisplaySliderL()
// Creates slider control.
// ----------------------------------------------------------------------------
//
void CAknExSliderContainer::DisplaySliderL( TInt aResourceId, TInt aValue )
    {
    StopDisplaySlider(); // Deletes slider control object.

    if ( !iSlider )
        {
        // Creates slider control object.
        TResourceReader reader;
        iCoeEnv->CreateResourceReaderLC( reader, aResourceId );
        iSlider = new( ELeave ) CAknSlider;
        // Sets edit-mode or view-mode.
        if ( iCurrentFeature == EAknExSliderCmdViewMode )
            {
            iSlider->HandleResourceChange( 
                KEikMessageCaptionedControlNotEditableStateChange );
            }
        else
            {
            iSlider->HandleResourceChange( 
                KEikMessageCaptionedControlEditableStateChange );
            }
        iSlider->ConstructFromResourceL( this, aValue, reader );
        CleanupStack::PopAndDestroy(); // reader

        iSlider->SetObserver( this );

        // Adds slider control to control stack. Slider control can get offered
        // key event.
        iEikonEnv->EikAppUi()->AddToStackL( iSlider );
        }
    }

// ----------------------------------------------------------------------------
// void CAknExSliderContainer::DisplayFormL()
// Creates and displays form.
// ----------------------------------------------------------------------------
//
void CAknExSliderContainer::DisplayFormL( TInt aResourceId )
    {
    CAknExSliderSaveForm* form = CAknExSliderSaveForm::NewL();
    form->ExecuteLD( aResourceId );
    }

// ----------------------------------------------------------------------------
// CAknExSliderContainer::DisplayInformationL()
// Displays the information.
// ----------------------------------------------------------------------------
//
void CAknExSliderContainer::DisplayInformationL( TInt aResourceId )
    {
    // Makes text which is displayed from resource.
    TBuf<KAknExSliderMessageBufLength> information( 0 );
    iCoeEnv->ReadResource( information, aResourceId );

    switch ( iCurrentFeature ) // Screen which is displayed is...
        {
        case EAknExSliderCmdReturn: // Return screen.
        case EAknExSliderCmdSetRange: // Range screen.
        case EAknExSliderCmdSetValue: // Current value screen.
        case EAknExSliderCmdSetStep: // Step size screen.
        case EAknExSliderCmdValueChanged: // Value changed screen.
        case EAknExSliderCmdTypeNotShown: // Value type( not shown ) screen.
        case EAknExSliderCmdTypeBare: // Value type( bare ) screen.
        case EAknExSliderCmdTypePercent: // Value type( percent ) screen.
        case EAknExSliderCmdTypeFraction: // Value type( fraction ) screen.
        case EAknExSliderCmdTypeDecimal: // Value type( decimal ) screen.
            // Sets the value of slider object to text.
            iLabelFormat.SetLength( KSliderClearValue );
            iLabelFormat = information;
            information.SetLength( KSliderClearValue );
            static_cast<void> ( SetValueTextL( information ) );
            break;
        default:
            break;
        }

    SetLabelL( information ); // Sets text to label.
    }

// ----------------------------------------------------------------------------
// CAknExSliderContainer::SetLabelL()
// Sets string in the label.
// ----------------------------------------------------------------------------
//
void CAknExSliderContainer::SetLabelL( TDesC& aInformation )
    {
    if ( iLabel ) // Is label object created?
        {
        TPoint labelPosition( KSliderClearValue, KSliderInformationOffset );
        TSize labelSize( Size() );
        if ( iSlider ) // Is slider control object created?
            {
            // Vertical position of label is bottom position of slider control.
            labelPosition  += iSlider->Position();
            labelPosition.iY += iSlider->Size().iHeight;
            labelSize.iHeight -= iSlider->Size().iHeight;
            }
        // Sets rectangle of label and text.
        iLabel->SetExtent( labelPosition, labelSize );
        iLabel->SetTextL( aInformation );
        }
    }

// ----------------------------------------------------------------------------
// CAknExSliderContainer::SetValueTextL()
// Makes the string which is displayed.
// ----------------------------------------------------------------------------
//
TDesC* CAknExSliderContainer::SetValueTextL( TDes& aTextBuf ) const
    {
    switch ( iCurrentFeature ) // Current screen is...
        {
        case EAknExSliderCmdReturn: // Return value screen.
        case EAknExSliderCmdSetValue: // Current value screen.
        case EAknExSliderCmdValueChanged: // Value changed screen.
        case EAknExSliderCmdTypeNotShown: // Value type( not shown ) screen.
        case EAknExSliderCmdTypeBare: // Value type( bare ) screen.
        case EAknExSliderCmdTypePercent: // Value type( percent ) screen.
        case EAknExSliderCmdTypeFraction: // Value type( fraction ) screen.
            // Sets the current value of slider control to text.
            aTextBuf.Format( iLabelFormat, iSlider->Value() );
            break;
        case EAknExSliderCmdSetRange: // Range screen.
            // Sets the range values of slider control to text.
            aTextBuf.Format( iLabelFormat,
                             KSliderBaseMinValue + iCurrentLabel,
                             KSliderBaseMaxValue - iCurrentLabel );
            break;
        case EAknExSliderCmdSetStep: // Step size screen.
            // Sets the step size to control.
            aTextBuf.Format( iLabelFormat,
                             KSliderStepChangeSize[iCurrentStep] ); 
            break;
        case EAknExSliderCmdTypeDecimal: // Value type( decimal ) screen.
            {
            // Sets the current value of slider control to text.
            TInt sliderValue( iSlider->Value() );
            TInt decimalPlaces( iSlider->DecimalPlaces() );
            TReal64 showValue( sliderValue );
            TReal r;
            Math::Pow10( r, decimalPlaces );
            showValue = showValue / r; 
            aTextBuf.Format( iLabelFormat, showValue );
            break;
            }
        default:
            break;
        }
    return &aTextBuf;
    }

// ----------------------------------------------------------------------------
// CAknExSliderContainer::ChangeLabelL()
// Changes the display of the label.
// ----------------------------------------------------------------------------
//
void CAknExSliderContainer::ChangeLabelL()
    {
    // Updates text which is displayed.
    TBuf<KAknExSliderMessageBufLength> information( 0 );
    TDesC* labelString = SetValueTextL( information );
    SetLabelL( *labelString );
    DrawNow(); // Redraws all components in container.
    }

// ----------------------------------------------------------------------------
// CAknExSliderContainer::ChangeScreenOfTextAppearance()
// Changes the display of the value text in slider of each value type.
// ----------------------------------------------------------------------------
//
void CAknExSliderContainer::ChangeScreenOfTextAppearance()
    {
    if ( iSlider )
        {
        // Displays slider control and information according to iScreenStep.
        switch ( iScreenStep )
            {
            // Value text screen.
            case EAknExSliderChangeText1: // Value type is bare figure.
                DisplaySliderL( R_AKNEXSLIDER_SLIDER_LAYOUT_TEXT_VALUE_BARE );
                DisplayInformationL( R_AKNEXSLIDER_INFO_VALUETEXT_BARE );
                DrawNow();
                break;
            case EAknExSliderChangeText2: // Value is not shown.
                DisplaySliderL( 
                    R_AKNEXSLIDER_SLIDER_LAYOUT_TEXT_VALUE_NOTSHOWN );
                DisplayInformationL( R_AKNEXSLIDER_INFO_VALUETEXT_NOTSHOWN );
                DrawNow();
                break;
            case EAknExSliderChangeText3: // Value type is percentage.
                DisplaySliderL( 
                    R_AKNEXSLIDER_SLIDER_LAYOUT_TEXT_VALUE_PERCENT );
                DisplayInformationL( R_AKNEXSLIDER_INFO_VALUETEXT_PERCENT );
                DrawNow();
                break;
            case EAknExSliderChangeText4: // Value type is fraction.
                DisplaySliderL( 
                    R_AKNEXSLIDER_SLIDER_LAYOUT_TEXT_VALUE_FRACTION );
                DisplayInformationL( R_AKNEXSLIDER_INFO_VALUETEXT_FRACTION );
                DrawNow();
                break;
            case EAknExSliderChangeText5: // Value type is decimal.
                DisplaySliderL( 
                    R_AKNEXSLIDER_SLIDER_LAYOUT_TEXT_VALUE_DECIMAL );
                DisplayInformationL( R_AKNEXSLIDER_INFO_VALUETEXT_DECIMAL );
                DrawNow();
                break;
            default:
                break;
            }
        }
    }

// ----------------------------------------------------------------------------
// CAknExSliderContainer::CountComponentControls()
// Returns number of component.
// ----------------------------------------------------------------------------
//
TInt CAknExSliderContainer::CountComponentControls() const
    {
    TInt count( KSliderCountComponentControls );
    // return the number of slider control
    if ( iSlider )
        {
        count++;
        }
    return count;
    }

// ----------------------------------------------------------------------------
// CAknExSliderContainer::ComponentControl()
// Returns pointer to particular component.
// ----------------------------------------------------------------------------
//
CCoeControl* CAknExSliderContainer::ComponentControl( TInt aIndex ) const
    {
    switch ( aIndex )
        {
        case EAknExSliderComponentLabel:
            return iLabel; // Return pointer to label object.
        case EAknExSliderComponentSlider:
            return iSlider; // Return pointer to slider object.
        default:
            return NULL; // Exception : Returns NULL.
        }
    }

// ----------------------------------------------------------------------------
// CAknExSliderContainer::Draw()
// Clears the window's rectangle.
// ----------------------------------------------------------------------------
//
void CAknExSliderContainer::Draw( const TRect& aRect ) const
    {
    // ( Re )draw the rectangle of frame.
    CWindowGc& gc = SystemGc();
    gc.SetPenStyle( CGraphicsContext::ENullPen );
    gc.SetBrushColor( AKNEXSLIDER_WHITE );
    gc.SetBrushStyle( CGraphicsContext::ESolidBrush );
    gc.DrawRect( aRect );
    }

// ----------------------------------------------------------------------------
// void CAknExSliderContainer::HandleControlEventL()
// Handles the event when state change.
// ----------------------------------------------------------------------------
//
void CAknExSliderContainer::HandleControlEventL( 
    CCoeControl* aControl,
    TCoeEvent aEventType )
    {
    if ( aControl == iSlider && aEventType == EEventStateChanged )
        {
        switch ( iCurrentFeature )
            {
            // Changes label of current value.
            case EAknExSliderCmdValueChanged: // Value changed screen.
            case EAknExSliderCmdTypeNotShown: // Value type( not shown ) screen.
            case EAknExSliderCmdTypeBare: // Value type( bare ) screen.
            case EAknExSliderCmdTypePercent: // Value type( percent ) screen.
            case EAknExSliderCmdTypeFraction: // Value type( fraction ) screen.
            case EAknExSliderCmdTypeDecimal: // Value type( decimal ) screen.
                ChangeLabelL();
                break;
            default:
                break;
            }
        }
    }

// End of File