examples/AppFramework/txtshell/txtview.cpp

// Copyright (c) 2000-2009 Nokia Corporation and/or its subsidiary(-ies).
// All rights reserved.
// License: "Symbian Foundation License v1.0" to Symbian Foundation
// members and "Symbian Foundation End User License Agreement v1.0"
// to non-members at the URL
// "http://www.symbianfoundation.org/legal/licencesv10.html".
//
// Initial Contributors:
// Nokia Corporation - initial contribution.
//
// Contributors:
//
// Description:
//

#include "txtexamp.h"

#include <txtrich.h>

CViewControl::~CViewControl()
        {
        delete iTextView; // text view
        delete iLayout; // text layout
        delete iRichText; // contained text object
        delete iCharFormatLayer; // char format layer
        delete iParaFormatLayer; // para format layer
        delete iBitmap; // line cursor character bitmap
        }

void CViewControl::UpdateModelL()
        {
        // Create all constant literal descriptors used in this function, 
        // e.g. for message text

        _LIT(KText1, "To be, or not to be, that is the question; \
whether 'tis nobler in the mind to suffer the \
slings and arrows of outrageous fortune, or \
to stand against a sea of troubles, and by \
opposing end them."); 
        _LIT(KText4,"Format band set. Num formatted lines=%d");
        _LIT(KText5,"Format band unset. Num formatted lines=%d");
        _LIT(KPathAndFile,"\\resource\\apps\\cursors.mbm");
        _LIT(KCDrive,"\\");
        _LIT(KZDrive,"Z:");
        _LIT(KStatus0,"Initialised - with grey fill colour");
        _LIT(KStatus1,"Added lots of text");
        _LIT(KStatus2,"Selected first paragraph");
        _LIT(KStatus3,"Formatted the selected text (and cancelled selection)");
        _LIT(KStatus6,"Set 20 pixel line cursor margin and 2 cursors");
        _LIT(KStatus7,"Reset the view rectangle - old wrapping still applies");
        _LIT(KStatus8,"Text wrapping set to new view rectangle");
        _LIT(KStatus9,"View rectangle and wrap width reset");
        _LIT(KStatus10,"Horizontal scroll left");
        _LIT(KStatus11,"Scrolling DOWN, blank space NOT scrolled");
        _LIT(KStatus12,"Back to top and horizontal scroll right");
        _LIT(KStatus13,"Reset();");
        _LIT(KStatusDefault,"(overshot!!)");

        switch (Phase())
                {
        case 0:
                {
                // Preparation for following cases:
                TCharFormat charFormat;
                TCharFormatMask charFormatMask;
                iUpdateModelDoesRedraw=ETrue; 
                        // NextPhaseL() should call DrawNow() for the first case only
                // Create rich text object to be displayed in the text view
                iParaFormatLayer=CParaFormatLayer::NewL(); // required para format
                iCharFormatLayer=CCharFormatLayer::NewL(); // required char format
                                // empty text objects
                iRichText=CRichText::NewL(iParaFormatLayer, iCharFormatLayer);
                // prerequisites for view - viewing rectangle
                iViewRect=Rect();
                iViewRect.Shrink(3,3);
                // context and device
                CWindowGc& gc=SystemGc(); // get graphics context
                CBitmapDevice* device=(CBitmapDevice*) (gc.Device()); // device
                // Construct the layout object used by the text view,
                // specifying wrap width (= width of viewing rectangle)
                iLayout=CTextLayout::NewL(iRichText,iViewRect.Width());
                // Construct text view
                iTextView=CTextView::NewL(iLayout, iViewRect,
                        device,
                        device,
                        &Window(),
                        &iCoeEnv->RootWin(), // window group, needed for cursor
                        &iCoeEnv->WsSession()
                        ); // new view
                // Set paragraph fill color and font height.
                // For visibility, set font height to 10 point.
                charFormatMask.SetAttrib(EAttFontHeight); 
                        // height attribute only is relevant
                charFormat.iFontSpec.iHeight=200; // set to 10 point (200 twips)
                iRichText->ApplyCharFormatL(charFormat,charFormatMask,0,0);
                // Apply grey paragraph fill colour 
                CParaFormat* paraFormat=CParaFormat::NewL();
                TParaFormatMask paraFormatMask;
                paraFormat->iFillColor=TRgb(204,204,204); // Light grey
                paraFormatMask.SetAttrib(EAttFillColor);
                        // fill colour attribute only is relevant
                iRichText->ApplyParaFormatL(paraFormat,paraFormatMask,0,0);
                iTextView->FormatTextL();
                iFormObserver->NotifyStatus(KStatus0);
                delete paraFormat;
                break;
                }
        case 1:
                {
                // Set some character formatting
                iCharFormatMask.SetAttrib(EAttFontStrokeWeight);  
                
                iCharFormat.iFontSpec.iFontStyle.SetStrokeWeight(EStrokeWeightBold);

                // apply formatting - pos and length are irrelevent
                iRichText->ApplyCharFormatL(iCharFormat,iCharFormatMask, 0,0);
                
                // insert lots of text
                for (TInt count=0;count<5;count++) // insert a paragraph, *5
                        {       
                        iRichText->InsertL(iRichText->DocumentLength(),KText1); // text
                        iRichText->InsertL(iRichText->DocumentLength(),
                                CEditableText::EParagraphDelimiter); // end para
                        };
                TCursorSelection selection(0, iRichText->DocumentLength());
                        // start and length of the inserted block
                iTextView->HandleInsertDeleteL(selection, 0); 
                        // zero deleted characters 
                iFormObserver->NotifyStatus(KStatus1);
                break;
                }
        case 2:
                {
                // Select the first paragraph
                TInt pos=1;
                TUint scanMask=CPlainText::EScanToUnitEnd;
                iRichText->ScanParas(pos,scanMask);
                        // get end position of current para
                // move cursor to end of para and select it
                iTextView->SetDocPosL(pos,ETrue); // ETrue = select the range
                iFormObserver->NotifyStatus(KStatus2);
                break;
                }
        case 3:
                {
                // Apply italics to the selected region
                TCursorSelection cursorSelection;
                TCharFormat charFormat;
                TCharFormatMask charFormatMask;
                // Set italics
                charFormat.iFontSpec.iFontStyle.SetPosture(EPostureItalic); 
                charFormatMask.SetAttrib(EAttFontPosture); 
                        // font posture attribute only is relevant
                cursorSelection=iTextView->Selection(); // get range of selection
                TInt lowerPos=cursorSelection.LowerPos();
                TInt length=cursorSelection.Length();
                // Apply formatting to range
                iRichText->ApplyCharFormatL(charFormat,charFormatMask,lowerPos,length);
                iTextView->HandleRangeFormatChangeL(cursorSelection); // reformat from here
                iTextView->CancelSelectionL(); // remove selection and redraw
                iFormObserver->NotifyStatus(KStatus3);
                break;
                }
        case 4:
                {
                TBuf<80> message;
                // Set formatting to the band only and display the number of formatted lines.
                iLayout->SetAmountToFormat(CTextLayout::EFFormatBand);
                iTextView->HandleGlobalChangeL(); // global layout change 
                message.Format(KText4,iLayout->NumFormattedLines());
                iFormObserver->NotifyStatus(message);
                break;
                }
        case 5:
                {
                TBuf<80> message;
                // Set formatting to the whole document, then display the number of 
                // formatted lines.
                iLayout->SetAmountToFormat(CTextLayout::EFFormatAllText);
                iTextView->HandleGlobalChangeL(); // global layout change 
                message.Format(KText5,iLayout->NumFormattedLines());
                iFormObserver->NotifyStatus(message);
                break;
                }
        case 6:
                {
                // Set line cursor margin and line cursor bitmap
                iTextView->SetMarginWidths(0,20); // zero label margin, 20 pixel line cursor margin
                iTextView->DrawL(iViewRect); // update the view (SetMarginWidths() doesn't redraw)
                // Load in bitmap to represent line cursor.
                iBitmap=new(ELeave) CFbsBitmap();
                TBufC<40> pathandfile(KPathAndFile);
                TParse    bitmapFileName;
                TBufC<2>  c_drive(KCDrive);
                TBufC<2>  z_drive(KZDrive);

            bitmapFileName.Set(pathandfile,&c_drive,NULL);
                
                if (iBitmap->Load(bitmapFileName.FullName())) 
                        // can't find cursor bitmap on C: drive, so try Z:
                        {
                        bitmapFileName.Set(pathandfile,&z_drive,NULL);
                        iBitmap->Load(bitmapFileName.FullName());
                        iTextView->SetLineCursorBitmap(iBitmap);
                        iTextView->SetCursorVisibilityL(TCursor::EFCursorVisible,
                                TCursor::EFCursorFlashing); 
                        // both cursors now visible - flashing text cursor
                        iFormObserver->NotifyStatus(KStatus6);
                        }
                break;
                }
        case 7:
                {
                // Reset the view rectangle.
                // Before doing this, clear the existing one,
                // (the view should really be implemented as a control, in a container control,
                // and then the background would get cleared nicely by the container).
                ActivateGc();
                SystemGc().Clear(iViewRect);
                DeactivateGc();
                // Shrink the view rectangle by 40 pixels both directions
                iViewRect.Shrink(40,40);
                iTextView->SetViewRect(iViewRect);
                iTextView->DrawL(iViewRect); // Redraw the completely revamped view 
                        // (SetViewRect() does not do a redraw)
                iFormObserver->NotifyStatus(KStatus7);
                break;
                }
        case 8:
                {
                // Wrap text to new view rectangle.
                // New wrap width = new view rect width minus total margin width.
                // First calculate the total margin width.
                TInt labelMarginWidth;
                TInt lineCursorMarginWidth;
                iTextView->MarginWidths(labelMarginWidth,lineCursorMarginWidth);
                iLayout->SetWrapWidth(iViewRect.Width()-(labelMarginWidth+lineCursorMarginWidth));
                iLayout->ForceNoWrapping(EFalse); // Ensure wrapping on
                iTextView->HandleGlobalChangeL();
                iFormObserver->NotifyStatus(KStatus8);
                break;
                }
        case 9:
                {
                // Reset view rectangle back to old dimensions and set wrapping
                // width accordingly
                TInt labelMarginWidth;
                TInt lineCursorMarginWidth;
                iTextView->MarginWidths(labelMarginWidth,lineCursorMarginWidth);
                iViewRect.Grow(40,40);
                        // Increase view rectangle by 40 pixels both directions
                iTextView->SetViewRect(iViewRect);
                iLayout->SetWrapWidth(iViewRect.Width()-(labelMarginWidth+lineCursorMarginWidth));
                iTextView->HandleGlobalChangeL();
                iFormObserver->NotifyStatus((KStatus9));
                break;
                }
        case 10:
                // Horizontal scrolling
                iTextView->SetHorizontalScrollJump(40); // scroll jump is 40 pixels
                iTextView->ScrollDisplayL(TCursorPosition::EFLeft,CTextLayout::EFAllowScrollingBlankSpace); 
                        // scroll to the left (scrolling blank space is allowed)
                iFormObserver->NotifyStatus(KStatus10);
                break;
        case 11:
                {
                // Vertical scrolling
                iFormObserver->NotifyStatus(KStatus11);
                TInt pixelsScrolled;
                // Scroll down to the bottom of the document, 
                do
                        pixelsScrolled=iTextView->ScrollDisplayL(TCursorPosition::EFLineDown,
                                CTextLayout::EFDisallowScrollingBlankSpace);
                while (pixelsScrolled);
                break;
                }
        case 12:
                {
                // Horizontal scroll back to left margin and to top of doc
                iFormObserver->NotifyStatus(KStatus12);
                TInt pixelsScrolled;
                do
                        pixelsScrolled=iTextView->ScrollDisplayL(TCursorPosition::EFLineUp);            
                while (pixelsScrolled);
                iTextView->ScrollDisplayL(TCursorPosition::EFRight); 
                        // scroll right (horizontal scroll jump value=40 pixels)
                break;
                }
        case 13:
                {
                // Reset document. 
                iRichText->Reset(); // change whole document!
                iTextView->FormatTextL(); // so format the whole lot
                iTextView->DrawL(iViewRect); // and draw it afresh
                iFormObserver->NotifyStatus(KStatus13);
                break;
                }
        default:
                iFormObserver->NotifyStatus(KStatusDefault);
                break;
                }
        }

void CViewControl::Draw(const TRect& aRect) const
        {
        // draw surround
        CGraphicsContext& gc=SystemGc(); // context to draw into
        TRect rect=Rect(); // screen boundary
        gc.DrawRect(rect); // outline screen boundary
        rect.Shrink(1,1);
        gc.SetPenColor(KRgbWhite);
        gc.DrawRect(rect);
        rect.Shrink(1,1);
        gc.SetPenColor(KRgbBlack);
        gc.DrawRect(rect);
        // draw editable text - will work unless OOM
        TInt err;
        TRAP(err,iTextView->DrawL(aRect));
        }

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