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TBidiText Class Reference

class TBidiText

This class works as a replacement for HBufC in those cases where a small amount of text is being formatted simply. The text must be all of one style and broken into lines of all the same length. The number of lines and the text itself is specified on construction, and the text may then be re-broken, re-truncated and re-drawn with non-leaving functions.

Public Member Functions
IMPORT_C TDirectionality Directionality ()
IMPORT_C TPtrC DisplayText ()
IMPORT_C void DrawText ( CGraphicsContext &, const TPoint &)
IMPORT_C void DrawText ( CGraphicsContext &, const TPoint &, TInt , CGraphicsContext::TTextAlign )
IMPORT_C void DrawText ( CGraphicsContext &, const TPoint &, TInt )
IMPORT_C TPtrC LineOfDisplayText ( TInt , TInt &)
IMPORT_C TSize MinimumSize ( TInt , const CFont &, TInt , TInt , const MLineBreaker *)
IMPORT_C TBidiText * NewL ( TInt , TInt )
IMPORT_C TBidiText * NewL (const TDesC &, TInt )
IMPORT_C TBidiText * NewL (const TDesC &, TInt , TDirectionality )
IMPORT_C TInt NumberOfLinesInDisplayText ()
IMPORT_C TDirectionality ScriptDirectionality ( TLanguage )
IMPORT_C TInt SetText (const TDesC &, RRunInfoArray &)
IMPORT_C TInt SetText (const TDesC &, TDirectionality , RRunInfoArray &)
IMPORT_C void SetTruncationChar ( TChar )
IMPORT_C TPtrC Text ()
IMPORT_C TDirectionality TextDirectionality (const TDesC &, TBool *)
IMPORT_C TChar TruncationChar ()
IMPORT_C void WrapText ( TInt , const CFont &, const MLineBreaker *, TInt )
IMPORT_C void WrapText ( TInt , const CFont &, const MLineBreaker *)
IMPORT_C TInt WrappingWidth ()
Protected Member Functions
TBidiText ()
Private Member Functions
TInt DoWrapText ( TInt , const CFont &, const MLineBreaker *, TInt , TText *&, TInt &, TInt16 *)
Public Member Enumerations
enum TDirectionality { ELeftToRight  = 0, ERightToLeft  = 1 }
enum TPanicCodes { EPanicRunArrayNull }

Constructor & Destructor Documentation

TBidiText()

TBidiText ( ) [protected]

Member Functions Documentation

Directionality()

IMPORT_C TDirectionality Directionality ( ) const

Returns the directionality of the text.

DisplayText()

IMPORT_C TPtrC DisplayText ( ) const

Returns the text as prepared for display, provided that WrapText has been called. If WrapText has not been called, a panic will result.

DoWrapText(TInt, const CFont &, const MLineBreaker *, TInt, TText *&, TInt &, TInt16 *)

TInt DoWrapText ( TInt aWrappingWidth,
const CFont & aFont,
const MLineBreaker * aBreaker,
TInt aMaxLines,
TText *& aOutputText,
TInt & aNumLines,
TInt16 * aLineWidthArray
) const [private]

Parameters

TInt aWrappingWidth
const CFont & aFont
const MLineBreaker * aBreaker
TInt aMaxLines
TText *& aOutputText
TInt & aNumLines
TInt16 * aLineWidthArray

DrawText(CGraphicsContext &, const TPoint &)

IMPORT_C void DrawText ( CGraphicsContext & aGc,
const TPoint & aLeft
) const

Draws the first line of the text. WrapText must have been called already. Alignment is taken from the directionality of the text.

Parameters

CGraphicsContext & aGc The graphics context to draw the text to. The graphics context's font is assumed to have been set to the same font that was passed to the previous call to WrapText.
const TPoint & aLeft The left extreme of the baseline. Note that this should not be at the very edge of the available space, or characters such as "W" with left side bearings may be truncated.

DrawText(CGraphicsContext &, const TPoint &, TInt, CGraphicsContext::TTextAlign)

IMPORT_C void DrawText ( CGraphicsContext & aGc,
const TPoint & aLeft,
TInt aBaseLineSpacing,
CGraphicsContext::TTextAlign aAlignment
) const

Draws all of the text. WrapText must have been called already.

Parameters

CGraphicsContext & aGc The graphics context to draw the text to. The graphics context's font is assumed to have been set to the same font that was passed to the previous call to WrapText.
const TPoint & aLeft The left extreme of the baseline. Note that this should not be at the very edge of the available space, or characters such as "W" with left side bearings may be truncated.
TInt aBaseLineSpacing The spacing between each line. If 0, only the first line is drawn.
CGraphicsContext::TTextAlign aAlignment How to position the text horizontally.

DrawText(CGraphicsContext &, const TPoint &, TInt)

IMPORT_C void DrawText ( CGraphicsContext & aGc,
const TPoint & aLeft,
TInt aBaseLineSpacing
) const

Draws all of the text. Alignment is taken from the directionality of the text. WrapText must have been called already.

Parameters

CGraphicsContext & aGc The graphics context to draw the text to. The graphics context's font is assumed to have been set to the same font that was passed to the previous call to WrapText.
const TPoint & aLeft The left extreme of the baseline. Note that this should not be at the very edge of the available space, or characters such as "W" with left side bearings may be truncated.
TInt aBaseLineSpacing The spacing between each line. If 0, only the first line is drawn.

LineOfDisplayText(TInt, TInt &)

IMPORT_C TPtrC LineOfDisplayText ( TInt aLine,
TInt & aWidthInPixels
) const

Returns the text as prepared for display, provided that WrapText has been called. If WrapText has not been called, a panic will result.

Parameters

TInt aLine Line number to retrieve.
TInt & aWidthInPixels

MinimumSize(TInt, const CFont &, TInt, TInt, const MLineBreaker *)

IMPORT_C TSize MinimumSize ( TInt aWrappingWidth,
const CFont & aFont,
TInt aLineGap,
TInt aMaxLines = -1,
const MLineBreaker * aBreaker = NULL
) const

Calculate the minimum size needed to draw the current text, given the specified wrapping width, font, and line gap. Calling this method will not rewrap the object's text.

Parameters

TInt aWrappingWidth The maximum width of the text in pixels. Note that this distance should be slightly less than the available width to allow for characters such as "W" which can have side-bearings that leak into the margins.
const CFont & aFont The font that will provide the character metrics.
TInt aLineGap The number of empty pixels between two lines of text. Note that this is not the same as the baseline spacing, which is the font height plus the line gap.
TInt aMaxLines = -1 Number of lines to restrict wrapping to. The truncation character will be used if the text is too long for this number of lines. The number of lines wrapped to may be greater than the figure passed to NewL, and that figure will be used if the number of lines is specified as -1. If 0 (zero) is specified no limit is applied.
const MLineBreaker * aBreaker = NULL An object for breaking the lines. May be NULL for default behaviour.

NewL(TInt, TInt)

IMPORT_C TBidiText * NewL ( TInt aReservedMaxLength,
TInt aMaxLines
) [static]

Creates a bidirectional text object with enough room for up to aReservedMaxLength number of characters. The number of characters that will actually fit (when calling SetText() ) might be slightly less than aReservedMaxLength, as each change between a left-to-right and a right-to-left sub-string (and the other way around) needs about two characters worth of memory.

Parameters

TInt aReservedMaxLength The maximum number of characters.
TInt aMaxLines The maximum number of lines that this text will need to be split into. Must be at least 1, but should not be too large, as each potential line takes an extra 8 bytes of memory.

NewL(const TDesC &, TInt)

IMPORT_C TBidiText * NewL ( const TDesC & aText,
TInt aMaxLines
) [static]

Creates a bidirectional text object with directionality determined by the text itself. Use this for text that has been obtained from a resource file.

Parameters

const TDesC & aText The text in logical order.
TInt aMaxLines The maximum number of lines that this text will need to be split into. Must be at least 1, but should not be too large, as each potential line takes an extra 8 bytes of memory.

NewL(const TDesC &, TInt, TDirectionality)

IMPORT_C TBidiText * NewL ( const TDesC & aText,
TInt aMaxLines,
TDirectionality aDirectionality
) [static]

Creates a bidirectional text object with directionality determined by aDirectionality. Use this for text that has come from user input.

Parameters

const TDesC & aText The text in logical order.
TInt aMaxLines The maximum number of lines that this text will need to be split into. Must be at least 1, but should not be too large, as each potential line takes an extra 8 bytes of memory.
TDirectionality aDirectionality Direction to use.

NumberOfLinesInDisplayText()

IMPORT_C TInt NumberOfLinesInDisplayText ( ) const

Reports the number of lines in the text to be drawn.

WrapText must have been called already.

ScriptDirectionality(TLanguage)

IMPORT_C TDirectionality ScriptDirectionality ( TLanguage aLanguage ) [static]

Returns the directionality of a given language.

Parameters

TLanguage aLanguage Language.

SetText(const TDesC &, RRunInfoArray &)

IMPORT_C TInt SetText ( const TDesC & aText,
RRunInfoArray & aRunInfoArray
)

Sets the text of the bidirectional text object with directionality determined by the text itself. Use this for text that has been obtained from a resource file.

Parameters

const TDesC & aText The text in logical order.
RRunInfoArray & aRunInfoArray

SetText(const TDesC &, TDirectionality, RRunInfoArray &)

IMPORT_C TInt SetText ( const TDesC & aText,
TDirectionality aDirectionality,
RRunInfoArray & aRunInfoArray
)

Sets the text of the bidirectional text with directionality determined by aDirectionality. Use this for text that has come from user input.

panic
Bidi EBidiPanic_RunArrayNull The call to RRunInfoArray::OpenL() has not been made prior to this call to TBidiText::SetText()

Parameters

const TDesC & aText The text in logical order.
TDirectionality aDirectionality Direction to use.
RRunInfoArray & aRunInfoArray

SetTruncationChar(TChar)

IMPORT_C void SetTruncationChar ( TChar aTruncateWith )

Sets the character that will be added at the end of the text if the whole text cannot fit into the space specified.

Parameters

TChar aTruncateWith The truncation char.

Text()

IMPORT_C TPtrC Text ( ) const

Returns the original logically-ordered text supplied in the constructor.

TextDirectionality(const TDesC &, TBool *)

IMPORT_C TDirectionality TextDirectionality ( const TDesC & aText,
TBool * aFound = 0
) [static]

Reports the implicit directionality of a piece of text.

Parameters

const TDesC & aText The text to be examined.
TBool * aFound = 0 If non-null, returns ETrue if there were any strongly directional characters and EFalse if there were none. If a piece of text is spread over several descriptors, They need to be queried in sequence until one returns ETrue in aFound.

TruncationChar()

IMPORT_C TChar TruncationChar ( ) const

Returns the truncation character used.

WrapText(TInt, const CFont &, const MLineBreaker *, TInt)

IMPORT_C void WrapText ( TInt aWrappingWidth,
const CFont & aFont,
const MLineBreaker * aBreaker,
TInt aMaxLines
)

Prepares the visually-ordered text according to the wrapping width and font specified. Text cannot be drawn until this has been done.

Parameters

TInt aWrappingWidth The maximum width of the text in pixels. Note that this distance should be slightly less than the available width to allow for characters such as "W" which can have side-bearings that leak into the margins.
const CFont & aFont The font that will provide the character metrics.
const MLineBreaker * aBreaker An object for breaking the lines. May be NULL for default behaviour.
TInt aMaxLines Number of lines to restrict wrapping to. The truncation character will be used if the text is too long for this number of lines. The number of lines wrapped to may not be greater than the figure passed to NewL.

WrapText(TInt, const CFont &, const MLineBreaker *)

IMPORT_C void WrapText ( TInt aWrappingWidth,
const CFont & aFont,
const MLineBreaker * aBreaker = NULL
)

Prepares the visually-ordered text according to the wrapping width and font specified. Text cannot be drawn until this has been done.

Parameters

TInt aWrappingWidth The maximum width of the text in pixels. Note that this distance should be slightly less than the available width to allow for characters such as "W" which can have side-bearings that leak into the margins.
const CFont & aFont The font that will provide the character metrics.
const MLineBreaker * aBreaker = NULL An object for breaking the lines. May be NULL for default behaviour.

WrappingWidth()

IMPORT_C TInt WrappingWidth ( ) const

Returns the wrapping width previously supplied to WrapText.

Member Enumerations Documentation

Enum TDirectionality

Overall directionality of the text.

Enumerators

ELeftToRight = 0

Text reading begins on the left.

ERightToLeft = 1

Text reading begins on the right.

Enum TPanicCodes

Class specific panic codes This enum has been replaced by TBidiPanic.

Enumerators

EPanicRunArrayNull

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