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TBidiText
Location:
BidiText.h
Link against: gdi.lib
class TBidiText;
Description
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.
Members
Defined in TBidiText:
Directionality(), DisplayText(), DrawText(), DrawText(), DrawText(), ELeftToRight, EPanicRunArrayNull, ERightToLeft, LineOfDisplayText(), MinimumSize(), NewL(), NewL(), NewL(), NumberOfLinesInDisplayText(), ScriptDirectionality(), SetText(), SetText(), SetTruncationChar(), TDirectionality, TPanicCodes, Text(), TextDirectionality(), TruncationChar(), WrapText(), WrapText(), WrappingWidth()
Construction and destruction
static IMPORT_C TBidiText *NewL(TInt aReservedMaxLength, TInt aMaxLines);
Description
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.
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|
Return value
static IMPORT_C TBidiText *NewL(const TDesC &aText, TInt aMaxLines);
Description
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.
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|
Return value
static IMPORT_C TBidiText *NewL(const TDesC &aText, TInt aMaxLines, TDirectionality aDirectionality);
Description
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.
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|
Return value
static IMPORT_C TDirectionality ScriptDirectionality(TLanguage aLanguage);
Description
Returns the directionality of a given language.
Parameters
Return value
static IMPORT_C TDirectionality TextDirectionality(const TDesC &aText, TBool *aFound=0);
Description
Reports the implicit directionality of a piece of text.
Parameters
const TDesC &aText |
The text to be examined.
|
TBool *aFound |
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.
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|
Return value
IMPORT_C TInt SetText(const TDesC &aText, RRunInfoArray &aRunInfoArray);
Description
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
Return value
TInt
|
The number of characters that didn't fit in the available buffer.
|
|
IMPORT_C TInt SetText(const TDesC &aText, TDirectionality aDirectionality, RRunInfoArray &aRunInfoArray);
Description
Sets the text of the bidirectional text with directionality determined by aDirectionality. Use this for text that has come
from user input.
Parameters
Return value
TInt
|
The number of characters that didn't fit in the available buffer.
|
|
Panic codes
Bidi |
EBidiPanic_RunArrayNull The call to RRunInfoArray::OpenL() has not been made prior to this call to TBidiText::SetText()
|
|
IMPORT_C void SetTruncationChar(TChar aTruncateWith);
Description
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.
|
|
IMPORT_C void WrapText(TInt aWrappingWidth, const CFont &aFont, const MLineBreaker *aBreaker, TInt aMaxLines);
Description
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.
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IMPORT_C void WrapText(TInt aWrappingWidth, const CFont &aFont, const MLineBreaker *aBreaker=0);
Description
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.
|
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IMPORT_C TSize MinimumSize(TInt aWrappingWidth, const CFont &aFont, TInt aLineGap, TInt aMaxLines=-1, const MLineBreaker *aBreaker=0)
const;
Description
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 |
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 |
An object for breaking the lines. May be NULL for default behaviour.
|
|
Return value
IMPORT_C TPtrC Text() const;
Description
Returns the original logically-ordered text supplied in the constructor.
Return value
TPtrC
|
The original logically-ordered text supplied in the constructor.
|
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IMPORT_C TPtrC DisplayText() const;
Description
Returns the text as prepared for display, provided that WrapText has been called. If WrapText has not been called, a panic
will result.
Return value
TPtrC
|
The text as prepared for display
|
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IMPORT_C TInt WrappingWidth() const;
Description
Returns the wrapping width previously supplied to WrapText.
Return value
IMPORT_C TDirectionality Directionality() const;
Description
Returns the directionality of the text.
Return value
IMPORT_C TChar TruncationChar() const;
Description
Returns the truncation character used.
Return value
TChar
|
The truncation character.
|
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NumberOfLinesInDisplayText()
IMPORT_C TInt NumberOfLinesInDisplayText() const;
Description
Reports the number of lines in the text to be drawn.
WrapText must have been called already.
Return value
TInt
|
The number of lines in the text which would be drawn by DrawText.
|
|
IMPORT_C TPtrC LineOfDisplayText(TInt aLine, TInt &aWidthInPixels) const;
Description
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 |
|
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Return value
TPtrC
|
The text as prepared for display.
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IMPORT_C void DrawText(CGraphicsContext &aGc, const TPoint &aLeft) const;
Description
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.
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IMPORT_C void DrawText(CGraphicsContext &aGc, const TPoint &aLeft, TInt aBaseLineSpacing, CGraphicsContext::TTextAlign aAlignment)
const;
Description
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.
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IMPORT_C void DrawText(CGraphicsContext &aGc, const TPoint &aLeft, TInt aBaseLineSpacing) const;
Description
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.
|
|
TDirectionality
Description
Overall directionality of the text.
TPanicCodes
Description
Class specific panic codes
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