graphicsdeviceinterface/gdi/inc/LineBreak.h
changeset 0 5d03bc08d59c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graphicsdeviceinterface/gdi/inc/LineBreak.h	Tue Feb 02 01:47:50 2010 +0200
@@ -0,0 +1,229 @@
+// Copyright (c) 2002-2009 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:
+//
+
+#ifndef LINEBREAK_H_
+#define LINEBREAK_H_
+
+#include <e32def.h>
+class MContingentLineBreaker;
+class MContingentLineBreakerL;
+class TDesC16;
+class TUid;
+
+
+/**
+ This enumeration holds the possible panic codes that may be raised
+ by the LineBreak API on detecting an unrecoverable error.
+@publishedAll
+@released
+*/
+enum TLineBreakPanic
+	{
+	/** Not used */
+	ELineBreakPanic_Unknown				= 0,
+	/** Internal error, error found in data table */
+	ELineBreakPanic_BadTable			= 1,
+	/** One or more of the input parameters to the interface were invalid */
+	ELineBreakPanic_InvalidInputParam	= 2,
+	/** Raised when an output parameter breaks an API condition */
+	ELineBreakPanic_InvalidOutputParam	= 3,
+	};
+
+
+
+class MLineBreaker
+/**
+Customizes the Unicode line-breaking algorithm. 
+@publishedAll
+@released
+*/
+	{
+public:
+	/** The Unicode line breaking classes; see Unicode Technical Report 14.
+	Not a named enumerated type, so that overriding classes may add new
+	line breaking classes freely.
+	The description of each constant gives the name of the line-breaking
+	class, an example and a brief, imprecise description of the default
+	behaviour of characters of that class.	 */
+	enum
+		{
+		/** Opening Punctuation (e.g. '['). Breaking after prohibited. */
+		EOpLineBreakClass,
+		/** Closing Punctuation (e.g. ']'). Breaking before prohibited. */
+		EClLineBreakClass,
+		/** Ambiguous Quotes (e.g. '"'). Breaking before and after prohibited. */
+		EQuLineBreakClass,
+		/** Glue (e.g. Non-breaking space). Breaking before and after prohibited
+		unless spaces are present. */
+		EGlLineBreakClass,
+		/** Non-Starter (e.g. small Japanese kana). Breaking before prohibited
+		if no spaces present. */
+		ENsLineBreakClass,
+		/** Exclamation or Interrogation (e.g. '?'). Like closing punctuation
+		except before Postfix or Non-starter. */
+		EExLineBreakClass,
+		/** Symbol (e.g. '/'. Like Alphabetic, but allows breaking before
+		Alphabetic. */
+		ESyLineBreakClass,
+		/** Numeric Infix Separator (e.g. ','). Forbids breaking after any and before
+		Numeric. */
+		EIsLineBreakClass,
+		/** Numeric Prefix (e.g. '$'). Forbids breaking before Numeric. */
+		EPrLineBreakClass,
+		/** Numeric Postfix (e.g. '%'). Forbids breaking after Numeric. */
+		EPoLineBreakClass,
+		/** Numeric (e.g. '1'). */
+		ENuLineBreakClass,
+		/** Alphabetic (e.g. 'a'). */
+		EAlLineBreakClass,
+		/** Ideographic (e.g. Japanese Kanji). Generally break before or after */
+		EIdLineBreakClass,
+		/** Inseparable (e.g. ellipsis). Forbid breaks between Inseparables. */
+		EInLineBreakClass,
+		/** Hyphen (e.g. '-'). Allows a break after except before Numeric. */
+		EHyLineBreakClass,
+		/** Break After. Generally allow a break after. Breaking between Break
+		Afters not separated by spaces is prohibited. */
+		EBaLineBreakClass,
+		/** Break Before. Generally allow a break before. Breaking between Break
+		Befores not separated by spaces is prohibited. */
+		EBbLineBreakClass,
+		/** Break Before and After. Generally allow a break before or after.
+		Breaking between Break Before and Afters is prohibited, even if spaces
+		are present. */
+		EB2LineBreakClass,
+		/** Zero-Width Space. Allow a break. */
+		EZwLineBreakClass,
+		/** Combining Mark. Takes on the class of its base class. */
+		ECmLineBreakClass,
+		/** Mandatory Break. */
+		EBkLineBreakClass,
+		/** Carriage Return. Break after unless part of a CRLF pair. */
+		ECrLineBreakClass,
+		/** Line Feed. Break after. */
+		ELfLineBreakClass,
+		/** Surrogate. Half of a surrogate pair. */
+		ESgLineBreakClass,
+		/** Contingent Break (e.g. embedded pictures). Uses external
+		information */
+		ECbLineBreakClass,
+
+		/** Space. Intervening characters of class Space are indicated by
+		aHaveSpaces in LineBreakPossible. */
+		ESpLineBreakClass, 
+
+		/** Complex Context (e.g. Thai). Runs of Complex Context are passed to
+		GetLineBreakInContext. */
+		ESaLineBreakClass,
+
+		/** Ambiguous. Characters of ambiguous East Asian width are treated
+		as Alphabetic, unless they are resolved as being "Wide", in which case
+		they are treated as Ideographic. */
+		EAiLineBreakClass,
+
+		/** The Xx class is used when the class is unknown; e.g.; outside the provided context. */
+		EXxLineBreakClass,
+
+		/** The number of Unicode line break classes. */
+		ELineBreakClasses
+		};
+
+	IMPORT_C virtual TUint LineBreakClass(TUint aCode,
+		TUint& aRangeStart, TUint& aRangeEnd) const;
+	IMPORT_C virtual TBool LineBreakPossible(TUint aPrevClass, TUint aNextClass,
+		TBool aHaveSpaces) const;
+	IMPORT_C virtual TBool GetLineBreakInContext(const TDesC16& aText,
+		TInt aMinBreakPos, TInt aMaxBreakPos, TBool aForwards,
+		TInt& aBreakPos) const;
+	IMPORT_C virtual TBool IsHangingCharacter(TUint aChar) const;
+	IMPORT_C TBool GetLineBreak(const TDesC16& aText,
+		TInt aMinBreakPos, TInt aMaxBreakPos, TBool aForwards,
+		MContingentLineBreaker* aCbDelegate,
+		TInt& aBreakPos, TInt& aBreakPosAfterSpaces) const;
+	IMPORT_C TBool GetLineBreakL(const TDesC16& aText,
+		TInt aMinBreakPos, TInt aMaxBreakPos, TBool aForwards,
+		MContingentLineBreakerL* aCbDelegate,
+		TInt& aBreakPos, TInt& aBreakPosAfterSpaces) const;
+	IMPORT_C virtual void* ExtendedInterface(TUid& aUid) const;
+	};
+
+
+class MContingentLineBreaker
+/**
+Used to determine the line breaks around pictures and other characters with 
+the CB (contingent line break) class in situations where this operation cannot 
+leave. 
+@publishedAll
+@released
+*/
+	{
+public:
+	/** Determines if a break is legal before the picture at aTextPosition. 
+	
+	@param aTextPosition The position of a character of line breaking class ECbLineBreakClass 
+	in the text as supplied to MLineBreaker::GetLineBreak(), which may refer to 
+	a picture.
+	@param aPrecedingClass The class of the character preceding aTextPosition.
+	@param aHasSpaces ETrue if spaces separate the preceding class from this.
+	@return ETrue if a line break is legal here. */
+	virtual TBool IsLegalBreakBefore(TInt aTextPosition, TInt aPrecedingClass,
+		TBool aHasSpaces) = 0;
+	/** Determines if a break is legal after the picture at aTextPosition. 
+	
+	@param aTextPosition The position of a character of line breaking class ECbLineBreakClass 
+	in the text as supplied to MLineBreaker::GetLineBreak, which may refer to 
+	a picture.
+	@param aFollowingClass The class of the character immediately following aTextPosition.
+	@param aHasSpaces ETrue if spaces separate the following class from this.
+	@return ETrue if a line break is legal here. */
+	virtual TBool IsLegalBreakAfter(TInt aTextPosition, TInt aFollowingClass,
+		TBool aHasSpaces) = 0;
+	};
+
+
+
+class MContingentLineBreakerL
+/**
+Used to determine the line breaks around pictures and other characters with 
+the CB (contingent line break) class in situations where this operation may 
+leave. 
+@publishedAll
+@released
+*/
+	{
+public:
+	/** Determines if a break is legal before the picture at aTextPosition. 
+	
+	@param aTextPosition The position of a character of line breaking class ECbLineBreakClass 
+	in the text as supplied to MLineBreaker::GetLineBreak(), which may refer to 
+	a picture.
+	@param aPrecedingClass The class of the character preceding aTextPosition.
+	@param aHasSpaces ETrue if spaces separate the preceding class from this.
+	@return ETrue if a line break is legal here. */
+	virtual TBool IsLegalBreakBeforeL(TInt aTextPosition, TInt aPrecedingClass,
+		TBool aHasSpaces) = 0;
+	/** Determines if a break is legal after the picture at aTextPosition. 
+	
+	@param aTextPosition The position of a character of line breaking class ECbLineBreakClass 
+	in the text as supplied to MLineBreaker::GetLineBreak(), which may refer to 
+	a picture.
+	@param aFollowingClass The class of the character immediately following aTextPosition.
+	@param aHasSpaces ETrue if spaces separate the preceding class from this.
+	@return ETrue if a line break is legal here. */
+	virtual TBool IsLegalBreakAfterL(TInt aTextPosition, TInt aFollowingClass,
+		TBool aHasSpaces) = 0;
+	};
+
+#endif