sl@0: /*
sl@0: * Copyright (c) 1997-2009 Nokia Corporation and/or its subsidiary(-ies).
sl@0: * All rights reserved.
sl@0: * This component and the accompanying materials are made available
sl@0: * under the terms of "Eclipse Public License v1.0"
sl@0: * which accompanies this distribution, and is available
sl@0: * at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0: *
sl@0: * Initial Contributors:
sl@0: * Nokia Corporation - initial contribution.
sl@0: *
sl@0: * Contributors:
sl@0: *
sl@0: * Description: 
sl@0: *
sl@0: */
sl@0: 
sl@0: 
sl@0: #ifndef __TXTFMLYR_H__
sl@0: #define __TXTFMLYR_H__
sl@0: 
sl@0: #include <e32std.h>
sl@0: #include <e32base.h>
sl@0: #include <txtfmstm.h>
sl@0: #include <txtfrmat.h>
sl@0: 
sl@0: // forward declarations
sl@0: class CFormatStream;  
sl@0: class RReadStream;
sl@0: class RWriteStream;
sl@0: class TCharFormatX;
sl@0: 
sl@0: #ifndef SYMBIAN_ENABLE_SPLIT_HEADERS
sl@0: #include <txtfmlyr_internal.h>
sl@0: #endif
sl@0: 
sl@0: /** 
sl@0: Abstract base class for the paragraph and character format layers.
sl@0: 
sl@0: A format layer is a set of character or paragraph format attributes which 
sl@0: may own a pointer to another format layer. This pointer is called a based-on 
sl@0: link. The effective formatting of a text object may be built up from a chain 
sl@0: of format layers - the final layer in the chain has a NULL based-on link. 
sl@0: In case of conflict, attribute values set in upper layers (layers furthest 
sl@0: from the layer with the NULL based-on link) override those set in lower layers. 
sl@0: In rich text, additional formatting may be applied on top of these format 
sl@0: layers.
sl@0: 
sl@0: The system of based-on links is implemented by the CFormatLayer class. It 
sl@0: also implements persistence for chains of format layers.
sl@0: 
sl@0: When setting or sensing the attributes of a CParaFormatLayer or CCharFormatLayer, 
sl@0: a format mask and container are specified as parameters. The container has 
sl@0: data members for every format attribute, which may be set independently. When 
sl@0: setting the layer, the mask indicates the attributes which will be taken from 
sl@0: the container. Any attributes not specified in the mask will be taken from 
sl@0: the system-provided default values.
sl@0: 
sl@0: When sensing a layer, on return, the mask indicates which attributes have 
sl@0: been explicitly set in the layer, (i.e. not taken from the default values). 
sl@0: In addition, a layer's effective format may be sensed. In this case, no 
sl@0: mask is used because the format container will, on return, contain a value 
sl@0: for every attribute. 
sl@0: @publishedAll
sl@0: @released
sl@0: */
sl@0: class CFormatLayer : public CBase
sl@0: 	{
sl@0: public:
sl@0: 	//
sl@0: 	// Based-on link utilities
sl@0: 	IMPORT_C void Reset();  // Remove all contents of this layer in a leave safe manner.
sl@0: 	IMPORT_C void SetBase(const CFormatLayer* aBaseFormatLayer);  // Set this layer to be based on the specified layer.
sl@0: 	IMPORT_C const CFormatLayer* SenseBase()const;
sl@0: 	IMPORT_C TInt ChainCount()const;  // Returns the number of format layers in the chain, inclusive of itself.
sl@0: 	//
sl@0: 	// Persistence
sl@0: 	
sl@0: 
sl@0: 	/** Implementations of this function internalise the format layer but not its based-on 
sl@0: 	link from a read stream. The presence of this function means that the standard 
sl@0: 	templated operator>>() (defined in s32strm.h) is available to internalise 
sl@0: 	objects of the derived class. The internalised layer is set to be based on 
sl@0: 	the layer specified.
sl@0: 	
sl@0: 	@param aStream Stream from which the format layer should be internalised. 
sl@0: 	@param aBase The based-on link to assign to the layer. By default, NULL. */
sl@0: 	virtual void InternalizeL(RReadStream& aStream,const CFormatLayer* aBase=NULL)=0;
sl@0: 	
sl@0:  
sl@0: 	/** Implementations of this function externalise the format layer but not its based-on 
sl@0: 	link to a write stream. The presence of this function means that the standard 
sl@0: 	templatedoperator<<() (defined in s32strm.h) is available to externalise objects 
sl@0: 	of the derived class.
sl@0: 	
sl@0: 	@param aStream Stream to which the format layer should be externalised. */
sl@0: 	virtual void ExternalizeL(RWriteStream& aStream)const=0;
sl@0: 	//
sl@0: 	//	Restore a format chain where the end of the chain is based on aBase (where aBase may be null).
sl@0: 	IMPORT_C void InternalizeChainL(RReadStream& aStream,const CFormatLayer* aBase=NULL);
sl@0: 	//	Stores a format layer chain of length length-aExcludeCount (or by default the whole chain).
sl@0: 	IMPORT_C void ExternalizeChainL(RWriteStream& aStream,TInt aExcludeCount=0)const;
sl@0: 	/** Implementations of this function compare another format layer with the current 
sl@0: 	object. For the two layers to be equal, they must have the same contents and 
sl@0: 	(if the second parameter is ETrue), their based-on links must point to the 
sl@0: 	same format layer.
sl@0: 	
sl@0: 	@param aLayer The layer to compare to this format layer. 
sl@0: 	@param aCheckBasedOnLink If ETrue, both layers' based-on links must point to 
sl@0: 	the same format layer. If EFalse, the based-on links are not used in the comparison. 
sl@0: 	By default, ETrue. 
sl@0: 	@return ETrue if the two layers are identical, otherwise EFalse. */
sl@0: 	virtual TBool IsIdentical(CFormatLayer* aLayer,TBool aCheckBasedOnLink=ETrue)const=0;
sl@0: 	IMPORT_C TBool IsEmpty()const;
sl@0: 	void Swap(CFormatLayer& aLayer);
sl@0: private:
sl@0: 	CFormatLayer(const CFormatLayer& aFormatLayer);
sl@0: 	CFormatLayer& operator=(const CFormatLayer& aFormatLayer);
sl@0: 	virtual CFormatLayer* DoCloneL()const=0;
sl@0: protected:
sl@0: 	CFormatLayer();
sl@0: 	~CFormatLayer();
sl@0: 	virtual CFormatLayer* RestoreNewL(RReadStream& aStream)=0;
sl@0: 	void ExternalizeLayersRecurseL(RWriteStream& aStream,TInt aDescendantCount)const;
sl@0: 	TBool IsIdentical(const TUint8* aPtr,TInt aSize)const;
sl@0: 	const TUint8* Ptr(TInt& aSize)const;
sl@0: 	void CloneLayerL(CFormatLayer* aClone)const;
sl@0: protected:
sl@0: 	RFormatStream iStore;
sl@0: 	const CFormatLayer* iBasedOn;  // If non-null used to inherit format attributes from the lower layer.
sl@0: 	__DECLARE_TEST;
sl@0: 	};
sl@0: 
sl@0: 
sl@0: /** 
sl@0: A paragraph format layer. 
sl@0: 
sl@0: Has a pointer (stored in its base class CFormatLayer) to another paragraph 
sl@0: format layer which may be NULL. This pointer is referred to as the based-on 
sl@0: link. A paragraph format layer is owned by an instance of the CGlobalText 
sl@0: class and stores the object's global paragraph formatting. Implements persistence 
sl@0: and allows attributes to be set and sensed. 
sl@0: @publishedAll
sl@0: @released
sl@0: */
sl@0: class CParaFormatLayer : public CFormatLayer
sl@0: 	{
sl@0: public:
sl@0: 	IMPORT_C static CParaFormatLayer* NewL();
sl@0: 	IMPORT_C static CParaFormatLayer* NewL(const CParaFormat* aParaFormat,const TParaFormatMask& aMask);
sl@0: 	IMPORT_C static CParaFormatLayer* NewL(RReadStream& aStream);
sl@0: 	static CParaFormatLayer* NewL(const CParaFormatLayer* aLayer);
sl@0: 	static CParaFormatLayer* NewCopyBaseL(const CParaFormatLayer* aLayer);
sl@0: 	// Create a new instance, restoring it from the specified stream.
sl@0: 	// The based on link is NULL. Restores only one layer.
sl@0: 	//
sl@0: 	// Persistence
sl@0: 	IMPORT_C virtual void InternalizeL(RReadStream& aStream,const CFormatLayer* aBase=NULL);	
sl@0: 	IMPORT_C virtual void ExternalizeL(RWriteStream& aStream)const;
sl@0: 	//
sl@0: 	// Core methods
sl@0: 	IMPORT_C void SetL(const CParaFormat* aDesiredEffectiveFormat,const TParaFormatMask& aMask);
sl@0: 	IMPORT_C void SenseEffectiveL(CParaFormat* aParaFormat,CParaFormat::TParaFormatGetMode aMode=CParaFormat::EAllAttributes)const;
sl@0: 	IMPORT_C void SenseL(CParaFormat* aParaFormat,TParaFormatMask& aMask,CParaFormat::TParaFormatGetMode aMode=CParaFormat::EAllAttributes)const;
sl@0: 	//
sl@0: 	// Utilities
sl@0: 	inline CParaFormatLayer* CloneL()const;
sl@0: 	IMPORT_C TBool IsIdenticalL(const CParaFormat* aParaFormat,const TParaFormatMask& aMask)const;
sl@0: 	IMPORT_C virtual TBool IsIdentical(CFormatLayer* aLayer,TBool aCheckBasedOnLink=ETrue)const;
sl@0: 	IMPORT_C virtual TUid Type()const;
sl@0: 	IMPORT_C const TUint8* Ptr(TInt& aSize)const;
sl@0: private:
sl@0: 	//
sl@0: 	// No implementation provided
sl@0: 	CParaFormatLayer(const CParaFormatLayer& aParaFormatLayer);
sl@0: 	CParaFormatLayer& operator=(const CParaFormatLayer& aParaFormatLayer);
sl@0: 	IMPORT_C virtual CFormatLayer* DoCloneL()const;
sl@0: 	void FillParaFormatL(CParaFormat* aParaFormat,TParaFormatMask& aMask,CParaFormat::TParaFormatGetMode aMode)const;
sl@0: 	void CleanupEffectiveFormat(CParaFormat* aParaFormat,TParaFormatMask aMask)const;
sl@0: 	void CleanupBorders(CParaFormat* aParaFormat)const;
sl@0: protected:
sl@0: 	CParaFormatLayer();
sl@0: 	virtual CFormatLayer* RestoreNewL(RReadStream& aStream);
sl@0: 	};
sl@0: 
sl@0: /** 
sl@0: Character format layer.
sl@0: 
sl@0: Uses a pointer (stored in its base class CFormatLayer) to another character 
sl@0: format layer which may be NULL. This pointer is referred to as the based-on 
sl@0: link. A character format layer is owned by an instance of the CGlobalText 
sl@0: class and stores the object's global character formatting. Implements persistence 
sl@0: and allows attributes to be set and sensed. 
sl@0: @publishedAll
sl@0: @released
sl@0: */
sl@0: class CCharFormatLayer : public CFormatLayer
sl@0: 	{
sl@0: public:
sl@0: 	IMPORT_C static CCharFormatLayer* NewL();
sl@0: 	IMPORT_C static CCharFormatLayer* NewL(const TCharFormat& aFormat,const TCharFormatMask& aMask);
sl@0: 	IMPORT_C static CCharFormatLayer* NewL(RReadStream& aStream);
sl@0: 	IMPORT_C virtual void InternalizeL(RReadStream& aStream,const CFormatLayer* aBase=NULL);	
sl@0: 	IMPORT_C virtual void ExternalizeL(RWriteStream& aStream)const;
sl@0: 	IMPORT_C void SetL(const TCharFormat& aCharFormat,const TCharFormatMask& aMask);
sl@0: 	IMPORT_C void SenseEffective(TCharFormat& aCharFormat)const;
sl@0: 	IMPORT_C void Sense(TCharFormat& aCharFormat,TCharFormatMask& aMask)const;
sl@0: 	inline CCharFormatLayer* CloneL()const;
sl@0: 	IMPORT_C virtual TBool IsIdentical(CFormatLayer* aLayer,TBool aCheckBasedOnLink=ETrue)const;
sl@0: 	IMPORT_C TBool IsIdentical(const TCharFormat& aCharFormat,const TCharFormatMask& aMask)const;
sl@0: 	IMPORT_C const TUint8* Ptr(TInt& aSize)const;
sl@0: 
sl@0: 	// non-exported public functions
sl@0: 	static CCharFormatLayer* NewL(const CCharFormatLayer* aLayer);
sl@0: 	static CCharFormatLayer* NewCopyBaseL(const CCharFormatLayer* aLayer);
sl@0: 	static CCharFormatLayer* NewL(const TCharFormatX& aFormat,const TCharFormatXMask& aMask);
sl@0: 	void SetL(const TCharFormatX& aCharFormat,const TCharFormatXMask& aMask);
sl@0: 	void SenseEffective(TCharFormatX& aCharFormat)const;
sl@0: 	void Sense(TCharFormatX& aCharFormat,TCharFormatXMask& aMask) const;
sl@0: 	
sl@0: private:
sl@0: 	CCharFormatLayer();
sl@0: 	virtual CFormatLayer* RestoreNewL(RReadStream& aStream);
sl@0: 	virtual void FillCharFormat(TCharFormatX& aCharFormat,TCharFormatXMask& aMask)const;
sl@0: 	IMPORT_C virtual CFormatLayer* DoCloneL()const;
sl@0: 	};
sl@0: 
sl@0: 
sl@0: #include <txtfmlyr.inl>
sl@0: 
sl@0: 
sl@0: #endif