textrendering/textformatting/inc/EditorUndo.h
changeset 0 1fb32624e06b
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/textrendering/textformatting/inc/EditorUndo.h	Tue Feb 02 02:02:46 2010 +0200
@@ -0,0 +1,167 @@
+/*
+* Copyright (c) 2000-2009 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 EDITORUNDO_H_
+#define EDITORUNDO_H_
+
+#include "unified_editor.h"
+
+namespace UndoSystem
+/**
+@internalTechnology
+*/
+{
+class CCommandManager;
+class MNotUndoableGatekeeper;
+}
+
+class CEditorCommandFactory;
+
+/**
+MUnifiedEditor decorator that adds undo functionality.
+It passes commands transparently to the editor it is constructed upon, while
+storing the operations so that they can be undone and redone. Calling a
+non-const method of MUnifiedEditor wipes all 'Redo' operations.
+The undo and redo operations are only guaranteed to be accurate if the
+underlying editor satisfies certain conditions.
+
+@since App-frameworks6.1
+@internalAll
+*/
+class CEditorWithUndo : public CBase,
+	public MUnifiedEditor,
+	private MUnifiedEditor::MStyleSupport,
+	private MUnifiedEditor::MPictureSupport,
+	private MUnifiedEditor::MClipboardSupport
+
+	{
+public:
+	~CEditorWithUndo();
+
+	/**
+	 * Creates a CEditorWithUndo. It does not own the aEditor.
+	 */
+	IMPORT_C static CEditorWithUndo* NewL(MUnifiedEditor& aEditor);
+	/**
+	 * Creates a CEditorWithUndo, using the aSharedUndoSystem. This allows
+	 * many objects to stay in synchronization when each is accessed
+	 * seperately.
+	 * The aEditor is not owned.
+	 */
+	IMPORT_C static CEditorWithUndo* NewL(MUnifiedEditor& aEditor,
+		UndoSystem::CCommandManager* aSharedUndoSystem);
+	/**
+	 * Undoes one operation or batch of operations. If one operation in the
+	 * middle of a batch leaves, this function will leave, but the underlying
+	 * editor will not necessarily be in the same state as it was in before
+	 * the call. However, all operations will still be stored, and so the
+	 * previous state is still recoverable with a call to RedoL() or a
+	 * further call to UndoL will complete the operation (resource acquisition
+	 * permitting).
+	 */
+	IMPORT_C void UndoL();
+	/**
+	 * Redoes one operation or batch of operations. If one operation in the
+	 * middle of a batch leaves, this function will leave, but the underlying
+	 * editor will not necessarily be in the same state as it was in before
+	 * the call. However, all operations will still be stored, and so the
+	 * previous state is still recoverable with a call to UndoL() or a
+	 * further call to RedoL will complete the operation (resource acquisition
+	 * permitting).
+	 */
+	IMPORT_C void RedoL();
+	/**
+	 * Returns ETrue iff UndoL() would have an effect
+	 */
+	IMPORT_C TBool CanUndo() const;
+	/**
+	 * Returns ETrue iff RedoL() would have an effect
+	 */
+	IMPORT_C TBool CanRedo() const;
+	/**
+	 * Wipes all undo and redo operations
+	 */
+	IMPORT_C void ResetUndo();
+	/**
+	 * Sets limits on the 'undo depth'. This is the numbet of times that
+	 * successive calls to UndoL() have an effect. When a depth of
+	 * aMaxItems is reached, the undo depth is reset to aMinItems.
+	 */
+	IMPORT_C void SetMaxItems(TInt aMaxItems);
+	/**
+	 * Sets a gatekeper for the undo system. This will be called whenever an
+	 * operation is attempted that cannot be undone for any reason.
+	 * The gatekeeper therefore has an oportunity to suppress execution and
+	 * keep the current undo operations stored.
+	 * NULL may be passed to restore default behaviour.
+	 * Returns the old gatekeeper.
+	 */
+	IMPORT_C UndoSystem::MNotUndoableGatekeeper*
+		SetGatekeeper(UndoSystem::MNotUndoableGatekeeper*);
+
+	// From MUnifiedEditor
+	MTmOptionalInterface* Interface(TUint aId);
+	void InsertTextL(TInt aPos, const TDesC& aText, const TDesC* aStyle,
+		const TTmCharFormatLayer*, const RTmParFormatLayer*);
+	void DeleteTextL(TInt aPos,TInt aLength);
+	void SetBaseFormatL(const TTmCharFormat&, const RTmParFormat&);
+	void SetCharFormatL(TInt aPos, TInt aLength, const TTmCharFormatLayer&);
+	void SetParFormatL(TInt aPos, TInt aLength, const RTmParFormatLayer&);
+	void DeleteCharFormatL(TInt aPos, TInt aLength);
+	void DeleteParFormatL(TInt aPos, TInt aLength);
+	TInt DocumentLength() const;
+	void GetText(TInt aPos, TPtrC& aText) const;
+	void GetBaseFormatL(TTmCharFormat&, RTmParFormat&) const;
+	void GetCharFormat(TInt aPos, TFormatLevel aLevel,
+		TTmCharFormatLayer& aFormat,TInt& aRunLength) const;
+	void GetParFormatL(TInt aPos, TFormatLevel aLevel,
+		RTmParFormatLayer& aFormat, TInt& aRunLength) const;
+
+private:
+	// from MStyleSupport
+	TInt CreateStyleL(const RTmStyle&);
+	TInt ChangeStyleL(const RTmStyle&);
+	TInt SetStyleL(TInt aPos, TInt aLength, const TDesC&);
+	TInt RenameStyleL(const TDesC& aOldName, const TDesC& aNewName);
+	TInt DeleteStyleL(const TDesC& aName);
+	TInt StyleCount() const;
+	void GetStyle(TInt aPos, TPtrC& aName, TInt& aRunLength) const;
+	TInt GetStyleByNameL(const TDesC& aName, RTmStyle&) const;
+	TInt GetStyleByIndexL(TInt aIndex, RTmStyle&) const;
+
+	// from MPictureSupport
+	void InsertPictureL(TInt aPos, const TPictureHeader&);
+	void DropPictureL(TInt aPos);
+	void Picture(TInt aPos, TPictureHeader&) const;
+
+	// from MClipboardSupport
+	void CopyToStoreL(CStreamStore& aStore, CStreamDictionary& aDictionary,
+		TInt aPos, TInt aLength) const;
+	void PasteFromStoreL(const CStreamStore& aStore,
+		const CStreamDictionary& aDictionary, TInt aPos);
+
+	CEditorWithUndo();
+	void ConstructL(MUnifiedEditor& aEditorBasedOn,
+		UndoSystem::CCommandManager* aSharedUndoSystem);
+
+	CEditorCommandFactory*			iFactory;
+	MUnifiedEditor*						iBaseEditor;
+	UndoSystem::CCommandManager*	iCommandManager;
+	};
+
+#endif	// EDITORUNDO_H_