/*

* Copyright (c) 2002-2004 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of the License "Symbian Foundation License v1.0" to Symbian Foundation members and "Symbian Foundation End User License Agreement v1.0" to non-members

* which accompanies this distribution, and is available

* at the URL "http://www.symbianfoundation.org/legal/licencesv10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description: 

* 	  Support for Form component. Also has CAknDialog which specialized 

*     CEikDialog (adds menu capability) Note that most support for Avkon

*     Forms is contained within CEikDialog.

*

*

*/

#ifndef __AKNFORM_H__

#define __AKNFORM_H__

// INCLUDES

#include <aknDialog.h>

// CLASS DECLARATION

class CEikMenuBar ;

/**

* Forms are special types of dialogs. The item layout and functionality can

* differ between the two states. In the view state, the fields are not 

* editable. It looks and acts like a listbox. The listbox focus can be moved

* and items can be selected.

*

*  @since Series 60 0.9

*/

class CAknForm : public CAknDialog

	{

public:

	/**

	* Base class default constructor.

	*/

	IMPORT_C CAknForm();

	/**

    * Perform the second phase construction of a object. If a leave occurs

    * the framework generates a Symbian Leave code.

    * @param aMenuResource The menu resource to be used for the form.

    */

	IMPORT_C void ConstructL( TInt aMenuBarId=0 );

	/**

	* Destructor.

	*/

	IMPORT_C ~CAknForm();

    /**

    * Function from @c MEikMenuObserver. The framework 

    * calls this function. It removes the unused default form options. If a 

    * leave occurs the framework generates a Symbian Leave code. 

    * @param aResourceId The ID of the menu pane.

    * @param aMenuPane The menu pane itself.

    */

	IMPORT_C virtual void DynInitMenuPaneL( TInt aResourceId, CEikMenuPane* aMenuPane );

    /**

    * Function from @c MEikCommandObserver. Handle user menu commands. If a

    * leave occurs the framework generates a Symbian Leave code.

    * @param aCommandId The command identifier to process.

    */ 

	IMPORT_C virtual void ProcessCommandL( TInt aCommandId );

protected:

	/**

	* Function from @c CEikDialog. Called by framework when the softkey is 

	* pressed. Use this to pop up the options menu or close the dialog. Will

	* call c@ SaveFormDataL() before closing if data has been edited. Will 

	* NOT permit exit if attempt to save data fails. If a leave occurs the 

	* framework generates a Symbian Leave code.

 	* @param aButtonId Translates the button presses into commands ID.

 	* @return @c ETrue if the dialog should exit, and @c EFalse if it should

 	* not. 

	*/ 

	IMPORT_C virtual TBool OkToExitL( TInt aButtonId );

	/**

	* Function from @c CEikDialog and thence from c@ MEikDialogPageObserver.

	* This funtion should be implemented to prepare for focus transition from

	* the current line. If deleting then this routine must not do anything (the

	* default tries to access the control which has just been deleted). If a

	* leave occurs the framework generates a Symbian Leave code.

	*/

	IMPORT_C virtual void PrepareForFocusTransitionL();

public:

	/**

	* Function from @c CCoeControl handles a change to the control's resources

	* of type aType which are shared across the environment, e.g. colors or 

	* fonts.

	* @param aType. A message UID value.

	* @since Series 60 2.0

	*/

	IMPORT_C void HandleResourceChange(TInt aType);

        /**

         * From CCoeControl.     

         * Handles pointer events

         * @param aPointerEvent     The pointer event.

         */

    	IMPORT_C void HandlePointerEventL(const TPointerEvent& aPointerEvent);

protected:

	/**

	* This routine should be re-implemented by the client to save the contents

	* of the form. The re-implementation can call this function to display the 

	* 'Saved' dialog @c CAknForm::SaveFormDataL().

	* @return @c ETrue if the editable state can be left. The return value should

	* reflect whether or not the form is to leave the editable state. A real 

	* system problem saving should generate a Symbian Leave code.

	*/

	IMPORT_C virtual TBool SaveFormDataL(); 

	/**

	* This routine should be implemented by the client for dealing with the 

	* occasion of a change from edit->view mode but the user does not wish to 

	* save the changes. A typical implementation would set the controls back 

	* to their old values. If a leave occurs the framework generates a 

	* Symbian Leave code.

	*/

	IMPORT_C virtual void DoNotSaveFormDataL(); 

	/**

	* This routine may be overridden. Default displays 'Save Changes Dialog 

	* Yes/No'. Data validation may occur here as an alternative to overriding

	* @c OkToExit(). Re-implementation may put data validation here (as an 

	* alternative to over-riding @c OkToExit() - which is a more complicated 

	* method). Note that this routine does not perform the changes itself. If 

	* the leave occurs the framework generates a Symbian Leave code.

	* @return @c ETrue if changes are requested to be saved and then are 

	* successfully saved. Save of data is not performed here but in 

	* @c SaveFormDataL().

    */

	IMPORT_C virtual TBool QuerySaveChangesL();

	/**

 	* This routine may be overridden. Default displays old label as caption and

 	* editor for new one. Uses customised dialog.If a leave occurs the 

 	* framework generates a Symbian Leave code.

 	*/

	IMPORT_C virtual void EditCurrentLabelL();

	/**

 	* This routine may be overridden. Default displays "Delete item? Yes/No"

 	* Deletes item on return from the dialog before returning. If a leave occurs

 	* the framework generates a Symbian Leave code.

 	*/	

	IMPORT_C virtual void DeleteCurrentItemL();

	/**

 	* This routine may be overridden. Implementation is missing in this class.

 	*/	

	IMPORT_C virtual void AddItemL();

	/**

	* Sets changes pending.

	* @param aChangesPending @c ETrue if changes are pending. Else @cEFalse. 

	*/	

	IMPORT_C void SetChangesPending(TBool aChangesPending);

	/**

	* Function from @c CEikdialog. This function is called by the EIKON 

	* dialog framework just before the dialog is activated, after it has 

	* called @c PreLayoutDynInitL() and the dialog has been sized. If a  

	* leave occurs the framework generates a Symbian Leave code.

	*/	

	IMPORT_C void PostLayoutDynInitL();

	/**

	* Overridden, so that the form can tell if a line's state has changed.

	* This is used to decide when to save changes. If a leave occurs the

	* framework generates a Symbian Leave code.

	* @param aControlId. Control id. 

	*/	

	IMPORT_C void HandleControlStateChangeL(TInt aControlId);

	/** 

	* This is added, so that anyone adding lines either in @c PreLayoutDynInit()

	* or @c SetInitialCurrentLine() should have the lines in a consistent state.

	*/	

	IMPORT_C void SetInitialCurrentLine();

	/** 

	* Required by @c OkToExit().

	* @return @c ETrue if unsave editing, and @c EFalse if it 

	* should not.

	*/

	IMPORT_C TBool UnsavedEdit() const;

	/** 

	* Required by @c PrepareForFocusTransitionL().

	* @return @c ETrue if deleting, and @c EFalse if it 

	* should not.

	*/	

	IMPORT_C TBool Deleting() const;

enum TFlags

	{

	/** Flag for deleting item. */

	EDeleting = 0x1, // Form flag enum

	/** Flag for unsave editing item. */

	EUnsavedEdit = 0x2 // Form flag enum

	};

	/**

	* Set the form flag indicated.

	* @param aFlagPattern Pattern of bits to set or clear.

	* @param aSetTheFlag If @c ETrue, sets the pattern; if @c EFalse, clear the 

	* pattern.

	*/

	IMPORT_C void SetFormFlag( TFlags aFlagPattern, TBool aSetTheFlag );

private: 

    /**

    * From CAknControl

    */

    IMPORT_C void* ExtensionInterface( TUid aInterface );

private: 

	IMPORT_C virtual void CEikDialog_Reserved_1();

	IMPORT_C virtual void CEikDialog_Reserved_2();	

private: 

	IMPORT_C virtual void CAknDialog_Reserved();

private:// new function  

	IMPORT_C virtual void CAknForm_Reserved();

private: // helpers

	void DoLayout();

private :

	TInt iMenuBarId ;  // resource ID

	TInt iFlags ;

	TInt iWsBufferRequestID;

	} ;

#endif	// __AKNFORM_H__