/*

 * 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 "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: 

 * 	  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__