Derive a class from the MCoeView class


Derive a class from the MCoeView class and provide the definition for each of the following functions:

  • TVwsViewId ViewId() const

    This function defines the unique identifier of the view within the given application.

  • void ViewActivatedL(const TVwsViewId& aPrevViewId,TUid aCustomMessageId,const TDesC8& aCustomMessage)

    This is the function is called by the operating system when a view is activated. The call gets several arguments: the view ID of the previous view that was displayed (in case a switch back to it is desired), and the identifier and text of a message that comes from the process that is activating the view. This message can convey specialized information, such as information on what to display, from the activating process.

  • void ViewDeactivated()

    This function is called by the operating system when a view is deactivated.

  • TVwsViewIdAndMessage ViewScreenDeviceChangedL()

    This function has a default implementation. It handles a change to the screen device returning the value of the TVwsViewIdAndMessage object. By default, returns the ID of the active view.

    Cone provides a default screen device change handler CCoeScreenDeviceChangeDefaultHandler. CCoeScreenDeviceChangeDefaultHandler handles any screen device changes that occur while a view is active. It is used to activate a default view when a screen flip (changing the screen orientation, for example, landscape to portrait) occurs, if the currently active view does not implement MCoeView::ViewScreenDeviceChangedL().

The following code snippet shows deriving a class from MCoeView and implementing the required functions:

class CNewView : public MCoeView
        CNewView( const TVwsViewId& aViewId, CCoeAppUi& aAppUi );
        void ConstructL();
        // From MCoeView class
        void ViewActivatedL( const TVwsViewId& aPrevViewId, 
                             TUid aCustomMessageId, 
                             const TDesC8& aCustomMessage );    
        void ViewDeactivated();
        TVwsViewIdAndMessage ViewScreenDeviceChangedL();
        void ViewConstructL();
        CCoeAppUi& iCCoeAppUi;
        TVwsViewId& iViewId;