Converting a COC to an MFD

This tutorial will show you how to convert a normal COC to a Multi-Function Display (MFD) COC.

• In the wizard, add an attribute change callback for ATT_CURRENT_DISPLAYED_SYSTEM. Since this attribute is owned by the base content LOC GeneralAvionics, your base object must have this LOC.
  
• In RegisterToAttributeChanges(), replace ATT2_STRING_ALL_KEYS_LISTENER with _sParentGaugeNameW. Now the component is only registered to the 2-parameter attribute ATT_CURRENT_DISPLAYED_SYSTEM for its parent gauge.
  
• In the start() function, replace the line of code between the //DLC_ATTRIBUTECHANGE_CALLS tags with the line below:
  

CBFuncAttChangeCurrentDisplayedSystem(GET_ENTITY_ATT_INDEX(_pOwnerEntity, _T("ATT_CURRENT_DISPLAYED_SYSTEM")), _sParentGaugeNameW);

• In the callback function for ATT_CURRENT_DISPLAYED_SYSTEM, add code to unregister mouse regions and hide the page if the current displayed system isn't the name of this MFD page. Follow the example below.
  

if (AttCurrentDisplayedSystem != _T("NAME"))
{
   hideDlc();
   unRegisterAllMouseRegionsEvents();
}
else
{
   showDlc();
   registerAllMouseRegionsEvents();
}

• Use the wizard to add an input event called INPUT_CHANGE_TO_NAME. In the registerToInputDevices() function, edit the code so that the input event has the parent gauge name appended to it. Follow the example below.
  

wstring inputStr = wstring(L"INPUT_CHANGE_TO_NAME") + _sParentGaugeNameW;
REGISTER_INPUT_EVENT_MULTIPLE(_pOwnerEntity, this, &LOC_Class::CBFuncInputEventChangeToName, LOC_Class, inputStr.c_str(), _T("Change to NAME MFD page."));

• In the CBFuncInputEventChangeToName(…) function, add the following code:
  

CALL_ENTITY_ACTION_2(_pOwnerEntity, _T("ACTION_SET_CURRENT_DISPLAYED_SYSTEM"), _sParentGaugeNameW, _T("NAME"));

• In start(), comment out showDlc() and registerAllMouseRegionsEvents().
  
• Build and analyze your component. The component will now display only if ATT_CURRENT_DISPLAYED_SYSTEM is equal to NAME.