Compiling to Target issue with Callbacks

[DMacD.1]

Code works fine in simulator but compilation to target (STM32756G-eval2).

Code:

// MainDisplayView.cpp
 
MainDisplayView::MainDisplayView(): 
    viewCallback(this, &MainDisplayView::buttonNavCallbackHandler),
    boxClickedCallback1(this, &MainDisplayView::boxClickedHandler1),
    boxClickedCallback2(this, &MainDisplayView::boxClickedHandler2)
{
    buttonLeft.setViewCallback(viewCallback);
    buttonRight.setViewCallback(viewCallback);
    overtempSetting1.setClickAction(boxClickedCallback1);
    durationSetting1.setClickAction(boxClickedCallback2);
}

Error:

 TouchGFX/gui/src/maindisplay_screen/MainDisplayView.cpp: In constructor 
          'MainDisplayView::MainDisplayView()':
 
TouchGFX/gui/src/maindisplay_screen/MainDisplayView.cpp:10:71: error: invalid use of non-static member function 'void MainDisplayView::buttonNavCallbackHandler(const buttonImportant&)'
                 boxClickedCallback2(this, &MainDisplayView::boxClickedHandler2)
                                                                               ^  
In file included from TouchGFX/gui/src/maindisplay_screen/MainDisplayView.cpp:1:0: TouchGFX/gui/include/gui/maindisplay_screen/MainDisplayView.hpp:60:10: note: declared here void 
       buttonNavCallbackHandler(const buttonImportant &b);
        ^~~~~~~~~~~~~~~~~~~~~~~~
        gcc/Makefile:320: recipe for target 'TouchGFX/build/STM32756G-EVAL/TouchGFX/gui/src/maindisplay_screen/MainDisplayView.o' failed
        

Particularly the error "invalid use of non-static member function" is what is puzzling me. My callbacks are setup how they should be. Any help would be appreciated.