GUI: Update listbox while editing text

I want a listbox to be dynamically updated when I change the input in an edit text box. The standard behavior of the GUI is to execute the callback function for the edit text box only after pressing enter or clicking outside the text box, but I want to find a way to execute the function while typing... this should not be so difficult right?

this is what I tried after searching the web:

function edit_text(hObject, eventdata, handles)
        addlistener(handles.edit_text,'String',@(hObject,eventdata)updateList(hObject,eventdata,handles));

and then I added the updateList function at the end of the GUI

    function updateList(hObject,eventdata,handles)

% code to set listboxInput

    set(handles.listbox_invoer,'String',listboxInput);

    % Update handles structure
    guidata(hObject, handles);

but I get the following error "The specified event is not supported by the object" referring to the line where I try to add the addlistener

Can someone help me on how to use this addlistener, the help documentation is not very explanatory...

[Ingrid]

It seems I was making it way to difficult... the addlistener function is not needed to solve this problem. If I add

set(handles.figure1,'KeyPressFcn',@myFunctionCustomKeyInput);
set(handles.edit1,'KeyPressFcn',@myFunctionCustomKeyInput);

to the OpeningFcn and then just add the function that updates my listbox to the end of myFunctionCustomKeyInput and it works perfectly! Hope this can inspire others...

[Ingrid]

the myFunctionCustomKeyInput requires the findjobj function to work as it needs to read in the text in the edit field even without it having being updated this works great in the matlab environment but fails when using the deploytool to create a standalone executable (which is my final goal) so I would like to ask again if anyone has another solution to this problem: how can you read in the text in the edit field without needing to press enter or click outside the textfield?