how KeyPressFcn function works?

hi everyone, i have an edit text, pressing backspace, only when edit text become empty i want to set a string into a static text. how can i do? something like:

function edit_T KeyPressFcn(hObject, eventdata, handles)
if "press backspace" && "edit_T is empty"
       set(handles.static_text,'String',string);

Answer 1

[Walter Roberson]

http://www.mathworks.com/help/matlab/ref/uicontrol-properties.html#property_keypressfcn

"If you specify this property as a function handle (or cell array containing a function handle), MATLAB passes an object containing callback data as the second argument to the callback function. This object contains the properties described in the following table."

For backspace, the 'key' property will contain 'backspace'

[Luke Perry]

Updated Link: https://www.mathworks.com/help/matlab/ref/matlab.ui.figure-properties.html#buiwuyk-1-KeyPressFcn