求教同一个GUI中不同function间的调用

function popupmenu2_Callback(hObject, eventdata, handles)

val1=get(hObject,'Value');
switch val1
    case 1
        handles.rv_idx = 0;
    case 2
        handles.rv_idx = 1;
    case 3
        handles.rv_idx = 2;
    case 4
        handles.rv_idx = 3;
end
guidata(hObject, handles);


function edit3_Callback(hObject, eventdata, handles)

val6 = str2double(get(hObject, 'String'));
handles.RBNum= val6;
guidata(hObject,handles)


function start_simulation_Callback(hObject, eventdata, handles)
flagtime = top_GUI(handles.RBNum,handles.rv_idx);


就是前两个控件分别得到handles.RBNum和handles.rv_idx，然后想把这两个参数放到top_GUI的.m文件中，调用top_GUI.m文件，但是显示
Reference to non-existent field 'rv_idx'.

Error in ==> abc>start_simulation_Callback at 432
flagtime =
top_GUI(hObject, eventdata, handles);
Error in ==> gui_mainfcn at 96
        feval(varargin{:});
Error in ==> abc at 42
    gui_mainfcn(gui_State, varargin{:});
Error in ==> guidemfile>@(hObject,eventdata)abc('start_simulation_Callback',hObject,eventdata,guidata(hObject))