MATLAB: Error :Input argument “handles” is undefined with the axes

errorguihandlesMATLAB

Hello,
I tried to implement a simple GUI in MAtlab7.7 like the below
function varargout = start1(varargin)   
gui_Singleton = 1;
gui_State = struct('gui_Name',       mfilename, ...
                   'gui_Singleton',  gui_Singleton, ...
                   'gui_OpeningFcn', @start1_OpeningFcn, ...
                   'gui_OutputFcn',  @start1_OutputFcn, ...
                   'gui_LayoutFcn',  [] , ...
                   'gui_Callback',   []);
if nargin && ischar(varargin{1})
    gui_State.gui_Callback = str2func(varargin{1});
end
if nargout
    [varargout{1:nargout}] = gui_mainfcn(gui_State, varargin{:});
else
    gui_mainfcn(gui_State, varargin{:});
end
% End initialization code - DO NOT EDIT
function start1_OpeningFcn(hObject, eventdata, handles, varargin)
handles.output = hObject;
% Update handles structure
guidata(hObject, handles);
function varargout = start1_OutputFcn(hObject, eventdata, handles) 
varargout{1} = handles.output;
start=uicontrol('Style','pushbutton','String', 'start', 'Position',[20 400 50 20],'Callback',@startbutton_Callback);
Exit=uicontrol('Style','pushbutton','String', 'Exit', 'Position',[20 20 50 20],'Callback',@pushbutton1_Callback);
function pushbutton1_Callback(hObject, eventdata, handles)
display('Goodbye');
close(gcf);
function startbutton_Callback(hObject, eventdata, handles)
axes(handles.axes2);
plot(sin(0:0.1:10))
It is giving error as
??? Input argument "handles" is undefined.
Error in ==> start1>startbutton_Callback at 91
axes(handles.axes2);
??? Error while evaluating uicontrol Callback

Best Answer

Only the object and the event are automatically added as input arguments to a callback. If you want handles to be passed as well you need to arrange that. When you use GUIDE to create graphic objects, it automatically puts appropriate code as the callback.
In your situation, where you are using only a single figure, I would recommend removing handles from the argument list, leaving the uicontrol() the way it is, and adding the following as the first line of code in the callback:
handles = guidata(hObject);
Related Question