Getappdata and setappdata

Hi, I have a problem with getappdata and setappdata. I was wrote the matlab help but I don't understand everything. Do you have any example code with this metods?

Answer 1

[Chandra Kurniawan]

Hello,

I will give you sample code for this topic.

I have a .fig file (figure) that consists of 2 axes (axes1 and axes2) and 2 pushbutton (pushbutton1 and pushbutton2).

Then, here the m-file code

function varargout = untitled(varargin)
gui_Singleton = 1;
gui_State = struct('gui_Name',       mfilename, ...
                   'gui_Singleton',  gui_Singleton, ...
                   'gui_OpeningFcn', @untitled_OpeningFcn, ...
                   'gui_OutputFcn',  @untitled_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

function untitled_OpeningFcn(hObject, eventdata, handles, varargin)
    handles.output = hObject;
    guidata(hObject, handles);

function varargout = untitled_OutputFcn(hObject, eventdata, handles) 
    varargout{1} = handles.output;

function pushbutton1_Callback(hObject, eventdata, handles)
    I = imread('cameraman.tif');
    imagesc(I, 'parent', handles.axes1);
    setappdata(handles.pushbutton1,'img',I);

function pushbutton2_Callback(hObject, eventdata, handles)
    J = getappdata(handles.pushbutton1,'img');
    bw = im2bw(J);
    imagesc(bw, 'parent', handles.axes2);

Watch at pushbutton1_callback. Fisrt I read image with command imread and display it to the axes1.

Then after finished, I store the variable I to the handle : 'pushbutton1' as name : 'img' with command :

setappdata(handles.pushbutton1,'img',I);

Then watch at pushbutton2_callback

I used command

J = getappdata(handles.pushbutton1,'img');

to get the the last value which I stored at handle 'pushbutton1' which name = 'img'.

And then I successfully create a binary image with input parameter 'J'

Answer 2

[Paulo Silva]

Passing data between GUIDE callbacks without globals in MATLAB from Doug's MATLAB Video Tutorials

Ways to Manage Data in a GUIDE GUI

Matlab GUI: Handling User Data and Images>