MATLAB: Accessing a variable used in a botton from another button

gui

Hi , I am using matlab R2013a

I declared a variable name as wav in a button's callback function as shown below

function record_Callback(hObject, eventdata, handles)

wav=wavrecord(10*8000,8000);

Now, I want to access this variable from the callback function of another button as shown below

function play_Callback(hObject, eventdata, handles) sound(wav);

Any easy way to do it?

Best Answer

This topic is dicussed frequently and you can find it e.g. by searching in this forum for "share variable between callbacks". See e.g. http://www.mathworks.com/matlabcentral/answers/146260-how-to-share-variables-between-two-gui-callbacks

function record_Callback(hObject, eventdata, handles)
handles = guidata(hObject);
handles.wav = wavrecord(10*8000,8000);
guidata(hObject, handles);
function play_Callback(hObject, eventdata, handles)
handles = guidata(hObject);
sound(handles.wav);

Related Solutions

MATLAB: Stopping a function in between GUI

Max - rather than using the sound function to play the audio recording, consider using an audio player object which provides the ability to stop the audio playback. For example, in your play button callback, you could do

% --- Executes on button press in pushbutton1.
function pushbutton1_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB

% handles    structure with handles and user data (see GUIDATA)

fs = 44100; % Hz

t = 0:1/fs:10; % seconds
f = 440; % Hz
y = cos(2.*pi.*f.*t);
handles.hAudioPlayer = audioplayer(y,fs);
guidata(hObject, handles);
play(handles.hAudioPlayer);

The last three lines in the above code, we create the player, save the updated handles structure (which has a field for the handle to the audio player), and then start the (non-blocking) playback.

Now, in the stop button callback, you could do

% --- Executes on button press in pushbutton3.
function pushbutton3_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton3 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
if isfield(handles,'hAudioPlayer')
    stop(handles.hAudioPlayer);
end

We check to see if there exists an audio player handle field in the handles object, and if so, then we just stop the playback.

Try the above and see what happens!

MATLAB: H i every one , i need to declare a counter such that if any one of the four buttons is pressed a specefic funtion specified in the fifth button is performed.Suppose UserData can not be used it reserved for something else

Use guidata, which calls setappdata and getappdata internally:

function pushbutton1_Callback(hObject, eventdata, handles)
handles = guidata(hObject);
handles.counter = 1;
guidata(hObject, handles);
% And the same for the other callbacks...
function pushbutton5_Callback(hObject, eventdata, handles)
handles = guidata(hObject);
switch handles.counter
  case 1
  case 2
  case 3
  case 4
  otherwise  % No SWITCH without OTHERWISE
    error('Programming error')
  end
end

Best Answer

Related Solutions

MATLAB: Stopping a function in between GUI

MATLAB: H i every one , i need to declare a counter such that if any one of the four buttons is pressed a specefic funtion specified in the fifth button is performed.Suppose UserData can not be used it reserved for something else

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