How to wait for a button to be pressed?

Hi,

I have the following code:

% --- Executes on button press in insertAntenna.
function insertAntenna_Callback(hObject, eventdata, handles)
% hObject    handle to insertAntenna (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
% Coloca a antena nas coordenadas seleccionadas pelo ginput %
handles  = guidata(hObject)
[x_gNB, y_gNB] = ginput(1);

handles.nAntena = handles.nAntena + 1
Antena_x = x_gNB;
Antena_y = y_gNB;

rectangle('Position', [(Antena_x - handles.Rwidth/2) (Antena_y - handles.Rheight/2)...
    handles.Rwidth handles.Rheight], 'FaceColor', 'r','LineStyle', 'none');

uiwait(waitfor(sectorAngle_Button_Callback(hObject, eventdata, handles)));    % Wait for the respective sector

handles.Antena(handles.nAntena).Antena_x = Antena_x;
handles.Antena(handles.nAntena).Antena_y = Antena_y;

handles.Antena(handles.nAntena).Info = handles.Antena(1).Info;
handles.Antena(handles.nAntena).Altura = handles.Antena_Altura;
handles.Antena(handles.nAntena).Direction = handles.AntenaDirection;

guidata(hObject, handles)

% --------------------------------------------------------------------------------------------------------------------------
% --- Executes on selection change in sectorAngle.
function sectorAngle_Callback(hObject, eventdata, handles)
% hObject    handle to sectorAngle (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hints: contents = cellstr(get(hObject,'String')) returns sectorAngle contents as cell array
%        contents{get(hObject,'Value')} returns selected item from sectorAngle
contents = cellstr(get(hObject,'String'))   % Options of popupmenu 
selected = contents{get(hObject,'Value')}   % Value selected by the user through popupmenu 

if strcmp(selected,'Sector1')
    handles.AntenaDirection = 300;
elseif strcmp(selected,'Sector2')
    handles.AntenaDirection = 180;
else 
    handles.AntenaDirection = 60;
end

guidata(hObject, handles)

% --------------------------------------------------------------------------------------------------------------------------
% --- Executes during object creation, after setting all properties.
function sectorAngle_CreateFcn(hObject, eventdata, handles)
% hObject    handle to sectorAngle (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    empty - handles not created until after all CreateFcns called

% Hint: popupmenu controls usually have a white background on Windows.
%       See ISPC and COMPUTER.
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor','white');
end

s1 = 'Sector1';
s2 = 'Sector2';
s3 = 'Sector3';
sectors = char(s1, s2, s3);
set(hObject,'string',sectors)

% --------------------------------------------------------------------------------------------------------------------------
% --- Executes on button press in sectorAngle_Button.
function sectorAngle_Button_Callback(hObject, eventdata, handles)
% hObject    handle to sectorAngle_Button (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

In the line

uiwait(waitfor(sectorAngle_Button_Callback(hObject, eventdata, handles)));    % Wait for the respective sector

I want to wait for the button sectorAngle be pressed in order to handles.AntenaDirection value.

What I am doing wrong?

Thanks!

Answer 1

[Image Analyst]

Don't put that code

s1 = 'Sector1';
s2 = 'Sector2';
s3 = 'Sector3';
sectors = char(s1, s2, s3);
set(hObject,'string',sectors)

into the CreateFcn. I never put anything it there. Just leave the createfcn function alone. Put it into the sectorAngle_Button_Callback callback or your OpeningFcn function.

And don't have the uiwait(waitfor()) line of code - it's not necessary since the button is already waiting for you to click it. If you still have trouble, attach both the .fig file and .m file.

Answer 2

[Adam Danz]

Place this in the line where you want execution to pause

uiwait(handles.figure1)  % use your figure handle

Then, from within the button's callback function, add the line,

uiresume(handles.figure1)  % use your figure handle

[Oliver Lestrange]

Hi Adam,

Thanks a lot!

When it exits this part of code the handles.AntenaDirection stays again with the initialized value. Can you understand why this is happening, with the posted code?

% --- Executes on selection change in sectorAngle.
function sectorAngle_Callback(hObject, eventdata, handles)
% hObject    handle to sectorAngle (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hints: contents = cellstr(get(hObject,'String')) returns sectorAngle contents as cell array
%        contents{get(hObject,'Value')} returns selected item from sectorAngle

contents = cellstr(get(hObject,'String'))   % Options of popupmenu 
selected = contents{get(hObject,'Value')}   % Value selected by the user through popupmenu 

if strcmp(selected,'Sector1')
    handles.AntenaDirection = 300;
elseif strcmp(selected,'Sector2')
    handles.AntenaDirection = 180;
else 
    handles.AntenaDirection = 60;
end

guidata(hObject, handles)

Thanks again

[Adam Danz]

What is handles.AntenaDirection? It looks like you're overwriting the handle variable with a numeric value instead of assigning the numeric value to the AntenaDirection object.

Instead,

handles.AntenaDirection.Value = 300;

but since I don't know what handles.AntenaDirection is, the Value property may not be the correct property.

Or, perhaps handles.AntenaDirection stores a value. In that case, I don't see where you're assigning that value to a GUI object.

[Oliver Lestrange]

I want to handles.AntenaDirection stores the value 300, 180 or 60, and then when I access it in

handles.Antena(handles.nAntena).Direction = handles.AntenaDirection;

on the insertAntenna_Callback function I have that value, and not the value with a initialize in the gui opening function.

Important notice that the sectorAngle_Callback function is before insertAntenna_Callback.

[Adam Danz]

That's clearer.

What is the value of selected just before the conditional statements?

It may be the case that none of your conditions are met and if the initial value is 60, that value wouldn't change.

By the way, a switch/case block is sometimes a better way to organize discrete options than if/else statements.

if swtich(lower(selected))
case 'sector1' % lowercase
    handles.AntenaDirection = 300;
case 'sector2' % lowercase
    handles.AntenaDirection = 180;
otherwise
    handles.AntenaDirection = 60;
end

[Oliver Lestrange]

"What is the value of selected just before the conditional statements" - Is Sector1, Sector2 or Sector3, depending of which I selected in the pop-up menu, just like is supposed to.

Thanks for the switch/case suggestion.