switch case in GUI pop-up menu

I've a pop-up menu with 5,10,15,20 the contents in that menu. using switch I've created this, what changes i need to do with this statement?

    val=get(hObject,'value');
    switch val
        case '5'
            n=5;
        case '10'
            n=10;
        case '15'
            n=15;
        case '20'
            n=20;
    end
    handles.n = val;
    guidata(hObject, handles);

where it represents number of output images. I'm suppose to get 5 images at output if user selects 5 in pop-up menu, 10 images if 10 is selected and so on.... But I'm getting only 1 image if i select 5, 2 images if 10, 3 if 15... like that, what's wrong in my switch statement? any appropriate answer is appreciable.

[Vishal Rane]

Can't say anything based on the code you have given. Can you share the code where "n" is actually used ?

[Chethan]

well sorry for that, above code is written in popup menu callback function.. where i actually use this 'n' is

    function Search_Callback(hObject, eventdata, handles)
    % hObject    handle to Search (see GCBO)
    % eventdata  reserved - to be defined in a future version of MATLAB
    % handles    structure with handles and user data (see GUIDATA)
    n = handles.n;
    isTexture = get(handles.Texturecheck,'Value');
    isColour = get(handles.colourcheck,'Value');
    if and(isTexture, isColour)
            % Colour search...
            % Open database txt file... for reading...
            fid = fopen('database.txt');
            resultValues = [];      % Results matrix...
            resultNames = {};
            i = 1;                  % Indices...
            j = 1;
            while 1
                imagename = fgetl(fid);
                if ~ischar(imagename), break, end      

                [X, RGBmap] = imread(imagename);
                HSVmap = rgb2hsv(RGBmap);
                D = quadratic(handles.queryx, handles.querymap, X,HSVmap);
                resultValues(i) = D;
                resultNames(j) = {imagename};
                i = i + 1;
                j = j + 1;
            end
            fclose(fid);
            % Sorting colour results...
            [sortedValues, index] = sort(resultValues);   
            fid = fopen('colourResults.txt', 'w+');        
            *for i = 1:n                 % Store top n matches...*
            tempstr = char(resultNames(index(i)));
            fprintf(fid, '%s\r', tempstr);
            disp(resultNames(index(i)));
            disp(sortedValues(i));
            disp('  ')
        end

I'm suppose to get 5 images at output if user selects 5 in pop-up menu, 10 images if 10 is selected and so on.... But I'm getting only 1 image if i select 5, 2 images if 10, 3 if 15... like that

Answer 1

[Jing]

It looks like you're using the selected index(the value you get is index...) of the popup menu, not the selected content for getting the output. When you use switch, it should be like this:

      switch val
          case 1
              n=5;
          case 2
              n=10;
          case 3
              n=15;
          case 4
              n=20;
      end
      handles.n = n; %supposed handles.n is what you use to get output images.

[Chethan]

Well, I'm getting error like Reference to non-existent field 'n'.

To over come this i added handles.n=val;

in opening function, even though I'm not getting exact result.