Populate one pop up menu on the basis of selection in another pop up menu.

Hello

I have two popup menus. popup menu1 : Directory and popup menu2: File names. In pop up menu 1 directory names should appear and in popup menu 2 Files in that directory should appear.

However, when I click any of the directory names in popup menu 1 then only the file names in first directory are being displayed. Please help me.

    for i = 1 : size(dirinfo,1)
    %Reading names of People
    People(i).Name = dirinfo(i,1).name;
      text{i}= People(i).Name;

    %Reading files of all people in structure format
     cd(Functions_Dir)

    People(i).Image_Name = ReadFileNames([Home_Dir '\Inputs\' dirinfo(i,1).name]); 
    text1{i}=  People(i).Image_Name ;

    cd ..
end
set(handles.popupmenu1,'string',text);
    a=get(handles.popupmenu1,'value');
  switch a
      case 1
     tex= text1{1};
      case 2
      tex= text1{2};
   end
     set(handles.popupmenu2,'string',tex);

Answer 1

[ES]

In call back of popupmenu1 you should write this..

a=get(handles.popupmenu1,'value');
switch a
    case 1
   tex= text1{1};
    case 2
    tex= text1{2};
 end
   set(handles.popupmenu2,'string',tex);

is this done? I am not able to see the functions in your code. That is why I am clarifying.

[Sidra Aleem]

yes this is done. This whole code is inside the call back function of popup menu 1. Popup menu 1 is also displayed correctly. The only problem is no matter what i select in popup menu 1 . popup menu 2 displays the contents of only first directory in pop up menu 1.

[Jan]

@Sidra: Then please post the relevant part of the code, such that we can help you to find the bug.

[Sidra Aleem]

function pushbutton7_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton7 (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,'fname')

       Present_Dir     = 'D:\我的文档\MATLAB\';                              %Present Working Directory
       Home_Dir        = [Present_Dir '\Image Processing'];                  % Home Directory
      Functions_Dir   = [ Home_Dir '\Functions' ];                            %Functions Directory

      Input_Dir=handles.fname;
      dirinfo = dir(Input_Dir);  
      dirinfo(~[dirinfo.isdir]) = [];                 %remove non-directories
  tf = ismember( {dirinfo.name}, {'.', '..'});        %remove current and parent directory.
  dirinfo(tf) = [];                                    %remove current and parent directory.
  for i = 1 : size(dirinfo,1)
      %Reading names of People
      People(i).Name = dirinfo(i,1).name;
        text{i}= People(i).Name;

      %Reading files of all people in structure format

   %%Popup for for image names 
      cd(Functions_Dir)

      People(i).Image_Name = ReadFileNames([Home_Dir '\Inputs\' dirinfo(i,1).name]); 
      text1{i}=  People(i).Image_Name ;

      cd ..

end
set(handles.popupmenu1,'string',text);
    a=get(handles.popupmenu1,'value');
  switch a
      case 1
     tex= text1{1};
      case 2
      tex= text1{2};
   end
set(handles.popupmenu2,'string',text1);  

clear ('dirinfo','i','tf');
end

[Jan]

@Sidra: Pleas read Format code in the forum . Thanks.

I cannot see where "popup menu 2 displays the contents of only first directory in pop up menu 1." and the code overlap. Perhaps it is the block:

a=get(handles.popupmenu1,'value');
switch a
    case 1
   tex= text1{1};
    case 2
    tex= text1{2};
 end
 set(handles.popupmenu2,'string',text1);

Here "tex" is created, but not used. Try to change it to:

index = get(handles.popupmenu1, 'value')
set(handles.popupmenu2, 'string', text1{index});

You can omit the trailing clear command. This is not useful in Matlab.

Using cd to change between directories is fragile: a user interaction of timer callback could change the current folder also. Prefer to use absolute file names, which contain the path. Then there is no need to change the current folder.

[Sidra Aleem]

tex is for displaying the file names present in selected directory from popup menu1.

   set(handles.popupmenu2,'string',tex);

I missed typed it to text1 in the above code. Using what you told has same effect. Its only displaying file names in first directory.

[Jan]

@Sidra: It is not easy to guess, what exactly "the first directory" is. Remember that I do not have the faintest idea about what you are doing.

I assume the problem appears at the location, where you define, what the "first" and "second" directory is. Where does this happen?

Do you know how to step through the code using the debugger?

[Sidra Aleem]

This part of the code takes directory names and displays them in first popup menu. I commented this part as well as is getting peoples names(directory names).

function pushbutton6_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton6 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

    % --- Executes on button press in Process_Batch.
    function pushbutton7_Callback(hObject, eventdata, handles)
    % hObject    handle to Process_Batch (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,'fname')

         Present_Dir     = 'D:\我的文档\MATLAB\';                              %Present Working Directory
         Home_Dir        = [Present_Dir '\Image Processing'];                  % Home Directory
        Functions_Dir   = [ Home_Dir '\Functions' ];                            %Functions Directory

        Input_Dir=handles.fname;
        dirinfo = dir(Input_Dir);  
        dirinfo(~[dirinfo.isdir]) = [];                 %remove non-directories
    tf = ismember( {dirinfo.name}, {'.', '..'});        %remove current and parent directory.
    dirinfo(tf) = [];                                    %remove current and parent directory.
    for i = 1 : size(dirinfo,1)
        %Reading names of Directory
        People(i).Name = dirinfo(i,1).name;
        text{i}= People(i).Name;
  end
  set(handles.popupmenu1,'string',text)
  end