Can't open Image. Help me. Please

function LoadImageGUI()
f = figure;
pb = uicontrol(f,'Style','pushbutton','String','Load Image','Position',[50 30 100 30], 'callback',@pb_Callback);
s = uicontrol(f,'Style','slider','Min',0,'Max',360,'Value',0,'SliderStep',[0.01 0.05],'Position',[180 30 300 30],'callback',@sliderCallback);
ax = axes('Parent',f,'Position',[.15 .25 .7 .7]);
hTxt = uicontrol('Style','text', 'Position',[260 65 20 20], 'String','0');
function pb_Callback(hObj, eventdata, handles)
    [filename, pathname] = uigetfile('*.tiff', 'Select a MATLAB code file');
   if isequal(filename,0)
   disp('User selected Cancel')
   else
   a=imread(filename, pathname);
   info = imfinfo([pathname filename]);
   num_images = numel(info);
   axes(handles.ax);
   imshow(a);
   handles.a=a;
   set(handles.Z, 'Min', 1);
   set(handles.Z, 'Max', num_images);
   set(handles.Z, 'Value', 1);
   set(handles.Z, 'SliderStep', [1/(num_images-1) , 1/(num_images-1) ]);
   handles.lastSliderVal = get(handles.Z,'Value'); % save the current/last slider value
   end
   guidata(hObject, handles); % Update handles structure
   end
  end

Answer 1

[Walter Roberson]

Change

   a=imread(filename, pathname);
   info = imfinfo([pathname filename]);

to

   filepath = fullfile(pathname, filename);
   a = imread(filepath);
   info = imfinfo(filepath);

[Hai Nguyen]

Thank you. But I can't open it.

Error using LoadImageHai/pb_Callback (line 16) Not enough input arguments. Error while evaluating UIControl Callback

[Walter Roberson]

Which is line 16?

Answer 2

[Jan]

You define the callback as:

pb = uicontrol([...], 'callback',@pb_Callback);

Then it is called as

function pb_Callback(hObject, EventData)

and the 3rd input "handles" is not defined.

Because you have defined the callback as nested function, this 3rd input is not needed. So simply omit it and use ax directly instead of the (undefined!) handles.ax.

handles.Z must fail also. Perhaps you want:

   set(s, 'Min', 1, 'Max', num_images, 'Value', 1, ...
       'SliderStep', [1/(num_images-1) , 1/(num_images-1) ]);

Summray: The advantages of using the handles struct and netsed functions are mixed completely. Decide for a clear strategy to share variables between callbacks. For further suggestions search for these terms in the forum: "share variables callbacks".