How can i make this drop down menu in GUI change the line style of my graph

Hello all, i'm currently working on a project that creates a GUI that plots functions of any type. One thing i would like it to do is be able to vary the line style (solid,dashed, etc.). Having not been taught GUI i have trouble coding. I currently have this in my popupmenu callback

if true
  % code
dstr = get(hObject, 'String');
val = get(hObject,'Value');
% Set current data to the selected data set.
switch str{val};
case 'Solid line' 
 handles.current_data = handles.solid;
case 'Dashed line' 
 handles.current_data = handles.dashed;
 case 'Dotted line' 
 handles.current_data = handles.dotted;
case 'Dash-dot line' 
 handles.current_data = handles.dashdot;
end

guidata(hObject,handles)

end

I then go to my push button to create the graph and i add line=get(handles.popupmenu1,'String'); thinking that when i go to plot i could place plot(....'linestlye', line) to get the desired linestyle.

Also i defined the handles in the pop up menu in the opening function as the following

if true
  % code  
solid='-'
dashed='--'
dotted=':'
dashdot='-.'
handles.solid=solid
handles.dashed=dashed
handles.dotted=dotted
handles.dashdot=dashdot

end Any help would be greatly appreciated!

Answer 1

[Walter Roberson]

Be sure to guidata() after you initialize handles.solid and so on.

To put the change into effect you need to have the handles of the lines to be affected. You might have recorded those, or you might know the axes they are in.

set(findobj(handles.TheAppropriateAxes, '-type', 'line'), 'LineStyle', handles.current_data);

[Stephen Hawkins]

So i should put guidata() after handles.solid like where i initially define it?