Retrieving data from slider

I've been using GUIDE and I'm having trouble getting the value from the slider.

In the generated function

function slider1_Callback(hObject, eventdata, handles)

I can get the value with

sliderValue = get(handles.slider1,'Value')

But if I try using that in a user defined function I get this error:

??? Undefined variable "handles" or
class "handles.slider1".

Did I miss something?

Answer 1

[Matt Fig]

In your user defined function doesn't accept the same three arguments, you will get this error. .

.

.

EDIT

Open the GUI with GUIDE. Double click on the slider to open the property editor. In the callback field, put this:

fun(gcbo,[],guidata(gcbo))

Where fun is the name of your function. fun will have to take three arguments just like shown:

function fun(hObject, eventdata, handles)

[t]

Do you mean like this?

function fun(hObject, eventdata, handles)

sliderValue = get(handles.slider1,'Value')

This gives me

??? Input argument "handles" is

undefined.

[Matt Fig]

How are you assigning this callback to the slider?

Answer 2

[t]

Like I posted in the comment above, I tried putting the same arguments in the function parameters

function fun(hObject, eventdata, handles) 
sliderValue = get(handles.slider1,'Value')

and I get

??? Input argument "handles" is 
undefined.

[Matt Fig]

But how are you telling the GUI to call your function fun? And where is fun, in the GUI M-file, or outside?

[t]

I've tried using fun() in the slider itself and on a button press just to test it.

fun() is in the GUI .m file, I'm doing everything in the same GUIDE generated .m file.

[Matt Fig]

See my above answer...

[t]

I guess that works but it's really not an appropriate solution. The data needs to be accessed by several functions, all called using the GUI at different times.

I will have to use global variable as I've been wasting a lot of time trying to work out how data is stored and retrieved, which I have to say is rather unintuitive and difficult to do (for such a simple process).

Thanks a lot for helping.