Accessing an actxserver COM object with a GUI

Hello,

I am trying to create a GUI that controls a third party program, which controls a camera.

I create the COM object as an activeX server as follows:

cameraHandle = actxserver('maxim.ccdcamera');

Now this object is in the workspace and I can interact with this object and make it do whatever I wish, no problem.

For example, the command for the camera to take a picture is:

invoke(cameraHandle,'Expose',exposureTime);

Now I would like to make one of the buttons in my GUI, do the same thing.

The code for the button is:

function buttonExpose_Callback(hObject, eventdata, handles)
% hObject     handle to buttonExpose
% handles     structure with handles and user data

% some commands here

How can I make this function act on the object cameraHandle?

Thanks!

Answer 1

[Geoff Hayes]

Dmitry - if you wish to use the same code in your GUI, then instantiate the cameraHandle in the _OpeningFcn of the GUI, save it to the handles structure, and then reference it in your pushbutton code. Try the following

 function myGui_OpeningFcn(hObject, eventdata, handles, varargin)

 % Choose default command line output for untitled3
 handles.output = hObject;

 % create the COM object
 handles.cameraHandle = actxserver('maxim.ccdcamera');

 % Update handles structure
 guidata(hObject, handles);

And then in your push button callback, just do

 function buttonExpose_Callback(hObject, eventdata, handles)

 exposureTime = 42;

 invoke(handles.cameraHandle,'Expose',exposureTime);

Note that any callback that receives the handles structure as an input parameter, can reference the cameraHandles via

 handles.cameraHandle

[Dmitry]

Geoff,

You're absolutely right. I was trying to figure out how to add the camera handle to the handles structure of the gui. This is the way to do that.

It works fine now. Thanks again!

Answer 2

[Abdur Rosyid]

This is interesting. I also need to do the same task, but in AppDesigner. Furthermore, I need to call the object in different callbacks. How can I do this in AppDesigner? Thank you.

[Geoff Hayes]

Abdur - this is not an answer to the question so please delete and post as a comment or create a new question. Please provide sufficient details.