Two Buttons with same Variable in App Designer

Hi Guys,

I'm new to the App Designer and I have a (simple?) question:

I have two buttons. The first one opens a tcp/ip connection to a device. The callback function got the following code (just ignore the lamps):

% Button button pushed function
      function VerbindenButton(app)
          t = tcpip('192.168.2.3', 29536, 'NetworkRole', 'Client')
          fopen(t);
          app.Lamp.Enable = 'on';
          app.Lamp2.Enable = 'off';
      end

        % Button2 button pushed function
        function CAN0Button(app)

            fwrite(t,'< open can0 >');
        end

When I click the second button (after the first one) I get the error 'Undefined function or variable 't'.' So here is my question: How do I get the value/information of t into the second button function?

Answer 1

[Melissa Williams]

Hi Fabian, You can add an app property to pass data from one callback to another. To do this:

1. In Code View, press the "+Property" button in the Insert section of the Editor Tab of the toolstrip.
2. In the editor, rename "Property" to "t" (or another name you like)
3. In your VerbindenButton and CAN0Button callbacks, change "t" to "app.t"

To learn more you can refer to this documentation: http://www.mathworks.com/help/matlab/creating_guis/share-data-across-callbacks-in-app-designer.html