SelectionType of Mousebutton is empty

Hello!

For context: i'm a beginner and want to design an app in Matlabs App Designer where the user needs to click on a small image in the apps window (which is otherwise empty). There needs to be two different actions weather the right or left mousebutton is pushed. With the right mousebutton there should'nt be any difference weather the mouse is positioned above the image or not.

I found several solutions that use 'get' to get the 'SelectionType' in the function WindowButtonDownFcn. However in my case whatever i push wherever i am, the resulting variable 'clickType' is instead of 'alt' or 'normal' just an empty 0x0 double value. What am i doing wrong? Is there a way i can just add a different callback function for the right mouseclick? Or is there maybe a more elegant way to approach this?

Thanks in advance!

function WindowButtonDownFcn(app, event)
    figHandle = ancestor(app, 'figure');
    clickType = get(figHandle, 'SelectionType');
    
    if strcmp(clickType, 'alt')
        % Do something for right Mouseclick
    else
        % Do something else
    end
end

Answer 1

[Steven Lord]

Likely your figHandle variable is empty. If you're looking to determine how the mouse button was pressed in your app window why not ask your app window (whose handle is app) what its SelectionType property value is?

[Barbara Kammerl]

If i change 'figHandle' in line 3 to 'app' and erase line 2, then i get an error stating that Matlab couldn't find the method 'get'.

[Steven Lord]

Sorry, I typed that first message on my phone and so didn't type as much as I perhaps should have. I'm not sure the get approach for retrieving properties is defined for uifigure objects. Try:

 clickType = app.SelectionType;

If that doesn't work, can you show us the output of this command? Add it as the first line in that function and reproduce the error.

whos app

[Barbara Kammerl]

It immediatly produces the error message "Unrecognized method, property or field 'SelectionType' for class 'Name_of_app'.

the output of

whos app

gets me this: (sorry if thats not what you ment by it)

[Barbara Kammerl]

After a bit of trying i found a solution that works.

clickType = get(event.Source).SelectionType;

gives back the correct value of 'alt' when using the right mouse button. Sadly this only works outside of the image. The image itself can apparently only be clicked on with the left mouse button (won't go into the callback function when right-clicked). Should i open up a new question for this, or is there maybe an easy and quick fix? Thank you for your time!