access data in App-Designer in nested function call

I have defined a variable cr as a public propertie and can refer to it within the program by usind app.cr. However I call a function withinh function

where I need to use the variable, but by running the programm I get an error message:

Unrecognized field name "cr".

Error in SolarsystemOrbits_03/EarthOrbit (line 413)

app.TMG_solver( n, x, y, z, vx, vy, vz, bx, by, bz);

Error in SolarsystemOrbits_03/OrbitMain (line 191)

app.EarthOrbit;

Error in SolarsystemOrbits_03/ComputeButtonPushed (line 1341)

app.OrbitMain;

What am I doing wrong.

Answer 1

[Aditya]

Hi Claus,

It looks like you're encountering an issue with accessing the cr property within a nested function call in MATLAB App Designer. In MATLAB, nested functions do not automatically have access to the properties of the app unless explicitly passed.

Based on the error that you have provided, your file structure should look like this for it to work properly:

properties (Access = public)
    cr
end
    
methods (Access = private)

    function ComputeButtonPushed(app, event)
        app.OrbitMain();
    end

    function OrbitMain(app)
        app.EarthOrbit();
    end

    function EarthOrbit(app)
        % Access the cr property
        disp(app.cr);
        
        % Call another function without passing app explicitly
        app.TMG_solver(n, x, y, z, vx, vy, vz, bx, by, bz);
    end

    function TMG_solver(app, n, x, y, z, vx, vy, vz, bx, by, bz)
        % Access the cr property
        disp(app.cr);
        
    end

end

Additional Suggestions

1) Clarify the Scope of cr: Ensure that 'cr; is defined as a public property so it can be accessed throughout the app.

2) Debugging Steps:

• Print Statements: Add print statements to verify that the functions are being called as expected.
• Breakpoint: Set breakpoints in the MATLAB editor to inspect the state of the app object and its properties.

If you are having the same file structure and still facing the issue, could you please provide more details to reproduce the issue? You can share the functions that are being used within the file which are leading to this error.

I hope this helps!

[Claus Schmidt]

Hello Aditya, Thank you for your very quick answer. I will try you hints and keep you informed.

Claus