How to save an app property to an .m file?

I'm working on an app in App Designer and have created a public property that is assigned a folder path as a char. The path can be edited/changed via an edit field and needs to be saved to a file for future reference, however, when I try to save I recieve an error saying the property is not a scalar structure. I test the property to confirm it is a structure and is scalar, which give results of 1. So, I'm confused what is wrong.

app.dataPaths.projectFolder = app.ProjectFolderEditField.Value;
app.ProjectFolderLabel.Text = '';

st = isstruct(app.dataPaths);
sc = isscalar(app.dataPaths);

% Save the new dataPath variable
save('StartUpPathData.mat','-struct','app.dataPaths');

Any help or suggestions are appreciated.

Answer 1

[Walter Roberson]

When you save() with -struct then the name that you give must be the name of a full variable.

That is, copy app.dataPaths to a variable and save the variable.

[Josh Drake]

That worked, thanks!