share/load data (mat-file) AppDesigner

Hy everybody, I would share soma variable from mat-file (workspace_invaso.mat) in AppDesigner, but I can't do it. I don't want to load the mat-file in every callback function. Best regard, Dario

    % code
  classdef Volume_invaso_1 < matlab.apps.AppBase

    % Properties that correspond to app components
    properties (Access = public)
        UIFigure                 matlab.ui.Figure
        UITable                  matlab.ui.control.Table
        VOLUMEUTILEDINVASOLabel  matlab.ui.control.Label
        CapacitTextAreaLabel     matlab.ui.control.Label
        CapacityTextArea         matlab.ui.control.TextArea
        Button_Filo_Teso         matlab.ui.control.Button
        Button_Rippl             matlab.ui.control.Button
        Button_Peaks             matlab.ui.control.Button
    end

    properties (Access = private)
        load workspace_invaso.mat % Share variables
    end

    methods (Access = private)

        % Code that executes after component creation
        function startupFcn(app)
            load workspace_invaso.mat;
            app.UITable.Data=[Q_serie.annuale,Ve,Qu,Vu,Vc];
            app.UITable.RowName={'Gennaio';'Febbraio';'Marzo';'Aprile';'Maggio';...
    'Giugno';'Luglio';'Agosto';'Settembre';'Ottobre';'Novembre';'Dicembre'};

        end

[dario cecchetti]

Very clear! Great! Thanks!

Answer 1

[Ameer Hamza]

The startupFcn just execute once, at the start of the app, so you are loading the file just once, not at every callback.

[dario cecchetti]

Yes I agree with you, but I would like to load mat file just once. I tried to do it in PROPERTY (acces==private), but Matlab get me an error.

[Ameer Hamza]

I already said that startupFcn will only execute once. It appears that you are confused about how to share data after loading in startupFcn. You are getting the error because following is not a valid syntax

properties (Access = private)
   load workspace_invaso.mat % Share variables
end

you can only declare the name of properties here.

Here is one way how you can share data between functions after loading. Create a private property data (or any other name) like this

properties (Access = private)
  data
end

In the startupFcn, call the load() like this

app.data = load('workspace_invaso.mat');

this will return a struct with same fields as your mat file. For example, if your mat file has a variable named X, you can access it like app.data.X and this property is visible to all the function in the app so you can use app.data.(variable name) anywhere and access the required value.

[dario cecchetti]

Great! Thanks for all!!!

[Ameer Hamza]

You are welcome.