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Passing objects from app designer to the workspace

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Hello , I'm using app designer and I am creating object when some button clicked, (in the callback function) i'm trying to use the object that created in the callback funcion in the workspace. I know that i can create some "global" object in the properties and then use app.obj. There is other way that i can pass the object from the callbackfunction to the workspace? or the only way is to use the properties.
Thank you very much :)

Accepted Answer

Allen on 19 Oct 2022
Though I would recommend using one of @Adam Danz's solutions since they are typically a safer method of passing data, assignin can be used to programmatically assign a variable to the workspace.
See the following help page for details on how to use the assignin function.
Ron on 26 Oct 2022
I am using appDesigner,
Function RunButtonPushed(app,event) //NOTE : this is on gray cant add a return value
obj=importdata(somepath) //NOTE : The path is matlab data that have run method // NOTE : after the run , nothing happens because the variable
end obj is uknown in the workspace i guess beacuse in the
end of this function there is END
Allen on 17 May 2023
When working with callback functions in AppDesigner use the app object that is called in as the first input argument to store additional user defined values. To do that you will need to setup a new property in a user defined properties block. Typically, I will create at least a basic propery arbitrarily named Data similar to the following. This will store the imported data within the application and can be accessed at any time. If you are familiar with using GUIDE, you will find that this works similarly to behavior of the guidata function, but is a more simplified process.
classdef UserAppClass < matlab.apps.AppBase
properties (Dependent, SetAccess = public)
% Additional method blocks containing user defined functions and app callback functions
With a dedicated property setup you can then store and retain the imported data similarly.
% Callback function assigned to the import data pushbutton
function RunButtonPushed(app, event)
app.Data = importdata(somepath);
% Callback function assigned to an demonstrational plot data button
function PlotDataButtonPushed(app, event)
% Callback function stops immediately if the Data property is empty
if isempty(app.Data)
% Assumes data was a numeric double-array with at least two columns

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More Answers (1)

Adam Danz
Adam Danz on 18 Oct 2022
The best way to access the object created by an app is to store the handle to the object as a public property of the app and to access that handle through the app object, stored as a variable in your workspace.
More info


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