Accessing appdesigner objects properties from a function

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I am trying to create a basic calculator with every operator button calling the same function .I am able to do this with the button label as parameter and a switch case inside the called function to check the prameter and proceed accordingly. How can I improve the app in following terms:
  1. Not pass the label of operator button everytime. Can the button which was pushed be identified without passing the button label? Identifying the operator which is the button label is the goal here.
  2. Have a common buttonPushed callback for multiple buttons since they all call the same function.
  3. Possibly improve how i append the history cell.
properties (Access = private)
history = {'History'}; % Description
end
methods (Access = private)
function func(app,operator)
switch operator
case '+'
app.ResultEditField.Value = app.Number1EditField.Value+app.Number2EditField.Value;
case '-'
app.ResultEditField.Value = app.Number1EditField.Value-app.Number2EditField.Value;
case '*'
app.ResultEditField.Value = app.Number1EditField.Value*app.Number2EditField.Value;
case '/'
app.ResultEditField.Value = app.Number1EditField.Value/app.Number2EditField.Value;
end
a=sprintf('\n %d %c %d = %d',app.Number1EditField.Value,operator,app.Number2EditField.Value,app.ResultEditField.Value );
app.history(end+1)={char(a)};
end
end
% Callbacks that handle component events
methods (Access = private)
% Button pushed function: addButton
function addButtonPushed(app, event)
app.func(app.addButton.Text);
end

Answers (1)

Jon
Jon on 20 Jan 2022
First, I'm not sure why you would want to just have a single button pushed callback for multiple buttons.
Why not just break that function up and have the appropriate line of code in the button pushed callback for each of the individual buttons. So for example have the button pushed callback for the plus button have just the line:
app.ResultEditField.Value = app.Number1EditField.Value+app.Number2EditField.Value;
Assuming you really want to have a common button pushed callback with the switch case as you show, you could have each individual button have a button pressed callback that called the common function with the operator argument set appropriately.
So for example the button pushed call back for plus would have the line of code:
func('+')
  5 Comments
Biraj Khanal
Biraj Khanal on 21 Jan 2022
No, the initial approach does not solve what I am trying to learn. And what you wrote about calling the same function is exactly what I did above. But in this case, there is no other function of the buttons other than all calling the same function. This is the reason why I am trying to find a way to combine it.
Further, your suggestion to use the + operator generates a string instead of a character array that I could add later to the history cell which I use with a button to display as a text for a label field. What do you think would be the best way to save lines of character array or strings (i cannot figure out which one is better here) and then display them later? I hope you get the idea of me trying to display the calculator history with a history button here.
Jon
Jon on 21 Jan 2022
I'm sorry. I'm not really understanding then what it is that you are trying to do but are unable to do.

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