Programmatically setting a radio button from within App Designer

23 views (last 30 days)
I am trying to change the selected radio button with in a button group from within the app program.
I have an app for which I take the state of the app, put it into a dictionary and save that. Now I want to retrieve the dictionary, and then apply the recovered state definition to the app. This includes selecting the correct radio buttons.
I have the text associated with the selected button, but I can't figure out how to use that to change the selected button to the desired one. If I use a statement like the following: 'app.TelescopeTypeButtonGroup.SelectedObject.Text = Cassegrain ;' then is changes the text assocated with the selected button, but does not change the button that is selected.
I tried to do a series of commands that set the selected button value to "0", hoping that would cycle through all the buttons, but it didn't always cycle through all of the buttons. I have run out of work arounds. Any thoughts?
Thanks
Peter

Answers (3)

Voss
Voss on 25 Feb 2025
You need to refer to the radio button object itself, e.g., using its name in the app structure:
app.TelescopeTypeButtonGroup.SelectedObject = app.Button5;
where app.Button5 refers to the appropriate radio button object in the button group.
Another, less direct, way is, given the Text of some radio button, get the appropriate radio button object from that and then set that to be the SelectedObject, e.g.:
button_txt = 'Cassegrain';
buttons = app.TelescopeTypeButtonGroup.Children;
labels = get(buttons,{'Text'});
idx = strcmp(labels,button_txt);
app.TelescopeTypeButtonGroup.SelectedObject = buttons(idx);
The attached app shows both ways in its startupFcn.

Peter Cheimets
Peter Cheimets on 25 Feb 2025
This is what I ended up doing. I couldn't get the "get" statement to work. So I walked through the lables one by one in the while loop.
Note: state_dic is the dictionary with the app state, and state_dic_keys are the keys from the dictionary extracted so that I could walk through the dictionary in order and it has all of the names in place.
Peter
button_txt = char(state_dic{state_dic_keys(i)});
which_buttons = extractBefore(char(state_dic_keys(i)),'SelectedObject.Text');
buttons = [which_buttons,'Children'];
labels = eval([buttons]);
idx = 1; %initialize the value
while strcmp(labels(idx).Text,button_txt) == 0
idx = idx + 1; %inc idx if this isn't the right button
end
eval([buttons,'(',num2str(idx),').Value = 1;'])
  2 Comments
Voss
Voss on 25 Feb 2025
which_buttons = extractBefore(char(state_dic_keys(i)),'SelectedObject.Text');
I assume which_buttons produced there is a character vector that's something like 'app.TelescopeTypeButtonGroup.', i.e., the name of the radio button group with a period on the end.
If that's true, then the code can be:
button_txt = char(state_dic{state_dic_keys(i)});
buttongroup = eval(extractBefore(char(state_dic_keys(i)),'.SelectedObject.Text'));
buttons = buttongroup.Children;
labels = get(buttons,{'Text'});
idx = strcmp(labels,button_txt);
buttongroup.SelectedObject = buttons(idx);

Sign in to comment.


Image Analyst
Image Analyst on 26 Feb 2025
I wouldn't use eval. What if you just set the other buttons also if setting the one you want doesn't change the others automatically, like
% Set radio button you want
app.radioButton1.Value = "on";
% Deselect others
app.radioButton2.Value = "off";
app.radioButton3.Value = "off";

Categories

Find more on Migrate GUIDE Apps in Help Center and File Exchange

Products


Release

R2024b

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!