ROI deleted event listener
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Is there a listener event for when an ROI has been deleted from an axes? For example, like so:
addlistener(h,'ROIDeleted',@allevents);
But this doesn't seem to work.
If not, how could I check when a ROI shape has been deleted by the user through GUIDE?
Many thanks.
6 Comments
Adam Danz
on 10 Jan 2023
Edited: Adam Danz
on 10 Jan 2023
I know what you mean @Brian Derstine about the collapsed sections. Whenever I text search a doc page, I expand all components first to make sure I don't miss something. This option is at the top, right of doc pages that contain expansion fields.
About the callbacks, note that these are not callback function. They are events.
Answers (2)
Matthew Siefring
on 10 Jan 2022
As an alternative to Adam's answer, you can use 'DeletingROI' as the event name parameter for the addListener function.
addlistener(h,'DeletingROI',@allEvents);
This way, the allEvents function will only be triggered when the user deletes the ROI interactively, instead of whenever a cleanup is triggered on the ROI object.
Adam Danz
on 2 Nov 2020
Edited: Adam Danz
on 2 Nov 2020
Use onCleanup to define a function that is evoked when the ROI is deleted. Store the onCleanup handle within the object.
Demo: Displays "ROI deleted" when the ROI object is deleted.
I = imread('baby.jpg');
figure
imshow(I)
h = images.roi.Circle(gca,'Center',[1000 1000],'Radius',500);
h.UserData.OnCleanup = onCleanup(@()allevents);
% Show figure, pause
drawnow;
pause(1)
% delete ROI obj
delete(h)
function allevents
fprintf('ROI deleted\n')
end
3 Comments
Brian Derstine
on 9 Jan 2023
Edited: Brian Derstine
on 9 Jan 2023
Is there an undocumented "ROIDeleted" function that gets called after "DeletingROI"? I am able to run code during the DeletingROI event but no matter what I do, the polyline always gets deleted after that function finishes. I want to prevent the polyline from being deleted all at once but allow individual vertices to be deleted. One way I tried to do this was by setting the "Deletable" property to 0/false, but after doing that I can no longer delete vertices on the polyline. I can add and move vertices no problem. Do I need to override the default context menu options and manually remove the Delete Polyline option somehow?
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