Using drawline() i have attached a callback function that allows a user to draw lines on the axes. Initially, clicking the button pops up a new window to carry out the drawing, and so I specified the axes: app.UIAxes. This does not seem to work, and I get the following error: "Error using images.roi.internal.ROI/parseInputs
ROI parent must be a valid Axes object.".
I am using R2019a of MATLAB.