custom 'Keyboard +Mouse' Callback creation

Dear All,

I am using Matlab 2018a. I need to create essentially a custom ButtonDownFcn, consistent of ALT key + left mouse click.

I find that the 4 types of 'SelectionType' property do not allow such custom fct. ALT key press would act as a filter to the mouse click (I cannot use Ctrl or Shift because they are already used in other tasks.

Thank you,

Octavain