how to using keyboard to select data in treeview without mouse

Question

Firstly, When my cursor is in the entry box (entrybox.focus()), I would like to using F4 key on keyboard (GUI.bind('<F4>', directselection)) to select the first data in my treeview directly instead of using mouse.

I don't have any idea to create the function. I'm trying to use

def directselection(event = None):
    treeviewtable.focus()

but it doesn't work.

Answer 1

Use .get_children() to get a list of row IDs and then use .selection_set() to select the first row:

def directselection(event=None):
    # get all row IDs
    idlist = treeviewtable.get_children()
    if idlist:
        # select and focus on first row
        treeviewtable.selection_set(idlist[0])
        treeviewtable.focus(idlist[0])
        # transfer keyboard focus to treeviewtable
        treeviewtable.focus_force()