You will need to use the command send()using a tree descriptor, an event identifier (vscroll = 277), a flag, to tell it. HOW to scroll (up one line, down one line, up page, down page, etc.), and then another long value, which is the identifier of the line or message (not used here)
So, to scroll one line, you should use:
Send(Handle(tv_1), 277, 0, 0)
, :
Send(Handle(tv_1), 277, 1, 0)
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