What I see is an attempt to dispel the the consequences of his racism. He's not trying to get black voters he is trying to reach white voters who might be leery of voting for a blatant racist what ever Trump does because of his M.O. I attribute the worst possible motive He is crook(criminal), phony , liar, Oh, I could go on and on. I hope he can be stopped!Somebody taught thesecreeps to do stuff like this. I wonder who?

Trying to get elected for an 2nd term. He don't care about them or anybody else that he feels is beneath him.

The only antidote to this is to push Obama's achievements on to every Trump address where black peoples are present.
Trump would rather choke than praise, even faintly, anything Obama did. This tactic would alienate most black voters to Trump.

Its democracy, it works because people have short memories. In the first year you are nasty, in the second you line your pockets, and in the third you start being nice to everyone. It only has to work with enough floating voters to tip the balance, and you can get away with anything. People just don't pay attention.

Getting re-elected, he is dragging every conservative minority out of the closet he knows. Sadly, they exist.

Smoke and mirrors distraction from his racism