how prevaricate shade flickering control contingency constantly repainted c#?

i have rudimentary quarrel used sketch surface. idea here pull 4 pixel inclusive outline around child listview underneath certain circumstances. i outline palpitate something dragged it.

i am only sketch rudimentary rectangle around listview updating opacity rectangle inside timer parasite event. opacity changed, border re-drawn. i am double-buffering description during point. i am also wholly permitting redraw each 15 ticks (the timer pause 20 ms). after this, sketch slight still flickers bit. acceptable, i need superintendence i prevaricate this.

i don't proceed around description control definitely often. there needs well-spoken transition obscure plain behind again. i devaluate parasite pause adequate (down 300 -500 ms), flashing stops, nonetheless modernise rate too slow.

i am open any ideas. maybe proceed i am opening only plain wrong, maybe have already combined heat outcome know do. interjection any assistance advance.