Shaking hands post stroke

This is a major problem, at some of the more formal events I get introduced and am expected to shake hands. Normally I have a glass of wine in my good hand. Normal people just switch the wine glass to the left hand, shake and go on. Either I have to decline and embarrassingly state the reason why. Or sometimes I'll extend my first and second fingers hoping that the rest of my hand can control the wine glass. Or I hand the glass to the introducer, shake hands and go on. Sometimes I'm forced to put the glass on the floor. I try my best to never advertise my disabilities, I want no pity or condescension. My left hand has no chance of holding any kind of glass upright. I should be able to go to a publicly available stroke rehab database where this common ADL and other problems are described with concrete solutions to every one.