My dog was blind in both eyes. She loved to do tricks when she was blind in one eye. She had glaucoma which had progressed to both her eyes. Once she became blind in both eyes, she did not enjoy alot of activites she use to. Like us humans, dogs become depressed after losing eyesight. Some dogs do perfectly fine blind, others like my dog suffer from it. She was in terrible pain and I could not afford to remove her eyes [which was needed with the severity of her case] so I had to put her down. If the money was there I would of still have my baby girl, blind and no eyes, she would of still been the love of my life. She did fairly good blind, she knew her way around the house without bumping into things. But what made me realize she wasn't the same was when she would go on walks. When you mentioned the word 'walk' she would be the happiest dog ever, when she became blind, she couldn't care less. We still went on short walks, but she felt very insecure and not enjoying them as much as she did. She spent most the time sleeping on her dog bed. But again many dogs do very well blind, just a bit insecure than dogs that can see.
Here she is performing some tricks [not a handstand or anything] when she was blind in one eye. BTW she wasn't a yorkie

Sorry about the quality of the video. I miss that little wagging tail.