Both of these foods are wrong. He scarfs them down because these frogs are gluttons and will eat anything that will fit in their mouth. This doesn't mean its good for him though. Lol.
A good staple diet for African Clawed frogs is Tetra's Reptomin. You'll want to break it into pieces for him though. Another choice is a specially formulated food you can find on xenopus.com. Other good things to feed him are tubifex worms, earthworms (farm raised to prevent disease and parasites), some people feed them raw trout, salmon, and tilapia. You can even feed them feeder guppies. Do NOT feed bloodworms, beefheart, or mealworms as these can all cause disease or impaction for your frog. Other fish like goldfish should not be given to your frog either. Other people have said that canned crickets have given them problems with their frogs as well that has lead to death, so these are best avoided as well.