In a large mixing bowl, combine first 7 ingredients and gently mix to combine. Be sure the corn is drained and the black beans are drained and throughly rinsed until water runs clear.
Then in a separate small bowl, mix the lime juice, olive oil and season with salt and pepper. Place it in your refrigerator and allow to marry for at least 30 minutes
Remove from fridge and just prior to serving add the chopped avocado.