Background turned black while trying to catch a rattata

I clicked on the rattata on the map and it did the small intro animation after that the background on the catch screen, I don't use AR, turned black from the bottom to the top. The rattata was still visible and jumped up and down and thw circle also still worked. However all other icons including the Pokeball vanised.

I didn't manage to reproduce this, so I don't know what caused it. The only way to fix it was to restart the app. Has anyone encountered something similar, or knows the cause?

pokemon-go

Best Answer

To explain what is actually occurring:

The ball is getting stuck under the Rattata's body when you toss it so quickly, which causes it to glitch through the floor. This can also happen with Weedle and likely other Pokémon that start the battle very close to you.

The math used to draw the shadow of the Pokéball onto the ground will decrease the size of the shadow the higher the Pokéball goes and increase it as the Pokéball gets lower. When the Pokéball goes through the floor, it falls infinitely in the void and the size of the shadow continues to get larger and larger, forever.

Since the ball doesn't collide with the floor, the game doesn't consider it a completed throw. A throw is completed when the ball collides with the Pokémon or the floor, after which it animates for about a second longer before selecting your next Pokéball. The only solution is to restart your app and curse at the Rattata.