Launcher off/on saying saying i'm offline.

Tried opening the launcher and the bar at the bottom saying i'm offline kept showing up and going away repeatedly. I have internet connection, and wanted to play on a server.
I tried logging out and logging back in, and uninstalling and re-installing the launcher. I am still having this issue and now I can't even start the game because it wants me to type in a username, but the box that lets me type a username keeps flashing away because the boxes saying I am online keep flashing in front of it.