1) We have the same issue as this https://community.clover.com/questions/18789/paymentconnector-is-not-launching-payment-screen.html
2) The link in the answer is wrong, use https://community.clover.com/questions/18487/paymentconnectorsale-is-not-reliably-launching-the.html instead.
3) The issue described here https://community.clover.com//questions/18487/paymentconnectorsale-is-not-reliably-launching-the.html is pretty similar to ours. We also are AT A DEAD END!
4) People still having similar issues https://community.clover.com/questions/15582/paymentconnectorsale-does-not-show-the-display-scr.html
We followed the exact same steps described in here https://docs.clover.com/clover-platform/docs/take-a-payment-with-payment-connector without success! The same issue described in 2) is happening to us. The async task is not being executed and clicking on the sale button does nothing!
You can check our code here https://bitbucket.org/pabloleone/test-clover-android-app/src/master/
It's public because it's just what the example describes we are not trying to do anything special, just collect a single payment.
Could you help us?