Waiting for Target Device to Come Online

I too had the same problem, then I went to AVD manager and right click on the emulator and stopped it and I RUN the application again and this time it worked. It may be a temporary solution but works for the time being.

Tools -> AVD manager -> right-click on the emulator you are using -> Stop

Now Run your application again.

Note: Sometimes closing the emulator directly is not working for the above-mentioned problem but stopping it from the AVD manager as mentioned is working.

Following worked for me on Android Studio 3.x.

Step 1: Open AVD Manager.

Step 2: Right click and Wipe data for the virtual device you're testing on.