问题
I'm trying to run my mobile app in the Android Emulator from Android Studio. When I run the app, it prompts me to select the emulator instance:
When I select an emulator instance the build of the application starts and the emulator selected boots up.
After the build completes, Android Studio tells me that its "waiting for the target device to come online" so that it can authenticate with the bridge.
After waiting for some time, I do not get an "Allow USB Debugging" confirmation with an RSA thumbprint so I enable developer mode and go into the settings.
I then try and turn the setting "USB Debugging" off and then back on, I then restart the ADB service on my computer which results in the ADB service asking me to authorise the device (which I cant get the confirmation for)
I have tried this with a few other Android versions, which of only one has worked (API 27) (This version showed me the allow confirmation window as soon as the OS booted) I also checked to see if developer options were enabled on the working OS (API 27), they were not which indicates that the OS images are pre-configured as they are emulators and I shouldn't need to touch any of the settings.
This feels like its an image problem as one of the images (API 27) does work. Does anyone know why I cannot get the other API versions to give me a prompt to authenticate with the remote target?
One thing to note:
On the versions that do not work, I cannot see a USB port on the device under Developer Options -> Select USB configuration but on the one working image I can see the USB port is detected and is set to "Charging".
API 27 (The image that works):
API 25 (An image that does not work):
This is the prompt I expect to see so that the ADB service can communicate with the device:
回答1:
I was also facing same problem, but solved by wiping data and killing and restarting the adb server, but it also not worked for again* So , I used
Emulaor with no Play support
it only solved mine. Hope it will be helpful to anybody else
来源：https://stackoverflow.com/questions/55278692/android-emulator-instance-does-not-show-allow-usb-debugging-confirmation-to-au