How to show the System Navigation bar in an Android Emulator

1. Open Android Studio

2. Click Tool Button

3. Click Android 

4. Click SDK Manager

5. Then again click Tools in the top 

6. Go to Manage AVDs 

7.  Select Your Emulator

8. And Edit Button on right side

9. Then Look Below Screenshot image and do same Setting, don't forget to select
Skin: HVGA

10. And Restart your Android Studio