How do I fix errors in Android Studio?

layout error is being caused by a mismatch between Android Studio’s cache and your project’s current layout. If you suspect this may be the case, then select File > Invalidate Caches / Restart > Invalidate and Restart from Android Studio’s toolbar. Issues with the names of your resources can also prevent the R.

Where can I see errors in Android Studio?

In addition to what the other answers say, you can find errors by pressing F2 or Shift + F2 . This is useful when you can’t see the where the red indicator is on the side bar.