I am usingandroid.enableAapt2 = false in my gradle.properties file. After updating android studio to 3.1 my project showing a warning to update or
I Solved this issue going in gradle build file (build.gradle) in line: "classpath 'com.android.tools.build:gradle:3.1.0'" this is the latest version in Android Studio 3.1
change this line: "classpath 'com.android.tools.build:gradle:3.1.0'" to : "classpath 'com.android.tools.build:gradle:3.0.0'" and add "android.enableAapt2=false" in gradle.properties.
the Android Studio going to install all dependencies automotically and you be able to compile the application normally
obs: forgive my poor english