Update Gradle in Flutter project

Here is how I upgraded gradle in my older Flutter project:

1. Create a new temp project with the latest version of Flutter. You’ll use this to see what version of gradle Flutter is using nowadays.

2. In the temp project open android/build.gradle check the classpath version of gradle being used and update that in your old Flutter project. For me today it looks like this:

   classpath 'com.android.tools.build:gradle:4.1.0'
   

3. In the temp project open android/gradle/wrapper/gradle-wrapper.properties and check the distributionUrl. Update your old project to use the same one. For me today it looks like this:

   distributionUrl=https\://services.gradle.org/distributions/gradle-6.7-all.zip
   

4. Rerun your app. It has to download the new version of gradle to the android/.gradle directory so the first time might take a while.