When running flutter pub get (Packages get in IntelliJ or Android Studio) for the first time after adding a package, Flutter saves the concrete package version found in the pubspec. lock lockfile. This ensures that you get the same version again if you, or another developer on your team, run flutter pub get .
Read moreWhat does flutter pub upgrade do?
Upgrade is one of the commands of the pub tool. Like dart pub get , dart pub upgrade gets dependencies . The difference is that dart pub upgrade ignores any existing lockfile, so that pub can get the latest versions of all dependencies.
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