问题
Upon reopening Android Studio after an improper shutdown, my gradle project sync failed and many errors like: "Failed to resolve: junit:junit:4.12" started showing up in the Event Log. Screenshot is given below.
I tried the following things to no avail:
- Updated Android Studio to ver 2.3.1 and thus also the Gradle
- I also had error for "Plugin Error: required plugin "xyz" is disabled" so i deselected all the plugins showing errors from settings and reselected them which removed the error.
- Then i went to Files -> Invalidate caches/restart
What should i do?
UPDATE: After clicking on "Disable offline mode and sync project", this is what happened.
回答1:
From your first screenshot
Gradle is in offline mode, which means that it won't go to the network to resolve dependencies.
Go to Preferences > Gradle and uncheck "Offline work".
After that try cleaning the project and Re-running again?
回答2:
Here is a working solution..
Step 1) In Android Studio go to File > Project Structure
there unticheck "Use Embedded JDK" and below choose your JDK location..
Step 2)
Go to file gradle > wrapper > gradle-wrapper-proparties change gradle version to 3.5-all
Step 3) close the project and reopen
回答3:
What worked for me;
Go to Preferences > Gradle & uncheck "Offline work"
Goto File > Invalidate caches and restart.
The project would restart and can begin to install dependencies. Dont worry if it takes a time, that could be due to slow network. Just go and sip coffee while you wait ;)
来源：https://stackoverflow.com/questions/43447360/gradle-project-sync-failed-in-android-studio-2-3-1