Error running All Tests: Gradle projectsync failed. Please fix your project and try again. How to solve?
First, a two-week solution was found online:
Plan 1: Since Gradle is suggested, start with this batch. What is Gradle?Please poke here: click open link
1. The File – & gt; Invalidate caches/Restart
2. The Shutdown Android Studio
3. Rename/remove. Gradle Folder in the user Home Directory
4 Restart Android Studio let it Download all the Gradlestuff it Needs
Gradle Build Success!
6. Rebuild project… success !
 
Scheme 2:
File -> Settings Search for Gradle, make the following changes (specify the location of Gradle to be downloaded manually), For Gradle download, please stamp here: click open link

Solution 3:
The above method didn’t work, so I killed gradle and Gradle in the project directory, created a new project, copied the two folders in the new project, and the Studio returned to normal.

In addition to the above methods, based on personal experience can also be:
This can also happen if a project developed on an original device is about to be moved to another device (the gradle update download is very slow)
At this point, first go to the Settings of Android Studio under the new device and turn off the Proxy

Then go to the directory of Gradle

Use the.gradle directory for the original device instead of the gradle directory for the new device.