在导入Google项目之后，点击分析 - >点击Android图标，出现以下屏幕：

名称和SHA-1。下载google-services.json并移动到你的/ app /文件夹（path-to-app / app / google-services.json）。

它必须工作！

Pressing the following button is giving the error below the image.

Firebase
No clients were able to be added to your Firebase project for the following reasons:
An app with this package name and SHA1 is already connected to a Google project. If you have used a Google API previously, please select that project in the Connect to an existing Project list. 
Client Package Name: packagename
Client SHA1: [59:17:0C:D9:63:14:42:A5:81:13:20:F8:58:0F:96:D8:6A:65]

I could not find the Connect to an existing Project list mentioned in the error message.

I created the project in firebase by clicking "Import Google Project" button and selecting an existing google project. Later i tried adding both debug and production signature SHA1's but that did not help.

anyone faced the same issue?

EDIT: Today the existing project list dialog started appearing but i still get the error even if i select from the existing project list. I started thinking that this is a preview bug. :(

After "Import Google Project". Click Analytics->Click Android Icon and the following screen appears.

Put your app package name and SHA-1. Download google-services.json and move to your /app/ folder. (path-to-app/app/google-services.json).

It must work!