您需要检查以下事项:

1.你在google api console注册的SHA1指纹是否可以.关于如何找到它，你可以找到它此处

2. 生成的api_key必须与menifest一致.

3. api控制台中的应用名称必须与strings.xml中的应用名称一致.

4. meta-data 必须包含在 menifest 中.

There are some things you need to check:

1. Is the SHA1 fingerprint is ok that you have registered in google api console.For how to find it , you can find it here

2. The generated api_key must be same with the menifest.

3. Name of the app in api console must be same with the name of app in strings.xml.

4. meta-data must have to be included in menifest.

<meta-data 
             android:name="com.google.android.gms.version"
             android:value="@integer/google_play_services_version" />

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