Upload files using Android Google Drive api?

Google official documents and

https://github.com/gsuitedevs/android-samples/blob/021e756d763614d1f57c953083f8392f7189b686/drive/demos/app/src/main/java/com/google/android/gms/drive/sample/demo/CreateFileActivity.java

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I just want to upload the file, but I can't find the example

I don't know how

Does anyone know? ㅠ<

No matter how many times I search for it, I don't know

The purpose is to upload a backup db file, but there is nothing related to it in the official demo file.

Masters, please help me~~~