queryComment.java

private void queryComment() {
        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    if (mAccessToken == null) {
                        Log.d(TAG, "need to sign in first");
                        return;
                    }
                    if (fileSearched == null) {
                        Log.d(TAG, "query file first");
                        return;
                    }

                    Drive drive = buildDrive();
                    CommentList response = drive.comments()
                            .list(fileSearched.getId())
                            .setFields("comments(id,description,replies(description))")
                            .execute();

                    final String text = response.getComments().toString();
                    MainActivity.this.runOnUiThread(new Runnable() {
                        @Override
                        public void run() {
                            tv_comments.setText(text);
                        }
                    });

                    Log.d(TAG, "query comments success");
                } catch (Exception e) {
                    Log.d(TAG, "query comments failed " + e.toString());
                }
            }
        }).start();
    }