如何在android应用程序中以编程方式备份gmail的exchange帐户

<uses-permission android:name="android.permission.GET_ACCOUNTS" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

Account[] accounts = AccountManager.get(context).getAccounts();
Account gmailAccount = null;

for (Account account : accounts) {
    if (account.type.equals("com.google.exchange")) {
        gmailAccount = account;
        break;
    }
}

ContentResolver contentResolver = context.getContentResolver();
Uri uri = Uri.parse("content://com.android.exchange.provider/mailbox");
String[] projection = { "_id", "displayName", "serverId" };
String selection = "accountKey=?";
String[] selectionArgs = { gmailAccount._id };

Cursor cursor = contentResolver.query(uri, projection, selection, selectionArgs, null);

if (cursor != null && cursor.moveToFirst()) {
    do {
        // 备份每个邮箱的数据
        String mailboxId = cursor.getString(cursor.getColumnIndex("_id"));
        String displayName = cursor.getString(cursor.getColumnIndex("displayName"));
        String serverId = cursor.getString(cursor.getColumnIndex("serverId"));

        // 备份代码...
    } while (cursor.moveToNext());

    cursor.close();
}

String backupData = "备份数据"; // 替换为实际的备份数据
String fileName = "gmail_backup.txt"; // 替换为实际的文件名

try {
    FileOutputStream fos = context.openFileOutput(fileName, Context.MODE_PRIVATE);
    fos.write(backupData.getBytes());
    fos.close();
} catch (IOException e) {
    e.printStackTrace();
}