短信备份的原理


短信备份的原理。是用内容提供者读取短信，然后保存。

public class SmsBackupUtils {

  // 回调接口
  public interface SmsBackupCallback {
    /**
     * 短信备份前调用
     * @param total    短信的总条数
     */
    public void beforeSmsbackup(int total);

    /**
     * 短信调用中调用
     * @param progress  短信的进度
     */
    public void progressSmsbackup(int progress);
  }

  /**
   * 短信备份的方法,备份到xml文件里,由于xml文件跨平台性强  这是一个耗时操作,应该放在子线程中运行
   * 
   * @param context 上下文
   * @param path 备份到哪个路径
   * @throws Exception
   */
  public static void smsBackup(Context context, String path,SmsBackupCallback callBack) throws Exception {

    // xml的序列化器
    XmlSerializer serializer = Xml.newSerializer();
    File file = new File(path);
    FileOutputStream fos = new FileOutputStream(file);
    // 设置參数
    serializer.setOutput(fos, "utf-8");
    // 開始
    serializer.startDocument("utf-8", true);
    serializer.startTag(null, "smss");

    ContentResolver resolver = context.getContentResolver();
    Uri uri = Uri.parse("content://sms");// 包括全部短信
    Cursor cursor = resolver.query(uri, new String[] { "address", "date",
        "type", "body" }, null, null, null);

    /*dialog.setMax(cursor.getCount());
    progressBar1.setMax(cursor.getCount());*/
    callBack.beforeSmsbackup(cursor.getCount());
    int progress = 0;
    while (cursor.moveToNext()) {
      serializer.startTag(null, "sms");

      serializer.startTag(null, "address");
      String address = cursor.getString(0);
      serializer.text(address);
      serializer.endTag(null, "address");

      serializer.startTag(null, "date");
      String date = cursor.getString(1);
      serializer.text(date);
      serializer.endTag(null, "date");

      serializer.startTag(null, "type");
      String type = cursor.getString(2);
      serializer.text(type);
      serializer.endTag(null, "type");

      serializer.startTag(null, "body");
      String body = cursor.getString(3);
      serializer.text(body);
      serializer.endTag(null, "body");

      serializer.endTag(null, "sms");
      progress++;
      /*dialog.setProgress(progress);
      progressBar1.setProgress(progress);*/
      callBack.progressSmsbackup(progress);

      SystemClock.sleep(1000);
    }
    cursor.close();

    serializer.endTag(null, "smss");
    serializer.endDocument();
  }
}