AsyncTask小结

new AsyncTask<Void, Void, Void>() {        @Override        protected void onPreExecute() {            mLoadingView.setVisibility(View.VISIBLE);        }        @Override        protected Void doInBackground(Void... params) {            mDatas = TrafficProvider.getTraffics(TrafficActivity.this);            return null;        }        @Override        protected void onProgressUpdate(Void... values) {        }        @Override        protected void onPostExecute(Void result) {            mLoadingView.setVisibility(View.GONE);            mLv.setAdapter(new TrafficAdapter());        }    }.execute();

---

    // 加载进度条    final ProgressDialog dialog = new ProgressDialog(this);    dialog.setCancelable(false);    dialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);    SmsProvider.smsBackup(this, new OnSmsListener() {        @Override        public void onPre() {            dialog.show();        }        @Override        public void onProgress(int max, int progress) {            dialog.setMax(max);            dialog.setProgress(progress);        }        @Override        public void onFinish(boolean success) {            dialog.dismiss();            if (success) {                Toast.makeText(CommonToolActivity.this, "备份成功", 0).show();            } else {                Toast.makeText(CommonToolActivity.this, "备份失败", 0).show();            }        }    });public static void smsBackup(final Context context,        final OnSmsListener listener) {    new AsyncTask<Void, Integer, Boolean>() {        @Override        protected void onPreExecute() {            if (listener != null) {                listener.onPre();            }        }        @Override        protected Boolean doInBackground(Void... params) {            boolean flag = true;            try {                // 读短信,放到sd卡中                ContentResolver cr = context.getContentResolver();                Uri uri = Uri.parse("content://sms");                String[] projection = { "address", "date", "read", "type",                        "body" };                String selection = null;                String[] selectionArgs = null;                String sortOrder = null;                // select * from table where name = 'zs';                Cursor cursor = cr.query(uri, projection, selection,                        selectionArgs, sortOrder);                // 放到list中                List<SmsBean> list = new ArrayList<SmsBean>();                if (cursor != null) {                    int count = cursor.getCount();                    int progress = 0;                    publishProgress(count, progress);                    while (cursor.moveToNext()) {                        String address = cursor.getString(0);                        long date = cursor.getLong(1);                        int read = cursor.getInt(2);                        int type = cursor.getInt(3);                        String body = cursor.getString(4);                        SmsBean bean = new SmsBean(address, date, read,                                type, body);                        list.add(bean);                        publishProgress(count, ++progress);                    }                }                cursor.close();                // json到sd卡中                Gson gson = new Gson();                String json = gson.toJson(list);                BufferedWriter bw = null;                try {                    bw = new BufferedWriter(new FileWriter(new File(                            Environment.getExternalStorageDirectory(),                            "sms.json")));                    bw.write(json);                } catch (Exception e) {                    e.printStackTrace();                } finally {                    StreamUtils.closeIO(bw);                }            } catch (Exception e) {                flag = false;            }            return flag;        }        @Override        protected void onProgressUpdate(Integer... values) {            Integer max = values[0];            Integer progress = values[1];            if (listener != null) {                listener.onProgress(max, progress);            }        }        @Override        protected void onPostExecute(Boolean result) {            if (listener != null) {                listener.onFinish(result);            }        }    }.execute();}