title: Android 5.0 data usage TrafficStats.GetUidTxBytes return incorrect value
body: <p>I want to let the user check the app's data usage inside my app. So I use </p>
  
  <pre><code>float dataRX= (float)TrafficStats.GetUidRxBytes(Android.OS.Process.MyUid())/(float)(1024*1024);
  float dataTX= (float)TrafficStats.GetUidTxBytes(Android.OS.Process.MyUid())/(float)(1024*1024);
  </code></pre>
  
  <p>to get the Rx bytes and the Tx bytes. This works fine at Android 4.x. However, When I test my app at Android 5.0, these two function will return very huge numbers which is definitely incorrect. I check the system setting, my app only consume 800kb. So how can I get the correct data usage in Android 5.0?</p>