title: Difference between CONNECTION_STATE_CHANGED and STATE_CHANGED
body: <p>What's the difference between Action CONNECTION_STATE_CHANGED and STATE_CHANGED in Android Bluetooth Receiver ?</p>
  
  <pre><code>            else if (BluetoothAdapter.ACTION_CONNECTION_STATE_CHANGED .equals(action)) {
              int state = intent.getIntExtra(BluetoothAdapter.EXTRA_CONNECTION_STATE,
                      BluetoothAdapter.STATE_DISCONNECTED);
                  if (state == BluetoothAdapter.STATE_CONNECTED) {
                      //nothing
                  } else {
  
                  }
          } else if (BluetoothAdapter.ACTION_STATE_CHANGED.equals(action)) {
              int state = intent.getIntExtra(BluetoothAdapter.EXTRA_STATE, BluetoothAdapter.ERROR);
              if (state == BluetoothAdapter.STATE_OFF) {
  
              }
          }
  </code></pre>