/** Initialize widgets of the main panel. */
 private void attrInit() {
   submitSpeedBtn = (Button) findViewById(R.id.submitEntrSpeed);
   submitSpeedBtn.setOnClickListener(new SubSpeedButtonListener());
   submitIntervalBtn = (Button) findViewById(R.id.submitExitSpeed);
   submitIntervalBtn.setOnClickListener(new SubIntervalButtonListener());
   editSwitchSpeed = (EditText) findViewById(R.id.editEntrSpeed);
   editInterval = (EditText) findViewById(R.id.editExitSpeed);
   // Set default values, for users.
   // editSwitchSpeed.setText("20");
   // editInterval.setText("30");
   // Set default values, for testing.
   editSwitchSpeed.setText("20");
   editInterval.setText("1");
   auto.setSwitchSpeed(Integer.valueOf(editSwitchSpeed.getText().toString()).intValue());
   auto.setInterval(Integer.valueOf(editInterval.getText().toString()).intValue());
   cbSwi = (CheckBox) findViewById(R.id.cbSwitch);
   cbSwi.setOnCheckedChangeListener(new SwiCBListener());
   cbRib = (CheckBox) findViewById(R.id.cbRib);
   cbRib.setOnCheckedChangeListener(new RibCBListener());
   tvSSTitle = (TextView) findViewById(R.id.tvSSTile);
   tvITitle = (TextView) findViewById(R.id.tvITile);
   tvExit = (TextView) findViewById(R.id.tvExit);
   tvSSTitle.setOnClickListener(new TextViewListener());
   tvITitle.setOnClickListener(new TextViewListener());
   tvExit.setOnClickListener(new TextViewListener());
 }
 /**
  * Rewrite function Destroy, called when the object of class NetMngActivity deleted. In addition
  * to default operations, turn off automatic management and unregister broadcast receiver.
  */
 @Override
 public void onDestroy() {
   super.onDestroy();
   if (auto.isAuto()) auto.offAuto();
   this.unregisterReceiver(broadcastReceiver);
 }