Switch switchTest = (Switch) findViewById(R.id.switch1);
switchTest.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
 @Override
 public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
  if (isChecked) {
   mBluetoothAdapter.enable();//打开蓝牙
  } else {
   mBluetoothAdapter.disable();// 关闭蓝牙
  }
 }
});

Button btn = (Button) findViewById(R.id.button);
btn.setOnClickListener(new View.OnClickListener() {
 @Override
 public void onClick(View view) {
  Toast.makeText(MainActivity.this, "bluetooth is " +bluetoothStatus,
    Toast.LENGTH_SHORT).show();
 }
});

<uses-permission android:name="android.permission.BLUETOOTH"/>
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>

//注册蓝牙监听
mContext.registerReceiver(mReceiver, makeFilter());
//注销蓝牙监听
//mContext.unregisterReceiver(mReceiver);
private IntentFilter makeFilter() {
  IntentFilter filter = new IntentFilter();
  filter.addAction(BluetoothAdapter.ACTION_STATE_CHANGED);
  return filter;
}
private BroadcastReceiver mReceiver = new BroadcastReceiver() {
  @Override
  public void onReceive(Context context, Intent intent) {
   switch (intent.getAction()) {
    case BluetoothAdapter.ACTION_STATE_CHANGED:
     int blueState = intent.getIntExtra(BluetoothAdapter.EXTRA_STATE, 0);
     switch (blueState) {
      case BluetoothAdapter.STATE_TURNING_ON:
       Log.e("TAG", "TURNING_ON");
       break;
      case BluetoothAdapter.STATE_ON:
       bluetoothStatus="on";
       Log.e("TAG", "STATE_ON");
       break;
      case BluetoothAdapter.STATE_TURNING_OFF:
       Log.e("TAG", "STATE_TURNING_OFF");
       break;
      case BluetoothAdapter.STATE_OFF:
       bluetoothStatus="off";
       Log.e("TAG", "STATE_OFF");
       break;
     }
     break;
   }
  }
};