通过蓝牙向我的arduino发送1个字符和1个整数时数据错误

Question

我目前正在使用Android手机将我的项目通过蓝牙发送到arduino，当我选择旋转器的项目时我只发送1个字符时没问题。但是，当发送一个字符然后发送一个整数时，它不起作用。 android spinner用于向arduino发送数据：

spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
            if (btSocket != null) {
                switch (position) {
                    case 0:
                        msg("In ed!");
                        break;
                    case 1:
                        try {
                                btSocket.getOutputStream().write("m".toString().getBytes());
                                btSocket.getOutputStream().write(Integer.toHexString(1).getBytes());
                        } catch (IOException e) {
                                msg("Error1");

                        }
                        break;
                    case 2:
                        try {
                            btSocket.getOutputStream().write("m".toString().getBytes());
                            btSocket.getOutputStream().write(Integer.toHexString(2).getBytes());
                        } catch (IOException e) {
                            msg("Error2");
                        }
                        break;
                    case 3:
                        try {
                            btSocket.getOutputStream().write("m".toString().getBytes());
                            btSocket.getOutputStream().write(Integer.toHexString(3).getBytes());
                        } catch (IOException e) {
                            msg("Error3");
                        }
                }
            }
        }

        @Override
        public void onNothingSelected(AdapterView<?> parent) {
            // sometimes you need nothing here
        }
    });
}

arduino代码：

char data;            //Variable for storing received data
int blueVal;
void setup()
{
    Serial.begin(9600);   //Sets the baud for serial data transmission                               
}
void loop()
{
   if(Serial.available() > 0)      // Send data only when you receive data:
   {
      Serial.println("Begin receiving");
      data = Serial.read();        //Read the incoming data & store into data
      blueVal = Serial.read();
      Serial.println(data);          //Print Value inside data in Serial monitor 
      Serial.println(blueVal);      

   }
}`

微调器选择微调器的第一项时的结果：

Begin receiving 
 m
-1 
Begin receiving
 1
-1

arduino收到两次数据和未知的＆＃39; -1＆＃39;数据，结果应该是：

Begin receiving
m
1

感谢您的帮助！