how to perform all tasks at the same time? [closed]

I can not get it to execute all these tasks at the same time, it only executes the rest when it receives some data in InputStream . And after receiving this data he does not receive any more. Help me please, I'm newbie and I've tried several examples but I can not get it to work.

package com.vaiporra;

import android.app.Activity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.os.Bundle;
import android.os.SystemClock;

import android.view.View;
import android.widget.Button;
import android.widget.Chronometer;

import android.widget.Toast;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.UUID;
import java.io.IOException;



public class MainActivity extends Activity{

    Button btDireita; 
    Button btEsquerda;
    Chronometer crono1;
    char serial;
    BluetoothAdapter bluetooth = BluetoothAdapter.getDefaultAdapter();
    private BluetoothDevice dispositivoBluetoohRemoto;
    private BluetoothSocket meuSocket;
    private OutputStream outputStream=null;
    private InputStream inputStream = null;
    private static final String MAC = "60:BE:B5:7A:FD:49";
    private static final UUID MEU_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        if (!bluetooth.isEnabled()) {
            bluetooth.enable();
        } 

        conecta();

        ChamaPrincipal();
    }

    private void ChamaPrincipal() {
        setContentView(R.layout.activity_main);

        crono1= (Chronometer)findViewById(R.id.crono1);

        crono1.setBase(SystemClock.elapsedRealtime());

        crono1.start();

        btEsquerda = (Button)findViewById(R.id.button1);

        btEsquerda.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                try{
                    outputStream = null;
                    outputStream = meuSocket.getOutputStream();
                    outputStream.write('a');

                    Toast.makeText(getApplicationContext(), "Mensagem foi enviada", Toast.LENGTH_LONG).show();
                } catch(IOException e){
                    Toast.makeText(getApplicationContext(), "Mensagem não recebida", Toast.LENGTH_LONG).show();

                }
            }
        });
        btDireita = (Button)findViewById(R.id.button2);

        btDireita.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                try{
                    outputStream = null;
                    outputStream = meuSocket.getOutputStream();
                    outputStream.write('b');

                    Toast.makeText(getApplicationContext(), "Mensagem foi enviada", Toast.LENGTH_LONG).show();
                } catch(IOException e){
                    Toast.makeText(getApplicationContext(), "Mensagem não recebida", Toast.LENGTH_LONG).show();

                }
            }
        });
        try{
            while(true){

                inputStream = meuSocket.getInputStream();
                serial = (char) inputStream.read();

                if(serial == 'a'){
                    chamaPQP();
                }
                else if(serial == 'b'){
                    chamaTNC();
                }
                else{
                     Toast.makeText(getApplicationContext(), "Manda outro", Toast.LENGTH_SHORT).show();
                }
         }}
        catch(Exception e){}

    }

    private void chamaTNC() {
        setContentView(R.layout.tnc);

    }

    private void chamaPQP() {
        setContentView(R.layout.pqp);

    }

    public void conecta(){
        if(BluetoothAdapter.checkBluetoothAddress(MAC)){
            dispositivoBluetoohRemoto = bluetooth.getRemoteDevice(MAC);
        } else{ 
            Toast.makeText(getApplicationContext(), "Endereço MAC do dispositivo Bluetooth remoto não é válido", Toast.LENGTH_SHORT).show();
        }

        try{
            meuSocket = dispositivoBluetoohRemoto.createRfcommSocketToServiceRecord(MEU_UUID);

            meuSocket.connect();

            Toast.makeText(getApplicationContext(), "Conectado", Toast.LENGTH_SHORT).show();

        } catch(IOException e){
            Toast.makeText(getApplicationContext(), "Conexão não foi estabelecida", Toast.LENGTH_SHORT).show();
        }
    }       
}