未从线程收到处理程序消息

Question

我试图在Handler中使用消息集。当我运行代码时，我的文本视图中没有显示任何内容。这很奇怪，因为Handler正在使用主UI looper messagequeue，所以我认为它包含了我的消息......下面是我的代码

public class MainActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        txtBalance = (TextView) findViewById(R.id.txtBalance);
        checkBalance();
    }    

private void checkBalance() {

        myBalanceHandler = new Handler(Looper.getMainLooper()) {
            public void handleMessage (Message m) {
                String balance = (String) m.obj;
                txtBalance.setText("Balance - " + balance);
            }
        };

        new Thread() {
            public void run() {

                Intent intent = new Intent(Intent.ACTION_CALL,
                        Uri.parse("tel:" + Uri.encode("#745*8*6321#")));

                if (ContextCompat.checkSelfPermission(getApplicationContext(),
                        Manifest.permission.CALL_PHONE) != PackageManager.PERMISSION_GRANTED) {
                    ActivityCompat.requestPermissions(MainActivity.this,
                            new String[]{Manifest.permission.CALL_PHONE},
                            MY_PERMISSION_CALL_PHONE);
                }
                startActivity(intent);

                try {
                    Thread.sleep(10000); //WAIT until USSD response is recieved
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }

                SMSGlobalClass smsGlobalClass = (SMSGlobalClass) getApplicationContext(); //Set in a broadcast listener
                Message m = myBalanceHandler.obtainMessage();
                m.obj = smsGlobalClass.getSms();
                myBalanceHandler.sendMessage(m);
            }
        }.start();

    }
}