局部变量onChronometerTick效率低下？

Question

这是我的活动的简化版本。我有一个计时器，每秒都会调用onChronometerTick。在方法中声明和初始化局部变量会不会有效？

或者更好的做法是在方法之外声明变量，只是在onChronometerTick内部更改它们的值

public class MainActivity extends Activity implements Chronometer.OnChronometerTickListener {


    //Declaring View Variables
    private Chronometer timer; //The timer

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


        //Initialising View Variables
        timer = ((Chronometer)findViewById(R.id.chronometer));
        timer.setOnChronometerTickListener(this);
    }

    public void onChronometerTick(Chronometer chronometer) {

        //Local variables
        String timerTime = (chronometer.getText()).toString();  //Gets the string value of the timer

        Boolean stop = false;
        Boolean halfTime = false;
        Boolean fullTime = false;

        switch (timerTime){

            case "00:10":
                stop = true;
                break;

            case "00:20":
                halfTime = true;
                break;
            case "00:30":
                stop = true;
                break;
            case "00:40":
                stop = true;
                fullTime = true;
                break;

        }
    }


}