按钮无法立即正常工作

Question

我正在编写带有片段的标签栏程序。我有4个片段，一个标签栏正在处理它们。我的问题是我无法使用片段生命周期方法（或者我无法学习）。我有一个运行一些代码的按钮，我想计算从输入时间到现在已经过去了多少时间。该程序会计算时间，但不会覆盖textview，我更改了片段并返回了相关片段，它已经起作用了，但我想像您所知道的那样突然起作用:)。我希望我能向您解释，因为我不会说自己具备良好的英语水平。谢谢！

public class fragmentTimer extends Fragment {
@Nullable
TextView textView;
EditText dateText;
Button buttonTime;
long b;
SharedPreferences preferences;
int beforeAfter;
boolean isPast;


@Override
public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);
    //buttonTime = (Button) view.findViewById(R.id.button);
}

public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragmenttimer, container, false);


    return view;
}

@Override
public void onActivityCreated(@Nullable Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);
    final TextView textView = (TextView) getView().findViewById(R.id.textView4);
    dateText = getView().findViewById(R.id.dateText);

    buttonTime = (Button) getView().findViewById(R.id.button);
    buttonTime.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Date userDate = new Date();
            Date currDate = new Date();
            System.out.printf("%1$s %2$tB %2$td, %2$tY", "Due date:", currDate);
            String str = String.format("Current Date/Time : %tc", currDate);
            //textView.setText(str);
            String dateString;
            String fromDate = "01/07/2019";
            dateString = dateText.getText().toString();
            String fromDate2 = dateString;
            DateFormat df = new SimpleDateFormat("dd/MM/yyyy");
            Date dtt = null;
            try {
                dtt = df.parse(fromDate2);
            } catch (ParseException e) {
                e.printStackTrace();
            }
            java.sql.Date ds = new java.sql.Date(dtt.getTime());
            beforeAfter = currDate.compareTo(dtt);
            if(beforeAfter > 0){
                b = currDate.getTime() - dtt.getTime();
                isPast = true;

            }else if(beforeAfter < 0){
                b = dtt.getTime() - currDate.getTime();
                isPast = false;
            }
        }
    });

    int saniye,dakika,saat,gun;
    b= b/1000;
    saniye = (int) (b % 60);
    b = b / 60;
    dakika = (int) (b % 60);
    b = b / 60;
    saat = (int) (b % 24);
    b= b / 24;
    gun = (int) b;
    String durum = "";
    if(isPast == true){
        durum = "Geçti";
    }
    else if(isPast == false){
        durum = "Kaldı";
    }
    //textView.setText("saniye :" + saniye + " dakika :" + dakika + "\n saat :" + saat + "gün :" + gun);

        textView.setText(+gun + " Gün " + saat + " Saat " + dakika + " Dakika " + saniye + " Saniye " + durum + " ");
}

public void buttonTime9(View view) {
    Date userDate = new Date();
    Date currDate = new Date();
    System.out.printf("%1$s %2$tB %2$td, %2$tY", "Due date:", currDate);
    String str = String.format("Current Date/Time : %tc", currDate);
    textView.setText(str);
    String dateString;
    String fromDate = "19/05/2009";
    dateString = dateText.getText().toString();
    String fromDate2 = dateString;
    DateFormat df = new SimpleDateFormat("dd/MM/yyyy");
    Date dtt = null;
    try {
        dtt = df.parse(fromDate);
    } catch (ParseException e) {
        e.printStackTrace();
    }
    java.sql.Date ds = new java.sql.Date(dtt.getTime());
    long b = currDate.getTime() - dtt.getTime();
    textView.setText("Fark" + b);
    System.out.println("fark " +  b);
        }

   }