如何结束定时器并让应用程序在定时器结束后执行命令？

Question

定时器结束后继续负数计数，不执行Toast命令！！ Java文件👇

package com.example.myapplication;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;
import android.widget.Toast;

import java.util.Timer;
import java.util.TimerTask;

public class MainActivity2 extends AppCompatActivity {
private Timer quTime;
private int totalMinute=1;
private  int second =0;
Intent intent;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);
        final String Selecttopic=getIntent().getStringExtra("S topic");
        TextView texr =findViewById(R.id.ttt);
texr.setText(Selecttopic);
TextView rr=findViewById(R.id.te);

settime(texr);

    }

    private void settime (TextView timerTextView){

        quTime = new Timer();
        quTime.scheduleAtFixedRate(new TimerTask() {
            @Override
            public void run() {
                if(second==0){totalMinute--;second=59;
            } else if (second==0&&totalMinute==0) {
quTime.purge();
quTime.cancel();
                    Toast.makeText(MainActivity2.this,"timeover",Toast.LENGTH_SHORT).show();

                }else {second--;}
                runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        String finalMinute = String.valueOf(totalMinute);
                        String finalSecond = String.valueOf(second);
if(finalMinute.length()==1){finalMinute="0"+finalMinute;
                    }if(finalSecond.length()==1){finalSecond="0"+finalSecond;}
timerTextView.setText(finalMinute+":"+finalSecond);


                    }
                });
            }
        },1000, 1000);
    }


}

XML文件👇

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity2">

    <TextView
        android:id="@+id/ttt"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="TextView"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/te"

        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:layout_marginBottom="10dp"

        android:text="0"
        app:layout_constraintBottom_toTopOf="@+id/ttt"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>

我尝试更改这部分代码（（例如））

 else if (second==0&&totalMinute==0) {
                        quTime.purge();
                        quTime.cancel();
                        Toast.makeText(MainActivity.this,"timeover",Toast.LENGTH_SHORT).show();

到

 else if (second==57&&totalMinute==0) {
                        quTime.purge();
                        quTime.cancel();
                        Toast.makeText(MainActivity.this,"timeover",Toast.LENGTH_SHORT).show();

这导致应用程序在到达第 57 秒时停止并退出，而不是执行 Toast 为什么？？！！

所以当它...等于零时，计数器继续负数计数并且不会停止，但是如果你将它设为任何其他数字，应用程序将停止，并且在这两种情况下都不会执行 Toast 我想让定时器停止并执行 Toast 命令，请帮忙