Android 小工具--随机数获取工具类

1.RandomDateUtil类代码

public class RandomDateUtil { public static int DATA(){//int int min=1; int max=100; Random random = new Random(); return random.nextInt(max)%(max-min+1) + min; } public static String DATA2(){//String int min=1; int max=100; Random random = new Random(); int num = random.nextInt(max)%(max-min+1) + min; return String.valueOf(num); } }

2.布局文件

一个按钮，每次点击获取随机数

<?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=".MainActivity"> <Button android:id="@+id/button" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginTop="100dp" android:text="随机数获取" app:layout_constraintLeft_toLeftOf="parent" app:layout_constraintRight_toRightOf="parent" app:layout_constraintTop_toTopOf="parent" /> </androidx.constraintlayout.widget.ConstraintLayout>

3.java代码

public class MainActivity extends AppCompatActivity { Button mButton; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); mButton=findViewById(R.id.button); mButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { mButton.setText(RandomDateUtil.DATA2()); } }); } }

运行