Question

如何随机化字符串？ 我有 3个字符串和 1 TextView 。对于TextViev，我想＆＃34;写＆＃34;字符串，当单击按钮时。我的代码是：

主要xml：

<Button
    android:id="@+id/btn1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginBottom="100dp"
    android:text="Push Me"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toBottomOf="@+id/textView1"
    tools:ignore="UnknownId" />

<TextView
    android:id="@+id/tv1"
    android:text="VALAMI"
    android:layout_width="0dp"
    android:layout_height="182dp"
    android:layout_marginBottom="18dp"
    android:layout_marginEnd="6dp"
    android:layout_marginStart="6dp"
    android:layout_marginTop="163dp"
    app:layout_constraintBottom_toTopOf="@+id/button1"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toTopOf="parent"
    tools:ignore="UnknownId" />

MainActivity.java

Button btn1;
TextView tv1;

String a = "s1";
String b = "s2";
String c = "s3";

Answer 1

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.main);

    ArrayList<String> strings = {"s1", "s2", "s3"};


    Button button = findViewById(R.id.btn1);
    TextView text = findViewById(R.id.tv1);

    button.setOnClickListener(new View.OnClickListener(){

       public void onClick(View v){

       Random randomno = new Random();
       text.setText(strings.get(randomno.nextInt(3));


       } 

    });
}

如何随机化字符串？

1 个答案: