lab3

<?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">

    <TextView
        android:id="@+id/genText"
        android:layout_width="246dp"
        android:layout_height="148dp"
        android:text="@string/defaultMes"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintHorizontal_bias="0.503"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintVertical_bias="0.302" />

    <Button
        android:id="@+id/genButton"
        android:layout_width="96dp"
        android:layout_height="97dp"
        android:layout_marginBottom="96dp"
        android:background="@drawable/shaperound"
        android:text="@string/genKey"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent" />

    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/transtxt"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.502"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/genButton"
        app:layout_constraintVertical_bias="0.751" />

</androidx.constraintlayout.widget.ConstraintLayout>
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package com.example.lab3t;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

import java.util.Random;


public class MainActivity extends AppCompatActivity {
    Button genBut;
    TextView genTxt;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        final Random rand = new Random();

        genBut = (Button)findViewById(R.id.genButton);
        genTxt = (TextView)findViewById(R.id.genText);
        final String[] jokTab = new String [4];

        jokTab[0] = getString(R.string.dry1);
        jokTab[1] = getString(R.string.dry2);
        jokTab[2] = getString(R.string.dry3);
        jokTab[3] = getString(R.string.dry4);


        genBut.setOnClickListener(
                new View.OnClickListener(){
                    @Override
                    public void onClick(View v) {
                        int randomint = rand.nextInt(4);
                        genTxt.setText(jokTab[randomint]);
                    }
                });
    }
}