package com.example.textjumble;

import android.app.AlertDialog;
import android.os.Bundle;

import android.content.DialogInterface;

import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

import androidx.appcompat.app.AppCompatActivity;

import java.util.ArrayList;
import java.util.List;


public class MainActivity extends AppCompatActivity implements OnClickListener
{
    private Button exitButton;
    private EditText nameEntry;
    private String name;
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        exitButton = (Button)findViewById(R.id.exitButton);
        nameEntry = (EditText)findViewById(R.id.nameEntry);
        nameEntry.setWidth(120);
        exitButton.setOnClickListener(this);
        nameEntry.setFocusable(true);
    }// End of onCreate
    @Override
    public void onClick(View v)
    {
        // Check for exit button. Pop up dialogue if found
        if (v == exitButton)
        {
            name = nameEntry.getText().toString();
            showtbDialog(name);
        }
    }// End of onClick
    private void showtbDialog(String s)
    {
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        char [] array = s.toCharArray();
        int len = s.length();
        for (int i = 0; i < 10; i++)
        {
            int max = array.length;
            int min = 1;
            int a = (int)(Math.random() * ((max - min) + 1)) + min;
            int b = (int)(Math.random() * ((max - min) + 1)) + min;
            a--;
            b--;
            char temp = array[a];
            array[a] = array[b];
            array[b] = temp;
        }


        String newS = new String (array);

        builder.setMessage(newS);
        builder.setCancelable(true);


        AlertDialog alert = builder.create();
        alert.show();
    }
}// End of Activity class





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<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Welcome to Mobile Device Programming"
        />
    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        >
        <TextView
            android:id="@+id/nameLabel"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Enter string to jumble "
            />
        <EditText
            android:id="@+id/nameEntry"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:inputType="text"
            android:text=""
            />
        <requestFocus />
    </LinearLayout>
    <Button
        android:id="@+id/exitButton"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Press to Jumble"
        />


</LinearLayout>