اصافه و ذحیره شدن به لیست ویو

برنامه نوشته که ورودی را گرفته و  در لیست ویو نشان دهد

و با خارج شدن از برنامه پاک نشود 

کد های جاوا :

import android.content.Context;
import android.content.SharedPreferences;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import org.xml.sax.DTDHandler;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import static com.example.amir.test6.R.id.add;

public class MainActivity extends AppCompatActivity {
    EditText editText;
    Button addButton;
    ListView listView;
    String gettext;
    ArrayList<String> listItems;
    ArrayAdapter<String> adapter;
    String [] str ={"tehran","esfahan","shiraz","sistan","kerman","khorasan"};
    SharedPreferences sharedPreferences;
    public static final String Name = "keyname";

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        editText = (EditText) findViewById(R.id.editText);
        addButton = (Button) findViewById(R.id.additem);
        sharedPreferences =getSharedPreferences("mypref", Context.MODE_PRIVATE);
        listView = (ListView) findViewById(R.id.listview);
        listItems = new ArrayList<String>();

        Set<String> set = sharedPreferences.getStringSet("set",new HashSet<String>());

        for(String s :set)
        {
            System.out.println("first add");
            System.out.println(s);
            listItems.add(s);
        }


        adapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1, listItems);

        listView.setAdapter(adapter);
        addButton.setOnClickListener(new View.OnClickListener() {
            AlertDialog.Builder alert = new AlertDialog.Builder(MainActivity.this);

            public void onClick(View v) {
                gettext = editText.getText().toString();
                if (TextUtils.isEmpty(gettext))
                {// Toast.makeText(MainActivity.this, " please enter your char ", Toast.LENGTH_LONG).show();
                     alert.setMessage("please enter your char");
                    alert.show();
                }
                else
                {
                    listItems.add(editText.getText().toString());
                    adapter.notifyDataSetChanged();

                    SharedPreferences.Editor sEdit = sharedPreferences.edit();
                    Set<String> strings = new HashSet<String>();
                    for (String  s : listItems)
                    {
                        strings.add(s);
                        System.out.println(s);
                    }

                    sEdit.putStringSet("set",strings);
                    sEdit.apply();

                    Toast.makeText(MainActivity.this, "Saved", Toast.LENGTH_SHORT).show();

                    editText.setText(sharedPreferences.getString(Name, null));
                    editText.setText("");
                }



            }
        });
        listView.setOnItemClickListener(new AdapterView.OnItemClickListener()
        {
            @Override
            public void onItemClick(AdapterView<?> a, View v, int position, long id)
            {
                Toast.makeText(MainActivity.this, "Checked", Toast.LENGTH_LONG).show();
            }
        });
    }
}

کد های xml :

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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="com.example.amir.test6.MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello User!"
        android:textSize="30dp"
        android:background="#af1"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintHorizontal_bias="0.802"
        app:layout_constraintVertical_bias="0.054"
        android:id="@+id/textView"
        android:layout_marginEnd="12dp"
        android:layout_alignParentTop="true"
        android:layout_alignParentEnd="true" />

    <ListView
        android:layout_width="150dp"
        android:layout_height="400dp"
        tools:layout_editor_absoluteX="8dp"
        tools:layout_editor_absoluteY="8dp"
        android:id="@+id/listview"
        android:background="#8ad"
        android:layout_below="@+id/additem"
        android:layout_alignParentStart="true" />

    <EditText
        android:id="@+id/editText"
        android:layout_width="155dp"
        android:layout_height="50dp"
        android:ems="10"
        android:inputType="textPersonName"
        android:hint="Please Enter Your Text"
        android:background="#dd5"
        android:layout_alignParentTop="true"
        android:layout_alignParentStart="true" />

    <Button
        android:id="@+id/additem"
        android:layout_width="150dp"
        android:layout_height="50dp"
        android:text="list add"
        android:hint="Please Enter Your Text"
        android:background="#f8f"
        android:onClick="onClick"
        android:layout_below="@+id/editText"
        android:layout_alignParentStart="true" />

</RelativeLayout>