파드레의 요모조모

package com.jproject.mysturdy;

import androidx.appcompat.app.AppCompatActivity;

import android.app.LauncherActivity;
import android.graphics.Color;
import android.graphics.drawable.ColorDrawable;
import android.os.Bundle;
import android.util.SparseBooleanArray;
import android.view.View;
import android.widget.Adapter;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.Toast;

import java.lang.reflect.Array;
import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {
    ArrayList<String> Items = new ArrayList<String>();
    ArrayAdapter<String> Adapter;
    ListView list;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Items.add("Frist");
        Items.add("Second");
        Items.add("Third");
        Items.add("Fourth");
        Items.add("Fifth");

        Adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_multiple_choice, Items);

        list = (ListView) findViewById(R.id.list);
        list.setAdapter(Adapter);
        list.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
    }

    public void mOnclick(View v) {
        EditText ed = (EditText)findViewById(R.id.newitem);
        int pos;
        String text;
        SparseBooleanArray sb;

        switch(v.getId()){
            case R.id.add:
                text = ed.getText().toString();
                if (text.length() != 0){
                    Items.add(text);
                    ed.setText("");
                    Adapter.notifyDataSetChanged();
                }
                break;
                case R.id.change:
                    sb = list.getCheckedItemPositions();
                    text = ed.getText().toString();
                    pos = list.getCheckedItemPosition();
                    if (sb.size() != 0){
                        for (int i = list.getCount()-1;i>=0;i--){
                            if(sb.get(i)){
                                Items.remove(i);
                                Items.add(i,text);
                            }
                        }

                        list.clearChoices();
                        ed.setText("");
                        Adapter.notifyDataSetChanged();
                    }
                    break;

            case R.id.delete:

                pos = list.getCheckedItemPosition();
                sb = list.getCheckedItemPositions();

                if (sb.size() != 0){
                    for (int i = list.getCount()-1;i>=0;i--){
                        if(sb.get(i)){
                            Items.remove(i);
                        }
                    }

                    list.clearChoices();
                    Adapter.notifyDataSetChanged();
                }
                break;
        }
    }
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <EditText
        android:id="@+id/newitem"
        android:layout_width="wrap_content"
        android:layout_height="120px"
        />
    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <Button
            android:id="@+id/add"
            android:layout_width="8px"
            android:layout_weight="3"
            android:layout_height="wrap_content"
            android:text="add"
            android:onClick="mOnclick"
            />
        <Button
            android:id="@+id/change"
            android:layout_width="8px"
            android:layout_weight="3"
            android:layout_height="wrap_content"
            android:text="change"
            android:onClick="mOnclick"
        />
        <Button
            android:id="@+id/delete"
            android:layout_width="8px"
            android:layout_weight="3"
            android:layout_height="wrap_content"
            android:text="delete"
            android:onClick="mOnclick"
            />
    </LinearLayout>
    <ListView
        android:id="@+id/list"
        android:layout_width="match_parent"
        android:layout_height="500px"
        />
</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <EditText
        android:id="@+id/newitem"
        android:layout_width="wrap_content"
        android:layout_height="120px"
        />
    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <Button
            android:id="@+id/add"
            android:layout_width="8px"
            android:layout_weight="3"
            android:layout_height="wrap_content"
            android:text="add"
            android:onClick="mOnclick"
            />
        <Button
            android:id="@+id/change"
            android:layout_width="8px"
            android:layout_weight="3"
            android:layout_height="wrap_content"
            android:text="change"
            android:onClick="mOnclick"
        />
        <Button
            android:id="@+id/delete"
            android:layout_width="8px"
            android:layout_weight="3"
            android:layout_height="wrap_content"
            android:text="delete"
            android:onClick="mOnclick"
            />
    </LinearLayout>
    <ListView
        android:id="@+id/list"
        android:layout_width="match_parent"
        android:layout_height="500px"
        />
</LinearLayout>

package com.jproject.mysturdy;

import androidx.appcompat.app.AppCompatActivity;

import android.app.LauncherActivity;
import android.graphics.Color;
import android.graphics.drawable.ColorDrawable;
import android.os.Bundle;
import android.view.View;
import android.widget.Adapter;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.Toast;

import java.lang.reflect.Array;
import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {
    String[] arGeneral = {"김유신","이순신","강감찬","을지문덕"};
    ArrayList<String> Items = new ArrayList<String>();
    ArrayAdapter<String> Adapter;
    ListView list;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Items.add("Frist");
        Items.add("Second");
        Items.add("Third");

        Adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_single_choice, Items);

        list = (ListView) findViewById(R.id.list);
        list.setAdapter(Adapter);
        list.setChoiceMode(ListView.CHOICE_MODE_SINGLE);
    }

    public void mOnclick(View v) {
        EditText ed = (EditText)findViewById(R.id.newitem);
        int pos;
        String text;
        switch(v.getId()){
            case R.id.add:
                text = ed.getText().toString();
                if (text.length() != 0){
                    Items.add(text);
                    ed.setText("");
                    Adapter.notifyDataSetChanged();
                }
                break;
                case R.id.change:
                    text = ed.getText().toString();
                    pos = list.getCheckedItemPosition();
                    if (text.length() != 0|pos != ListView.INVALID_POSITION){
                        Items.remove(pos);
                        Items.add(pos,text);
                        ed.setText("");
                        Adapter.notifyDataSetChanged();
                    }
                    break;

            case R.id.delete:

                pos = list.getCheckedItemPosition();
                if (pos != ListView.INVALID_POSITION){
                    Items.remove(pos);
                    list.clearChoices();
                    Adapter.notifyDataSetChanged();
                }
                break;
        }
    }
}