ASデータベース編①解説～入力したテキストをSQLiteデータベースに登録し、一覧を表示する～

MainActivity.java

package com.example.databasedisease;

import androidx.appcompat.app.AppCompatActivity;

import android.content.ContentValues;
import android.content.Intent;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class MainActivity extends AppCompatActivity {

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

        EditText disease_text = findViewById(R.id.disease_text);
        EditText classification_text = findViewById(R.id.classification_text);
        EditText concept_text = findViewById(R.id.concept_text);
        EditText sign_text = findViewById(R.id.sign_text);
        EditText diagnosis_text = findViewById(R.id.diagnosis_text);
        EditText therapy_text = findViewById(R.id.therapy_text);

        //データベースに関する記述

        MyOpenHelper helper = new MyOpenHelper(this);
        SQLiteDatabase db = helper.getWritableDatabase();

        //入力したデータの処理
        Button register_btn = findViewById(R.id.register_btn);
        register_btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String disease = disease_text.getText().toString();
                String classification = classification_text.getText().toString();
                String concept = concept_text.getText().toString();
                String sign = sign_text.getText().toString();
                String diagnosis = diagnosis_text.getText().toString();
                String therapy = therapy_text.getText().toString();

                ContentValues contentvalues = new ContentValues();
                contentvalues.put("disease",disease);
                contentvalues.put("classification",classification);
                contentvalues.put("concept",concept);
                contentvalues.put("sign",sign);
                contentvalues.put("diagnosis",diagnosis);
                contentvalues.put("therapy",therapy);


                long id =db.insert("disease_data",disease,contentvalues);
            }
        });

        Button clear_btn = findViewById(R.id.clear_btn);
        clear_btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                disease_text.setText("");
                classification_text.setText("");
                concept_text.setText("");
                sign_text.setText("");
                diagnosis_text.setText("");
                therapy_text.setText("");
            }
        });



        Button configure_btn = findViewById(R.id.configure_btn);
        configure_btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent = new Intent(MainActivity.this,SecondActivity.class);
                startActivity(intent);
            }
        });
    }
}

activity_main.xml

<?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:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity"
    android:orientation="vertical">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="疾患名："/>

    <EditText
        android:id="@+id/disease_text"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="分類："/>

    <EditText
        android:id="@+id/classification_text"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="概念："/>

    <EditText
        android:id="@+id/concept_text"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="症状："/>

    <EditText
        android:id="@+id/sign_text"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="診断："/>

    <EditText
        android:id="@+id/diagnosis_text"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="治療："/>

    <EditText
        android:id="@+id/therapy_text"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>

    <Button
        android:id="@+id/register_btn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="登録" />

    <Button
        android:id="@+id/clear_btn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="クリア"
        android:layout_marginTop="10dp"/>

    <Button
        android:id="@+id/configure_btn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="一覧表示"
        android:layout_marginTop="10dp"/>

</LinearLayout>

SecondActivity.java

package com.example.databasedisease;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.graphics.Color;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.TextView;

public class SecondActivity extends AppCompatActivity {

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

        LinearLayout layout = new LinearLayout(this);
        layout.setOrientation(LinearLayout.VERTICAL);
        setContentView(layout);

        MyOpenHelper helper = new MyOpenHelper(this);
        SQLiteDatabase db = helper.getReadableDatabase();

        Cursor c = db.query("disease_data",new String[]{"disease","classification","concept","sign","diagnosis","therapy"},null,null,null,null,null);

        boolean mov = c.moveToFirst();
        while(mov){
            TextView textView1 = new TextView(this);
            TextView textView2 = new TextView(this);
            TextView textView3 = new TextView(this);
            TextView textView4 = new TextView(this);
            TextView textView5 = new TextView(this);
            TextView textView6 = new TextView(this);

            textView1.setText("疾患名:"+c.getString(0));
            textView1.setTextSize(25);
            textView1.setTextColor(Color.parseColor("#FF66FF"));
            textView2.setText("分類:"+c.getString(1));
            textView2.setTextSize(20);
            textView3.setText("概念："+c.getString(2));
            textView3.setTextSize(20);
            textView4.setText("症状："+c.getString(3));
            textView4.setTextSize(20);
            textView5.setText("診断："+c.getString(4));
            textView5.setTextSize(20);
            textView6.setText("治療："+c.getString(5));
            textView6.setTextSize(20);
            mov = c.moveToNext();
            layout.addView(textView1);
            layout.addView(textView2);
            layout.addView(textView3);
            layout.addView(textView4);
            layout.addView(textView5);
            layout.addView(textView6);

        }
        c.close();
        db.close();

        Button back_btn = new Button(this);
        back_btn.setText("Back");
        layout.addView(back_btn);

        back_btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                startActivity(new Intent(SecondActivity.this,MainActivity.class));
            }
        });
    }
}

activity_second.xml

<?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:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".SecondActivity">

</LinearLayout>

MyOpenHelper.java（SQLiteOpenHelperを継承したクラス）

package com.example.databasedisease;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

public class MyOpenHelper extends SQLiteOpenHelper {
    public MyOpenHelper(Context context) {
        super(context, "disease_db", null, 1);
    }

    @Override
    public void onCreate(SQLiteDatabase sqLiteDatabase) {
        /*
        create table disease_data(
           id int auto_increment primary key not null,
           name varchar(25) not null,
           age int not null)
         */

        sqLiteDatabase.execSQL("create table disease_data("
                                +"disease text not null primary key,"
                                +"classification text not null,"
                                +"concept text not null,"
                                +"sign text not null,"
                                +"diagnosis text not null,"
                                +"therapy text not null"
                                +")");
    }

    @Override
    public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {

    }
}

次回は、データ削除ボタンや　データ検索ボタンを追加する予定です。