How to use SQLite database with an Android application?

AndroidApps/ApplicationsMobile Development

This example demonstrates how do I use the SQLite database with an android application.

Step 1 − Create a new project in Android Studio, go to File ⇒ New Project and fill all required details to create a new project.

Step 2 − Add the following code to res/layout/activity_main.xml.

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:padding="8dp"
   tools:context=".MainActivity">
   <ListView
      android:id="@+id/listView"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:dividerHeight="1dp"
      android:padding="10dp" >
   </ListView>
   <TextView
      android:id="@+id/textView"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_centerInParent="true"
      android:text="" />
</RelativeLayout>

Step 3 − Create a new Java class (DataBaseManager) and add the following code −

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
public class DataBaseManager {
private DatabaseHelper databaseHelper;
private Context context;
private SQLiteDatabase database;
DataBaseManager(Context c) {
   context = c;
   }
   DataBaseManager open() throws SQLException {
      databaseHelper = new DatabaseHelper(context);
      database = databaseHelper.getWritableDatabase();
      return this;
   }
   public void close() {
      databaseHelper.close();
   }
   void insert(String name, String desc) {
      ContentValues contentValue = new ContentValues();
      contentValue.put(DatabaseHelper.SUBJECT, name);
      contentValue.put(DatabaseHelper.DESCRIPTION, desc);
      database.insert(DatabaseHelper.TABLE_NAME, null, contentValue);
   }
   Cursor fetch() {
      String[] columns = new String[] { DatabaseHelper._ID, DatabaseHelper.SUBJECT, DatabaseHelper.DESCRIPTION };
      Cursor cursor = database.query(DatabaseHelper.TABLE_NAME, columns, null, null, null, null, null);
   if (cursor != null) {
      cursor.moveToFirst();
   }
   return cursor;
}
public int update(long _id, String name, String desc) {
   ContentValues contentValues = new ContentValues();
   contentValues.put(DatabaseHelper.SUBJECT, name);
   contentValues.put(DatabaseHelper.DESCRIPTION, desc);
   return database.update(DatabaseHelper.TABLE_NAME, contentValues, DatabaseHelper._ID + " = " + _id, null);
}
public void delete(long _id) {
   database.delete(DatabaseHelper.TABLE_NAME, DatabaseHelper._ID + "=" + _id, null);
}

Step 4 − Create a new Java class (DataBaseHelper) and add the following code

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
class DatabaseHelper extends SQLiteOpenHelper {
   static final String TABLE_NAME = "FOOTBALLPLAYERS";
   static final String _ID = "_id";
   static final String SUBJECT = "subject";
   static final String DESCRIPTION = "description";
   private static final String DB_NAME = "PLAYER_COUNTRIES.DB";
   private static final int DB_VERSION = 1;
   private static final String CREATE_TABLE = "create table " + TABLE_NAME + "("
      + _ID + " INTEGER PRIMARY KEY AUTOINCREMENT, "
      + SUBJECT + " TEXT NOT NULL, " + DESCRIPTION + " TEXT);";
   DatabaseHelper(Context context) {
      super(context, DB_NAME, null, DB_VERSION);
   }
   @Override
   public void onCreate(SQLiteDatabase db) {
      db.execSQL(CREATE_TABLE);
   }
   @Override
   public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
      db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
      onCreate(db);
   }
}

Step 5 − Add the following code to src/MainActivity.java

import android.content.Intent;
import android.database.Cursor;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
import android.widget.TextView;
import androidx.appcompat.app.AppCompatActivity;
public class MainActivity extends AppCompatActivity {
   DataBaseManager dataBaseManager;
   ListView listView;
   SimpleCursorAdapter adapter;
   final String[] from = new String[]{DatabaseHelper._ID, DatabaseHelper.SUBJECT, DatabaseHelper.DESCRIPTION};
   final int[] to = new int[]{R.id.id, R.id.title, R.id.desc};
   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
      dataBaseManager = new DataBaseManager(this);
      dataBaseManager.open();
      Cursor cursor = dataBaseManager.fetch();
      listView = findViewById(R.id.listView);
      listView.setEmptyView(findViewById(R.id.textView));
      adapter = new SimpleCursorAdapter(this, R.layout.activity_view_record, cursor, from, to, 0);
      adapter.notifyDataSetChanged();
      listView.setAdapter(adapter);
      listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
         @Override
         public void onItemClick(AdapterView<?> parent, View view, int position, long viewId) {
            TextView idTextView = view.findViewById(R.id.id);
            TextView titleTextView = view.findViewById(R.id.title);
            TextView descTextView = view.findViewById(R.id.desc);
            String id = idTextView.getText().toString();
            String title = titleTextView.getText().toString();
            String desc = descTextView.getText().toString();
            Intent modifyIntent = new Intent(getApplicationContext(), ModifyPlayerActivity.class);
            modifyIntent.putExtra("title", title);
            modifyIntent.putExtra("desc", desc);
            modifyIntent.putExtra("id", id);
            startActivity(modifyIntent);
         }
      });
   }
   @Override
   public boolean onCreateOptionsMenu(Menu menu) {
      getMenuInflater().inflate(R.menu.main, menu);
      return true;
   }
   @Override
   public boolean onOptionsItemSelected(MenuItem item) {
      int id = item.getItemId();
      if (id == R.id.addRecord) {
         Intent addPlayer = new Intent(this, AddPlayerActivity.class);
         startActivity(addPlayer);
      }
      return super.onOptionsItemSelected(item);
   }
}

Step 6 − Create Two Activities (AddPlayerActivity & ModifyPlayerActivity) and add the following code −

AddPlayerActivity.java −

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import androidx.appcompat.app.AppCompatActivity;
public class AddPlayerActivity extends AppCompatActivity implements
View.OnClickListener {
   Button btnAdd;
   private EditText editSubject;
   private EditText editDescription;
   private DataBaseManager dataBaseManager;
   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setTitle("Add Record");
      setContentView(R.layout.activity_addplayer);
      editSubject = findViewById(R.id.editTextSubject);
      editDescription = findViewById(R.id.editTextDescription);
      btnAdd = findViewById(R.id.add_record);
      dataBaseManager = new DataBaseManager(this);
      dataBaseManager.open();
      btnAdd.setOnClickListener(this);
   }
   @Override
   public void onClick(View v) {
      if (v.getId() == R.id.add_record) {
         final String name = editSubject.getText().toString();
         final String desc = editDescription.getText().toString();
         dataBaseManager.insert(name, desc);
         Intent main = new Intent(AddPlayerActivity.this,
         MainActivity.class).setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
         startActivity(main);
      }
   }
}

activity_addplayer.xml −

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
   android:orientation="vertical" android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:padding="4dp">
   <EditText
      android:id="@+id/editTextSubject"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:ems="10"
      android:hint="Enter Name" >
      <requestFocus />
   </EditText>
   <EditText
      android:id="@+id/editTextDescription"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:hint="Enter Country"
      android:inputType="textMultiLine">
   </EditText>
   <Button
      android:id="@+id/add_record"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_gravity="center"
      android:text="Add Record" />
</LinearLayout>

ModifyPlayerActivity − 

import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
public class ModifyPlayerActivity extends AppCompatActivity implements
View.OnClickListener {
   EditText editTextSub;
   Button updateBtn, deleteBtn;
   EditText editTextDesc;
   private long _id;
   DataBaseManager dataBaseManager;
   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setTitle("Modify Record");
      setContentView(R.layout.activity_modify_player);
      dataBaseManager = new DataBaseManager(this);
      dataBaseManager.open();
      editTextSub = findViewById(R.id.editTextSub);
      editTextDesc = findViewById(R.id.editTextDesc);
      updateBtn = findViewById(R.id.btnUpdate);
      deleteBtn = findViewById(R.id.btnDelete);
      Intent intent = getIntent();
      String id = intent.getStringExtra("id");
      String name = intent.getStringExtra("title");
      String desc = intent.getStringExtra("desc");
      _id = Long.parseLong(id);
      editTextSub.setText(name);
      editTextDesc.setText(desc);
      updateBtn.setOnClickListener(this);
      deleteBtn.setOnClickListener(this);
   }
   @Override
   public void onClick(View v) {
      switch (v.getId()) {
         case R.id.btnUpdate:
         String title = editTextSub.getText().toString();
         String desc = editTextDesc.getText().toString();
         dataBaseManager.update(_id, title, desc);
         this.returnHome();
         break;
         case R.id.btnDelete:
         dataBaseManager.delete(_id);
         this.returnHome();
         break;
      }
   }
   public void returnHome() {
      Intent home_intent = new Intent(getApplicationContext(),
      MainActivity.class).setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
      startActivity(home_intent);
   }
}

activity_modify_player.xml −  

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:orientation="vertical"
   android:padding="10dp" >
   <EditText
      android:id="@+id/editTextSub"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:layout_marginBottom="10dp"
      android:ems="10"
      android:hint="Enter Name" />
   <EditText
      android:id="@+id/editTextDesc"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:hint="Enter Country">
   </EditText>
   <LinearLayout
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:weightSum="2"
      android:gravity="center_horizontal"
      android:orientation="horizontal">
   <Button
      android:id="@+id/btnUpdate"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_weight="1"
      android:text="Update" />
   <Button
      android:id="@+id/btnDelete"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:layout_weight="1"
      android:text="Delete" />
   </LinearLayout>
</LinearLayout>

Step 7 − Create a layout resource file (action_view_record.xml) and add the following code −  

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
   android:orientation="vertical" android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:padding="4dp">
   <TextView
      android:id="@+id/id"
      android:layout_width="25dp"
      android:layout_height="wrap_content"
      android:layout_alignParentStart="true"
      android:layout_alignParentTop="true"
      android:layout_marginEnd="6dp"
      android:padding="3dp"
      android:visibility="visible" />
   <TextView
      android:id="@+id/title"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:layout_marginStart="10dp"
      android:layout_toEndOf="@id/id"
      android:maxLines="1"
      android:padding="3dp"
      android:textSize="17sp"
      android:textStyle="bold" />
   <TextView
      android:id="@+id/desc"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:layout_below="@id/title"
      android:layout_marginStart="10dp"
      android:layout_toEndOf="@id/id"
      android:ellipsize="end"
      android:maxLines="2"
      android:padding="3dp"
      android:visibility="visible" />
</RelativeLayout>

Step 8 − Add the following code to androidManifest.xml 

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
   package="app.com.sample">
   <application
      android:allowBackup="true"
      android:icon="@mipmap/ic_launcher"
      android:label="@string/app_name"
      android:roundIcon="@mipmap/ic_launcher_round"
      android:supportsRtl="true"
      android:theme="@style/AppTheme">
      <activity android:name=".ModifyPlayerActivity"></activity>
         <activity android:name=".MainActivity">
            <intent-filter>
               <action android:name="android.intent.action.MAIN" />
               <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
         </activity>
      <activity android:name=".AddPlayerActivity" />
   </application>
</manifest>

Let's try to run your application. I assume you have connected your actual Android Mobile device with your computer. To run the app from the android studio, open one of your project's activity files and click Run  icon from the toolbar. Select your mobile device as an option and then check your mobile device which will display your default screen −

  

 

Click here to download the project code.

raja
Published on 22-Nov-2019 13:13:32
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