SQL android

 1. SQL table Database create 

package abhiandroid.com.Sql;

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

import androidx.annotation.Nullable;

public class MyDb extends SQLiteOpenHelper {

    public static final String Table= "ex";
    public static  final int version = 1;


    public MyDb(@Nullable Context context) {
        super(context, Table, null, version);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {

        db.execSQL("CREATE TABLE " + Table + "("
                        +  "id INTEGER PRIMARY KEY," +
                " name TEXT NOT NULL," + "  gender NOT NULL"  +")");

    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

        db.execSQL( "DROP TABLE IF EXISTS " + Table);

        onCreate(db);

    }
    
    
}

2.SQLliteOpenHelper.class

package abhiandroid.com.Sqlite;

import static android.os.Build.ID;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;

import java.util.ArrayList;

public class MyDb extends SQLiteOpenHelper {

    public static final String Table= "ex";
    public static  final int version = 1;


    public MyDb(@Nullable Context context) {
        super(context, Table, null, version);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {

        db.execSQL("CREATE TABLE " + Table + "("
                        +  "ID INTEGER PRIMARY KEY," +
                " NAME TEXT NOT NULL," + "  GENDER NOT NULL"  +")");

    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

        db.execSQL( "DROP TABLE IF EXISTS " + Table);

        onCreate(db);

    }
    public void insert (int id , String name , String gender){
        SQLiteDatabase db = getWritableDatabase();

        ContentValues values = new ContentValues();


        values.put("ID",id);
        values.put("NAME",name);
        values.put("GENDER",gender);

        db.insert(Table,null,values);

        db.close();


    }
    public ArrayList<Model>farr(){

        SQLiteDatabase db = this.getReadableDatabase();

      Cursor cursor = db.rawQuery("SELECT * FROM " + Table,null);

      ArrayList<Model> arrf = new ArrayList<>();

      while (cursor.moveToNext()) {

          Model model = new Model();
          model.id = String.valueOf(cursor.getInt(0));
          model.name = cursor.getString(1);
          model.gender = cursor.getString(2);

          arrf.add(model);




      }
      return arrf;

    }
    public void update(String id, String name ){
     SQLiteDatabase db = this.getWritableDatabase();

     ContentValues values = new ContentValues();
     values.put("name",name);

     db.update(Table,values,"ID = ?",new String[]{String.valueOf(id)});


     db.close();

    }
    public  void  Delete(String id){
        SQLiteDatabase db = this.getWritableDatabase();

        db.delete(Table,"ID = ?", new String[]{id});
        db.close();
    }


}

3. MainActivity 

package abhiandroid.com.recyclerjava;


import androidx.appcompat.app.AppCompatActivity;

import android.annotation.SuppressLint;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

import java.util.ArrayList;


public class MainActivity extends AppCompatActivity {

    EditText idEdt , nameEdt, genderEdt;
    Button button, button2;

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

        idEdt = findViewById(R.id.id);
        nameEdt = findViewById(R.id.name);
        genderEdt = findViewById(R.id.gender);
        button = findViewById(R.id.button);
        button2 = findViewById(R.id.button2);

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {


                int id = Integer.parseInt(idEdt.getText().toString());

                String name = nameEdt.getText().toString();

                String gender = genderEdt.getText().toString();


                MyDb myDb = new MyDb(MainActivity.this);

                if ( name.isEmpty() && gender.isEmpty()){

                    Toast.makeText(MainActivity.this, "not", Toast.LENGTH_SHORT).show();

                    return;
                }


                myDb.insert(id,name,gender);

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

                idEdt.setText("");

                nameEdt.setText("");

                genderEdt.setText("");


            }
        });

        button2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent  intent = new Intent(MainActivity.this,MainActivity2.class);

                startActivity(intent);
            }
        });




        MyDb myDb = new MyDb(MainActivity.this);

       ArrayList<Model> farr = myDb.farr();

       for (int i = 0; i<farr.size();i++)



        Log.d("App","name : "+ farr.get(i).name + ", gender :" + farr.get(i).gender );

    }

}

.4.

package abhiandroid.com.recyclerjava;

public class Model {

    String id, name, gender;

}

5. detrend method

package abhiandroid.com.recyclerjava;

import androidx.appcompat.app.AppCompatActivity;

import androidx.recyclerview.widget.LinearLayoutManager;

import androidx.recyclerview.widget.RecyclerView;

import android.os.Bundle;

import android.widget.Toast;

import java.util.ArrayList;

public class MainActivity2 extends AppCompatActivity {

    RecyclerView rcy;

    ArrayList<Rmodle> arr = new ArrayList<>();

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main2);

        MyDb myDb = new MyDb(MainActivity2.this);

        ArrayList<Model> farr = myDb.farr();

        rcy = findViewById(R.id.rcy);

        rcy.setLayoutManager(new LinearLayoutManager(this));

        

        for (int i = 0; i< farr.size();i++) {

         String id = farr.get(i).id;

         String name = farr.get(i).name;

         String gender = farr.get(i).gender;

            Toast.makeText(this, "h"+ name, Toast.LENGTH_SHORT).show();

            Rmodle rmodle = new Rmodle(id,name,gender);

            arr.add(rmodle);

        }

        Adapter adapter = new Adapter(this,arr);

        rcy.setAdapter(adapter);

    }

}

6.

package abhiandroid.com.recyclerjava;

import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;

import android.os.Bundle;
import android.widget.Toast;

import java.util.ArrayList;

public class MainActivity2 extends AppCompatActivity {

    RecyclerView rcy;

    ArrayList<Rmodle> arr = new ArrayList<>();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);

        MyDb myDb = new MyDb(MainActivity2.this);

        ArrayList<Model> farr = myDb.farr();


        rcy = findViewById(R.id.rcy);

        rcy.setLayoutManager(new LinearLayoutManager(this));




        Adapter adapter = new Adapter(this,farr);

        rcy.setAdapter(adapter);


       //  re();

     //



    }

    // refresh method
    public void re( ) {

        MyDb myDb = new MyDb(MainActivity2.this);
        ArrayList<Model> farr = myDb.farr();
        Adapter adapter = new Adapter(this,farr);

        adapter.notifyDataSetChanged();
    }

}

7.

package abhiandroid.com.recyclerjava;

import android.annotation.SuppressLint;
import android.content.Context;
import android.content.Intent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.TextView;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.RecyclerView;

import java.util.ArrayList;

public class Adapter extends RecyclerView.Adapter<Adapter.MyHolder> {

    Context context;
   // ArrayList <Rmodle>arr;

   ArrayList<Model>farr;

    public Adapter(Context context, ArrayList<Model> farr) {
        this.context = context;
        this.farr = farr;
    }

    @NonNull
    @Override
    public MyHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {

     View view = LayoutInflater.from(context).inflate(R.layout.item,null,false);

        return new MyHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull MyHolder holder, int position) {

        Model model = farr.get(position);

        holder.textView.setText(model.name);

        String all = "al5";


        holder.button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

               MyDb myDb = new MyDb(context.getApplicationContext());
              myDb.update(model.id.toString(), all);

                holder.textView.setText(all);


             //  myDb.Delete(model.id.toString());
              // MainActivity2 mainActivity2 = new MainActivity2();
              // mainActivity2.re();

               // Adapter adapter = new Adapter(context.getApplicationContext(),farr);

              //  adapter.notifyDataSetChanged();

              //  MainActivity2 mainActivity2 = new MainActivity2();
              // mainActivity2.finish();
              //  Intent refresh = new Intent(context, MainActivity2.class);
               // context.startActivity(refresh);
               // mainActivity2.finish();


             //   arr.remove(position);
                //arr.notifyAll();
           //  notifyDataSetChanged();
              //arr.remove(position);
              // rcy.removeViewAt(position);
            //    notifyItemRemoved(model,position);
               // notifyItemRangeChanged(position, arr.size());

            }
        });
    }

    @Override
    public int getItemCount() {
        return farr.size();
    }

    public class MyHolder extends RecyclerView.ViewHolder {

        TextView textView;
        Button button;


        public MyHolder(@NonNull View itemView) {
            super(itemView);

            textView = itemView.findViewById(R.id.text);

            button = itemView.findViewById(R.id.button);


        }
    }
}

8.

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