Android Sqlite Database : Update & Delete Data in Android using java

 Delete Data into Database

Database.Java

package com.example.myapplication06.Database;

import android.annotation.SuppressLint;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
import android.widget.Toast;

import androidx.annotation.Nullable;

import com.example.myapplication06.Model.ModelData;

import java.util.ArrayList;
import java.util.List;

public class DBHelper extends SQLiteOpenHelper {

    public static String DBNAME = "Student.db";
    Context activity;

    public DBHelper(@Nullable Context context) {
        super(context, DBNAME, null, 1);
        activity = context;
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        String query = "CREATE TABLE std (id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT, mobile TEXT, email TEXT)";
        db.execSQL(query);
    }

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

    }

    public void deletedata(String id)
    {
        SQLiteDatabase db=getWritableDatabase();
        db.delete("std","id=?",new String[]{id});
    }

    public void updateData(String id,String name,String mobile,String email)
    {
        SQLiteDatabase db=getWritableDatabase();
        ContentValues contentValues=new ContentValues();
        contentValues.put("name",name);
        contentValues.put("mobile",mobile);
        contentValues.put("email",email);


        db.update("std",contentValues,"id=?",new String[]{id});
    }

}

Adapter.Java

package com.example.myapplication06.Adapter;

import android.annotation.SuppressLint;
import android.app.Activity;
import android.app.Dialog;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.TextView;

import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;

import com.example.myapplication06.Database.DBHelper;
import com.example.myapplication06.MainActivity;
import com.example.myapplication06.Model.ModelData;
import com.example.myapplication06.R;

import java.util.ArrayList;
import java.util.List;

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.Viewdata> {

    Activity activity;
    List<ModelData> list = new ArrayList<>();
    private DBHelper dbHelper;

    public MyAdapter(MainActivity mainActivity, List<ModelData> modelDatalist) {
        activity = mainActivity;
        list = modelDatalist;
    }

    @NonNull
    @Override
    public Viewdata onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(activity).inflate(R.layout.item, parent, false);
        return new Viewdata(view);
    }

    @Override
    public void onBindViewHolder(@NonNull Viewdata holder, @SuppressLint("RecyclerView") int position) {
        holder.u_id.setText(list.get(position).getId());
        holder.u_name.setText(list.get(position).getName());
        holder.u_mobile.setText(list.get(position).getMobile());
        dbHelper = new DBHelper(activity);

        holder.delete_img.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                dbHelper.deletedata(list.get(position).getId());
                ((MainActivity) activity).rvlist();

            }
        });

        holder.update_img.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                UpdateDialoge(list.get(position).getId(),list.get(position).getName(),list.get(position).getMobile(),list.get(position).getEmail());
            }
        });
    }

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

    class Viewdata extends RecyclerView.ViewHolder {
        TextView u_id, u_name, u_mobile;
        ImageView delete_img, update_img;

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

            u_id = itemView.findViewById(R.id.u_id);
            u_name = itemView.findViewById(R.id.u_name);
            u_mobile = itemView.findViewById(R.id.u_mobile);
            delete_img = itemView.findViewById(R.id.delete_img);
            update_img = itemView.findViewById(R.id.update_img);

        }
    }


    void UpdateDialoge(String id1,String name1,String mobile1,String email1) {
        Dialog dialog = new Dialog(activity);
        dialog.setContentView(R.layout.dialoge_item);
        Button update_data_btn = dialog.findViewById(R.id.update_data_btn);
        TextView id_txt = dialog.findViewById(R.id.id_txt);
        EditText name_edt = dialog.findViewById(R.id.name_edt);
        EditText edt_mobile = dialog.findViewById(R.id.edt_mobile);
        EditText email_edt = dialog.findViewById(R.id.email_edt);

        id_txt.setText(id1);
        name_edt.setText(name1);
        edt_mobile.setText(mobile1);
        email_edt.setText(email1);

        update_data_btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String id = id_txt.getText().toString();
                String name = name_edt.getText().toString();
                String email = email_edt.getText().toString();
                String mobile = edt_mobile.getText().toString();

                dbHelper.updateData(id, name, mobile, email);
                ((MainActivity) activity).rvlist();
                dialog.dismiss();
            }
        });
        dialog.show();

    }
}

#Android Sqlite Database