**Hi there i am facing issue in making cart in app i want to remove row from custom list view and record from SQlite Database need help.I just want the particular row delete from the Custom list adapter and delete particular record from database **
This is cartAdapter file
import org.json.JSONArray;
import com.squareup.picasso.Picasso;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
public class cartAdapter extends BaseAdapter{
String [] pIdz;
String [] pNamz;
String [] pPrizs;
// List<String> imges;
Context context;
ShopingCartHelper obj=new ShopingCartHelper(context);
private static LayoutInflater inflater=null;
JSONArray jCat = null;
int count=0;
ProgressDialog pDialog;
public cartAdapter(PlaceOrder cat,
String[] pIds,String[] pNams, String[] pprise) {
pIdz=pIds;
pNamz=pNams;
context=cat;
pPrizs=pprise;
inflater = ( LayoutInflater )context.
getSystemService(Context.LAYOUT_INFLATER_SERVICE);
// TODO Auto-generated constructor stub
}
@Override
public int getCount() {
// TODO Auto-generated method stub
if(pIdz==null){
Toast.makeText(context, "There is issue with net connection.", Toast.LENGTH_LONG).show();
//Intent i=new Intent(context,WelcomeActivity.class);
//context.startActivity(i);
return count ;
}else{
return pIdz.length;
}
}
@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return position;
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
public class holder{
TextView pid;
TextView pname;
TextView pprise;
Button delete;
ListView lv;
}
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
final holder hldr=new holder();
View rowView = null;
Bitmap bitmap = null;
rowView = inflater.inflate(R.layout.place_order_item_list, null);
hldr.pid=(TextView) rowView.findViewById(R.id.item_id);
hldr.pname=(TextView) rowView.findViewById(R.id.item_name);
hldr.pprise=(TextView) rowView.findViewById(R.id.item_price);
hldr.delete=(Button) rowView.findViewById(R.id.delete);
hldr.pid.setText(pIdz[position]);
hldr.pname.setText(pNamz[position]);
hldr.pprise.setText(pPrizs[position]);
//
// Picasso.with(context).load(imgs[position]).into(hldr.img);
hldr.delete.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
// rowView.remove(position); //removing from your List
Toast.makeText(context, "Delete",Toast.LENGTH_LONG).show();
int pid=Integer.parseInt(hldr.pid.getText().toString());
obj.deleteRec(pid);
//hldr.pid.remove(position);
//cartAdapter.this.
}
});
rowView.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// // TODO Auto-generated method stub
// cartAdapter.this.pIdz.remove[position];
Toast.makeText(context, "hi",Toast.LENGTH_LONG).show();
}
});
return rowView;
// TODO Auto-generated method stub
}
}
this is database file
public class ShopingCartHelper extends SQLiteOpenHelper {
public static final String DATABASE_NAME = "cart.db";
public static final String PRODUCT_TABLE_NAME = "prodcut";
public static final String p_id = "id";
public static final int VERSION =1;
private HashMap hp;
SQLiteDatabase db;
//Context context;
public ShopingCartHelper(Context context)
{
super(context, DATABASE_NAME , null, 1);
}
@Override
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
db = this.getWritableDatabase();
db.execSQL(
"create table prodcut " +
"(id integer primary key, user_id text,product_name text,price text)"
);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// TODO Auto-generated method stub
db.execSQL("DROP TABLE IF EXISTS prodcut");
onCreate(db);
}
public boolean insertProduct (String user_id, String product_name, String price)
{
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put("user_id", user_id);
contentValues.put("product_name", product_name);
contentValues.put("price", price);
db.insert("prodcut", null, contentValues);
return true;
}
public Cursor getData(String user_id){
SQLiteDatabase db = this.getReadableDatabase();
Cursor res = db.rawQuery( "select * from prodcut where user_id="+user_id+"", null );
return res;
}
public int numberOfRows(){
SQLiteDatabase db = this.getReadableDatabase();
int numRows = (int) DatabaseUtils.queryNumEntries(db, PRODUCT_TABLE_NAME);
return numRows;
}
public boolean deleteRec(int pid){
db.delete(PRODUCT_TABLE_NAME, p_id+"="+Integer.toString(pid), null);
return true;
}
}
Exception trace
FATAL EXCEPTION: main java.lang.NullPointerException at
student.briyani.ShopingCartHelper.deleteRec(ShopingCartHelper.java:106) at
student.briyani.cartAdapter$1.onClick(cartAdapter.java:113) at android.view.View.performClick(View.java:3511) at android.view.View$PerformClick.run(View.java:14105) at android.os.Handler.handleCallback(Handler.java:605) at android.os.Handler.dispatchMessage(Handler.java:92) at android.os.Looper.loop(Looper.java:137)
