setAdapter() crashes android app in android studio

setAdapter() crashes android app in android studio - java

I'm following this tutorial (https://www.youtube.com/watch?v=hDSVInZ2JCs&t=3615s&ab_channel=SoftwareandProgrammingwithProfessorSluiter)
Everything works great, until I try this line of code :
lv_productList.setAdapter(productArrayAdapter);
then the app crashes. I've looked online and tried a bunch of stuff but I'm super stuck
Here's the problem area
btn_viewAll.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
DataBaseHelper dataBaseHelper = new DataBaseHelper(MainActivity.this);
List<ProductModel> all = dataBaseHelper.getAll();
ArrayAdapter productArrayAdapter = new ArrayAdapter<ProductModel>(MainActivity.this, android.R.layout.simple_list_item_1, all);
lv_productList.setAdapter(productArrayAdapter);
Toast.makeText(MainActivity.this, all.toString(), Toast.LENGTH_SHORT).show();
}
});
here's my full code
MainActivity.java
package com.example.sqldemo;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.Toast;
import androidx.appcompat.app.AppCompatActivity;
import java.util.List;
public class MainActivity extends AppCompatActivity {
//reference to all buttons and controls on the layout
Button btn_add, btn_viewAll;
EditText et_name, et_number;
ListView lv_productList;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn_add = findViewById(R.id.btn_add);
btn_viewAll = findViewById(R.id.btn_viewAll);
et_name = findViewById(R.id.et_name);
et_number = findViewById(R.id.et_number);
btn_add.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
ProductModel productModel;
try {
productModel = new ProductModel(-1, et_name.getText().toString(), Integer.parseInt(et_number.getText().toString()));
Toast.makeText(MainActivity.this, productModel.toString(), Toast.LENGTH_SHORT).show();
}
catch(Exception err) {
Toast.makeText(MainActivity.this, "Error creating product", Toast.LENGTH_SHORT).show();
productModel = new ProductModel(-1, "error", 0);
}
DataBaseHelper dataBaseHelper = new DataBaseHelper(MainActivity.this);
boolean success = dataBaseHelper.addOne(productModel);
Toast.makeText(MainActivity.this, "Success! Product has been added to the database :)", Toast.LENGTH_SHORT).show();
}
});
btn_viewAll.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
DataBaseHelper dataBaseHelper = new DataBaseHelper(MainActivity.this);
List<ProductModel> all = dataBaseHelper.getAll();
ArrayAdapter productArrayAdapter = new ArrayAdapter<ProductModel>(MainActivity.this, android.R.layout.simple_list_item_1, all);
lv_productList.setAdapter(productArrayAdapter);
Toast.makeText(MainActivity.this, all.toString(), Toast.LENGTH_SHORT).show();
}
});
}
}
DataBaseHelper.java
package com.example.sqldemo;
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 java.util.ArrayList;
import java.util.List;
public class DataBaseHelper extends SQLiteOpenHelper {
public static final String PRODUCT_TABLE = "PRODUCT_TABLE";
public static final String COLUMN_PRODUCT_NAME = "PRODUCT_NAME";
public static final String COLUMN_PRODUCT_NUMBER = "PRODUCT_AGE";
public static final String COLUMN_ID = "ID";
public DataBaseHelper(#Nullable Context context) {
super(context, "Products.db", null, 1);
}
//this is called the first item a database is accessed. used to create a new database
#Override
public void onCreate(SQLiteDatabase db) {
String createTableStatement = "CREATE TABLE " + PRODUCT_TABLE + " (" + COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " + COLUMN_PRODUCT_NAME + " TEXT, " + COLUMN_PRODUCT_NUMBER + " INT)";
db.execSQL(createTableStatement);
}
//this is called if the database version number changes. It prevents previous users apps from breaking when the database is updated
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
public boolean addOne(ProductModel productModel) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues cv = new ContentValues();
cv.put(COLUMN_PRODUCT_NAME, productModel.getName());
cv.put(COLUMN_PRODUCT_NUMBER, productModel.getNumber());
//long insert returns positive in data insertion was successful, and negative if it was not
long insert = db.insert(PRODUCT_TABLE, null, cv);
if (insert == -1) {
return false;
}
else {
return true;
}
}
public List<ProductModel> getAll() {
List<ProductModel> returnList = new ArrayList<>();
// get data from the database
String queryString = "SELECT * FROM " + PRODUCT_TABLE;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(queryString, null);
//move the cursor to the first set of data and check if anything was returned
if (cursor.moveToFirst()) {
// loop through the cursor (result set) and create new product objects. Put them into the return list (defined above)
do {
int productID = cursor.getInt(0);
String productName = cursor.getString(1);
int productNumber = cursor.getInt(2);
ProductModel newProduct = new ProductModel(productID, productName, productNumber);
returnList.add(newProduct);
} while (cursor.moveToNext());
}
else {
//if no results from database, don't add anything to the list.
}
cursor.close();
db.close();
return returnList;
}
}
ProductModel.java
package com.example.sqldemo;
//declare a new public class/object with 3 variables
public class ProductModel {
private int id;
private String name;
private int number;
//constructor
public ProductModel(int id, String name, int number) {
this.id = id;
this.name = name;
this.number = number;
}
public ProductModel() {
}
// toString is necessary for printing the contents of a class object
#Override
public String toString() {
return "ProductModel{" +
"id=" + id +
", name='" + name + '\'' +
", number=" + number +
'}';
}
//getters and setters
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getNumber() {
return number;
}
public void setNumber(int number) {
this.number = number;
}
}
> Blockquote

You can simply change RecyclerView to ListView.
Or
if you want to use RecyclerView, you have to create a custom Recyclerview Adapter.
Here a Beginner friendly Guide: https://medium.com/#suhanshupatel/recyclerview-in-android-for-beginner-cfbc132a0dec

Related

ListView editable OnLongClickListener

I have been searching for hours but still I can't find any way on how to update a listview using the listview.setOnItemLongClickListener I have tried but I think I am doing it all wrong. Does anyone know how to edit a listview after a longclick listener?
DBHelper
public class DBHelper extends SQLiteOpenHelper {
public static final String TEST_TABLE = "TEST_TABLE";
public static final String TEST_NAME = "NAME";
public static final String COLUMN_NAME = TEST_NAME;
public static final String COLUMN_ADDRESS = "ADDRESS";
public static final String COLUMN_ID = "ID";
public static final String TEST_AGE = "age";
public DBHelper(#Nullable Context context) {
super(context, "test.db", null, 1);
}
#Override
public void onCreate(SQLiteDatabase sqLiteDatabase) {
String createTableStatement = "CREATE TABLE " + TEST_TABLE + " (" + COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " + COLUMN_NAME + " TEXT, " + COLUMN_ADDRESS + " TEXT)";
sqLiteDatabase.execSQL(createTableStatement);
}
#Override
public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {
}
public boolean addData(TestModel testModel) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues cv = new ContentValues();
cv.put(COLUMN_NAME, testModel.getName());
cv.put(COLUMN_ADDRESS, testModel.getAddress());
long insert = db.insert(TEST_TABLE, null, cv);
if (insert == -1) {
return false;
} else {
return true;
}
}
public boolean deleteData(TestModel testModel) {
SQLiteDatabase db = this.getWritableDatabase();
String queryString = "DELETE FROM " + TEST_TABLE + " WHERE " + COLUMN_ID + " = " + testModel.getID();
Cursor cursor = db.rawQuery(queryString, null);
if (cursor.moveToFirst()) {
return true;
} else {
return false;
}
}
public void update(TestModel testModel) {
}
public List<TestModel> viewAll() {
List<TestModel> returnList = new ArrayList<>();
String queryString = "SELECT * FROM " + TEST_TABLE;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(queryString, null);
if (cursor.moveToFirst()) {
do {
int id = cursor.getInt(0);
String name = cursor.getString(1);
String address = cursor.getString(2);
TestModel newTest = new TestModel(id, name, address);
returnList.add(newTest);
} while (cursor.moveToNext());
} else {
}
cursor.close();
db.close();
return returnList;
}
}
TestModel
public class TestModel {
private int ID;
private String name;
private String address;
public TestModel(int ID, String name, String address) {
this.ID = ID;
this.name = name;
this.address = address;
}
#Override
public String toString() {
return "ID:" + ID +
", name:'" + name + '\'' +
", address:'" + address + '\'' +
'}';
}
public TestModel() {
}
public int getID() {
return ID;
}
public void setID(int ID) {
this.ID = ID;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
}
MainActivity
package com.example.crudtest2;
import androidx.appcompat.app.AppCompatActivity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.database.Cursor;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.Toast;
import java.util.List;
public class MainActivity extends AppCompatActivity {
Button btn_Add, btn_View;
EditText et_name, et_address, et_username;
ListView lv_allList;
ArrayAdapter testArrayAdapter;
DBHelper dbHelper;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn_Add = findViewById(R.id.btnAdd);
btn_View = findViewById(R.id.btnView);
et_name = findViewById(R.id.inputName);
et_address = findViewById(R.id.inputAddress);
lv_allList = findViewById(R.id.listviewData);
dbHelper = new DBHelper(MainActivity.this);
showAllData(dbHelper);
btn_Add.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
TestModel testModel;
try {
testModel = new TestModel(-1, et_name.getText().toString(), et_address.getText().toString());
Toast.makeText(MainActivity.this, "Successfully Added", Toast.LENGTH_SHORT).show();
} catch (Exception e) {
Toast.makeText(MainActivity.this, "Error adding", Toast.LENGTH_SHORT).show();
testModel = new TestModel(-1, "error", "error");
}
DBHelper dbHelper = new DBHelper(MainActivity.this);
dbHelper.addData(testModel);
showAllData(dbHelper);
}
});
btn_View.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
DBHelper dbHelper = new DBHelper(MainActivity.this);
showAllData(dbHelper);
//Toast.makeText(MainActivity.this, dbHelper.viewAll().toString(), Toast.LENGTH_SHORT).show();
}
});
lv_allList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
TestModel clickedData = (TestModel) adapterView.getItemAtPosition(i);
dbHelper.deleteData(clickedData);
showAllData(dbHelper);
Toast.makeText(MainActivity.this, "Data Deleted Successfully", Toast.LENGTH_SHORT).show();
}
});
lv_allList.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
#Override
public boolean onItemLongClick(AdapterView<?> adapterView, View view, int i, long l) {
TestModel clickedData = (TestModel) adapterView.getItemAtPosition(i);
dbHelper.updateData(clickedData);
return true;
}
});
}
private void showAllData(DBHelper dbHelper) {
testArrayAdapter = new ArrayAdapter<TestModel>(MainActivity.this, android.R.layout.simple_list_item_1, dbHelper.viewAll());
lv_allList.setAdapter(testArrayAdapter);
}
}
Is there like any way to edit my listview once a longclick listener event has happened? I have tried doing the same thing with delete it's because I don't have really any idea how to edit a listview after a longclick.

How to implement searchview in recyclerview which based on SQLite? - Android

I am Building Android application which stores the patient details in SQLite database and shows this data in recyclerview, Now i want to add searchview for my recyclerview, plz help me to implement this one.
I am working on this project with the help of this youtube tutorial Series - https://youtube.com/playlist?list=PLSrm9z4zp4mGK0g_0_jxYGgg3os9tqRUQ
Here is my MainActivity Class
import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import android.content.Intent;
import android.database.Cursor;
import android.os.Bundle;
import android.view.View;
import android.widget.Toast;
import com.google.android.material.floatingactionbutton.FloatingActionButton;
import java.util.ArrayList;
public class MainActivity extends AppCompatActivity {
RecyclerView recyclerView;
FloatingActionButton add_button;
MyDatabaseHelper myDB;
ArrayList<String> _id, name, disease, medicine, mobile, address, day, month, year;
CustomAdapter customAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
recyclerView = findViewById(R.id.recyclerView);
add_button = findViewById(R.id.add_button);
add_button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, AddActivity.class);
startActivity(intent);
}
});
myDB = new MyDatabaseHelper(MainActivity.this);
_id = new ArrayList<>();
name = new ArrayList<>();
disease = new ArrayList<>();
medicine = new ArrayList<>();
mobile = new ArrayList<>();
address = new ArrayList<>();
day = new ArrayList<>();
month = new ArrayList<>();
year = new ArrayList<>();
storeDataInArrays();
customAdapter = new CustomAdapter(MainActivity.this, _id, name, disease, medicine, mobile, address, day, month, year);
recyclerView.setAdapter(customAdapter);
recyclerView.setLayoutManager(new LinearLayoutManager(MainActivity.this));
}
void storeDataInArrays(){
Cursor cursor = myDB.readAllData();
if(cursor.getCount() == 0){
Toast.makeText(this, "No data.", Toast.LENGTH_SHORT).show();
}else{
while (cursor.moveToNext()){
_id.add(cursor.getString(0));
name.add(cursor.getString(1));
disease.add(cursor.getString(2));
medicine.add(cursor.getString(3));
mobile.add(String.valueOf(cursor.getLong(4)));
address.add(cursor.getString(5));
day.add(cursor.getString(6));
month.add(cursor.getString(7));
year.add(cursor.getString(8));
}
}
}
}
here is my AddActivity Class
package com.example.myclinic;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import androidx.appcompat.app.AppCompatActivity;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
public class AddActivity extends AppCompatActivity {
EditText name_input, disease_input, medicine_input, mobile_input, address_input, day_input, month_input, year_input;
Button add_button;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_add);
name_input = findViewById(R.id.name_input);
disease_input = findViewById(R.id.disease_input);
medicine_input = findViewById(R.id.medicine_input);
mobile_input = findViewById(R.id.mobile_input);
address_input = findViewById(R.id.address_input);
day_input = findViewById(R.id.day_input);
month_input = findViewById(R.id.month_input);
year_input = findViewById(R.id.year_input);
add_button = findViewById(R.id.add_button);
Date date = new Date();
SimpleDateFormat formatter = new SimpleDateFormat("dd/MM/yyyy");
String strDate = formatter.format(date);
day_input.setText(strDate.substring(0,2));
month_input.setText(strDate.substring(3,5));
year_input.setText(strDate.substring(6,10));
add_button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (TextUtils.isEmpty(name_input.getText().toString()) || TextUtils.isEmpty(disease_input.getText().toString())) {
name_input.setHint("Patient Name* (Mandatory)");
disease_input.setHint("Disease* (Mandatory)");
Toast.makeText(AddActivity.this,
"Failed!", Toast.LENGTH_SHORT).show();
} else {
try {
MyDatabaseHelper myDB = new MyDatabaseHelper(AddActivity.this);
myDB.addPatient(name_input.getText().toString().trim(),
disease_input.getText().toString().trim(),
medicine_input.getText().toString().trim(),
Long.parseLong("0" + mobile_input.getText().toString().trim()),
address_input.getText().toString().trim(),
Integer.parseInt(day_input.getText().toString().trim()),
Integer.parseInt(month_input.getText().toString().trim()),
Integer.parseInt(year_input.getText().toString().trim()));
} catch (Exception e) {
Toast.makeText(AddActivity.this, "Failed!", Toast.LENGTH_SHORT).show();
}
}
}
});
}
}
here is MyDatabaseHelper Class
package com.example.myclinic;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.widget.Toast;
import androidx.annotation.Nullable;
import com.google.android.material.shape.ShapeAppearanceModel;
public class MyDatabaseHelper extends SQLiteOpenHelper {
private Context context;
private static final String DATABASE_NAME = "PatientList.db";
private static final int DATABASE_VERSION = 1;
private static final String TABLE_NAME = "patients";
private static final String COLUMN_ID = "_id";
private static final String COLUMN_NAME = "name";
private static final String COLUMN_DISEASE = "disease";
private static final String COLUMN_MEDICINES = "medicines";
private static final String COLUMN_MOBILE = "mobile";
private static final String COLUMN_ADDRESS = "address";
private static final String COLUMN_DAY = "day";
private static final String COLUMN_MONTH = "month";
private static final String COLUMN_YEAR = "year";
public MyDatabaseHelper(#Nullable Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
this.context = context;
}
#Override
public void onCreate(SQLiteDatabase db) {
String query =
"CREATE TABLE " + TABLE_NAME +
" (" + COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
COLUMN_NAME + " TEXT, " +
COLUMN_DISEASE + " TEXT, " +
COLUMN_MEDICINES + " TEXT, " +
COLUMN_MOBILE + " INTEGER, " +
COLUMN_ADDRESS + " TEXT, " +
COLUMN_DAY + " INTEGER, " +
COLUMN_MONTH + " INTEGER, " +
COLUMN_YEAR + " INTEGER);";
db.execSQL(query);
}
#Override
public void onUpgrade(SQLiteDatabase db, int i, int i1) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
onCreate(db);
}
void addPatient(String pname, String pdisease, String pmedicines, Long pmobile, String paddress, int pday, int pmonth, int pyear){
SQLiteDatabase db = this.getWritableDatabase();
ContentValues cv = new ContentValues();
cv.put(COLUMN_NAME, pname);
cv.put(COLUMN_DISEASE, pdisease);
cv.put(COLUMN_MEDICINES, pmedicines);
cv.put(COLUMN_MOBILE, pmobile.longValue());
cv.put(COLUMN_ADDRESS, paddress);
cv.put(COLUMN_DAY, pday);
cv.put(COLUMN_MONTH, pmonth);
cv.put(COLUMN_YEAR, pyear);
long result = db.insert(TABLE_NAME, null, cv);
if(result == -1) {
Toast.makeText(context, "Failed!", Toast.LENGTH_SHORT).show();
}else{
Toast.makeText(context, "Added Successfully...", Toast.LENGTH_SHORT).show();
}
}
Cursor readAllData(){
String query = "SELECT * FROM " + TABLE_NAME;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = null;
if(db != null) cursor = db.rawQuery(query, null);
return cursor;
}
}
here is CustomAdapter Class
package com.example.myclinic;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
import java.security.PrivateKey;
import java.util.ArrayList;
public class CustomAdapter extends RecyclerView.Adapter<CustomAdapter.MyViewHolder> {
private Context context;
private ArrayList _id, name, disease, medicine, mobile, address, day, month, year;
CustomAdapter(Context context, ArrayList _id, ArrayList name, ArrayList disease,
ArrayList medicine, ArrayList mobile, ArrayList address, ArrayList day, ArrayList month, ArrayList year){
this.context = context;
this._id = _id;
this.name = name;
this.disease = disease;
this.medicine = medicine;
this.mobile = mobile;
this.address = address;
this.day = day;
this.month = month;
this.year = year;
}
#NonNull
#Override
public MyViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
LayoutInflater inflater = LayoutInflater.from(context);
View view = inflater.inflate(R.layout.my_row, parent, false);
return new MyViewHolder(view);
}
#Override
public void onBindViewHolder(#NonNull MyViewHolder holder, int position) {
holder.id_txt.setText(String.valueOf(_id.get(position)));
holder.name_txt.setText(String.valueOf(name.get(position)));
holder.disease_txt.setText(String.valueOf(disease.get(position)));
holder.medicine_txt.setText(String.valueOf(medicine.get(position)));
holder.mobile_txt.setText(String.valueOf(mobile.get(position)));
holder.address_txt.setText(String.valueOf(address.get(position)));
holder.day_txt.setText(String.valueOf(day.get(position)));
holder.month_txt.setText(String.valueOf(month.get(position)));
holder.year_txt.setText(String.valueOf(year.get(position)));
}
#Override
public int getItemCount() {
return _id.size();
}
public class MyViewHolder extends RecyclerView.ViewHolder {
TextView id_txt, name_txt, disease_txt, medicine_txt, mobile_txt, address_txt, day_txt, month_txt, year_txt;
public MyViewHolder(#NonNull View itemView) {
super(itemView);
id_txt = itemView.findViewById(R.id.id_txt);
name_txt = itemView.findViewById(R.id.name_txt);
disease_txt = itemView.findViewById(R.id.disease_txt);
medicine_txt = itemView.findViewById(R.id.medicine_txt);
mobile_txt = itemView.findViewById(R.id.mobile_txt);
address_txt = itemView.findViewById(R.id.address_txt);
day_txt = itemView.findViewById(R.id.day_txt);
month_txt = itemView.findViewById(R.id.month_txt);
year_txt = itemView.findViewById(R.id.year_txt);
}
}
}

For Implementing search functionality in this project, as #thinkgruen suggested me that i need to work on single arraylist instead of multiple arraylist thats why i created separate class having all my data and made arraylist of that class, and implemented filter method to that arraylist.
After that i gone throgh this youtube tutorial - https://www.youtube.com/watch?v=CTvzoVtKoJ8
I'm posting changed code here, i made old code as a comment and changed code marked as //U . Beacuse U can clearly see what changes i have made.
at first here is new class - PatientList
package com.example.myclinic;
public class PatientList {
private int _id;
private String name;
private String disease;
private String medicine;
private long mobile;
private String address;
private int day;
private int month;
private int year;
private String serialid;
public int getid() {
return _id;
}
public void setid(int _id) {
this._id = _id;
}
public String getname() {
return name;
}
public void setname (String name) {
this.name = name;
}
public String getdisease() {
return disease;
}
public void setdisease (String disease) {
this.disease = disease;
}
public String getmedicine() {
return medicine;
}
public void setmedicine (String medicine) {
this.medicine = medicine;
}
public long getmobile() {
return mobile;
}
public void setmobile (long mobile) {
this.mobile = mobile;
}
public String getaddress() {
return address;
}
public void setaddress (String address) {
this.address = address;
}
public int getday() {
return day;
}
public void setday(int day) {
this.day = day;
}
public int getmonth() {
return month;
}
public void setmonth(int month) {
this.month = month;
}
public int getyear() {
return year;
}
public void setyear(int year) {
this.year = year;
}
public String getserialid() {
return serialid;
}
public void setserialid (String serialid) {
this.serialid = serialid;
}
//constructor
public PatientList(int _id, String name, String disease, String medicine, long mobile, String address, int day, int month, int year, String serialid){
this._id = _id;
this.name = name;
this.disease = disease;
this.medicine = medicine;
this.mobile = mobile;
this.address = address;
this.day = day;
this.month = month;
this.year = year;
this.serialid = serialid;
}
}
After that, in Class - CustomAdapter
package com.example.myclinic;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Filter;
import android.widget.Filterable;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
//U
public class CustomAdapter extends RecyclerView.Adapter<CustomAdapter.MyViewHolder> implements Filterable {
private Context context;
// private ArrayList _id, name, disease, medicine, mobile, address, day, month, year, serialid;
private List<PatientList> patientList = new ArrayList<>(); //U
private List<PatientList> patientListAll = new ArrayList<>();
CustomAdapter(Context context,/* ArrayList _id, ArrayList name, ArrayList disease,
ArrayList medicine, ArrayList mobile, ArrayList address, ArrayList day, ArrayList month, ArrayList year, ArrayList serialid, */
ArrayList<PatientList> patientList){
this.context = context;
/*
this._id = _id;
this.name = name;
this.disease = disease;
this.medicine = medicine;
this.mobile = mobile;
this.address = address;
this.day = day;
this.month = month;
this.year = year;
this.serialid = serialid;
*/
this.patientList = patientList; //U
this.patientListAll = new ArrayList<>(patientList);
}
#NonNull
#Override
public MyViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
LayoutInflater inflater = LayoutInflater.from(context);
View view = inflater.inflate(R.layout.my_row, parent, false);
return new MyViewHolder(view);
}
#Override
public void onBindViewHolder(#NonNull MyViewHolder holder, int position) {
/*
holder.id_txt.setText(String.valueOf(_id.get(position)));
holder.name_txt.setText(String.valueOf(name.get(position)));
holder.disease_txt.setText(String.valueOf(disease.get(position)));
holder.medicine_txt.setText(String.valueOf(medicine.get(position)));
holder.mobile_txt.setText(String.valueOf(mobile.get(position)));
holder.address_txt.setText(String.valueOf(address.get(position)));
holder.day_txt.setText(String.valueOf(day.get(position)));
holder.month_txt.setText(String.valueOf(month.get(position)));
holder.year_txt.setText(String.valueOf(year.get(position)));
holder.serialid_txt.setText(String.valueOf(serialid.get(position)));
*/
PatientList plist = patientList.get(position); //U
holder.id_txt.setText(String.valueOf(plist.getid()));
holder.name_txt.setText(String.valueOf(plist.getname()));
holder.disease_txt.setText(String.valueOf(plist.getdisease()));
holder.medicine_txt.setText(String.valueOf(plist.getmedicine()));
holder.mobile_txt.setText(String.valueOf(plist.getmobile()));
holder.address_txt.setText(String.valueOf(plist.getaddress()));
holder.day_txt.setText(String.valueOf(plist.getday()));
holder.month_txt.setText(String.valueOf(plist.getmonth()));
holder.year_txt.setText(String.valueOf(plist.getyear()));
holder.serialid_txt.setText(String.valueOf(plist.getserialid()));
}
#Override
public int getItemCount() {
return patientList.size();
}
//U
#Override
public Filter getFilter() {
return filter;
}
//U
Filter filter = new Filter() {
#Override
protected FilterResults performFiltering(CharSequence constaint) {
List<PatientList> filteredList = new ArrayList<>();
if (constaint.toString().isEmpty()) {
filteredList.addAll(patientListAll);
} else {
for (PatientList patient : patientListAll) {
if (patient.getname().toLowerCase().contains(constaint.toString().toLowerCase())
|| patient.getserialid().toLowerCase().contains(constaint.toString().toLowerCase())
|| patient.getaddress().toLowerCase().contains(constaint.toString().toLowerCase())) {
filteredList.add(patient);
}
}
}
FilterResults filterResults = new FilterResults();
filterResults.values = filteredList;
return filterResults;
}
#Override
protected void publishResults(CharSequence constraint, FilterResults filterResults) {
patientList.clear();
patientList.addAll((Collection<? extends PatientList>) filterResults.values);
notifyDataSetChanged();
}
};
public class MyViewHolder extends RecyclerView.ViewHolder {
TextView id_txt, name_txt, disease_txt, medicine_txt, mobile_txt, address_txt, day_txt, month_txt, year_txt, serialid_txt;
public MyViewHolder(#NonNull View itemView) {
super(itemView);
id_txt = itemView.findViewById(R.id.id_txt);
name_txt = itemView.findViewById(R.id.name_txt);
disease_txt = itemView.findViewById(R.id.disease_txt);
medicine_txt = itemView.findViewById(R.id.medicine_txt);
mobile_txt = itemView.findViewById(R.id.mobile_txt);
address_txt = itemView.findViewById(R.id.address_txt);
day_txt = itemView.findViewById(R.id.day_txt);
month_txt = itemView.findViewById(R.id.month_txt);
year_txt = itemView.findViewById(R.id.year_txt);
serialid_txt = itemView.findViewById(R.id.serialid_txt);
}
}
}
Class DatabaseHelper
package com.example.myclinic;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.widget.Toast;
import androidx.annotation.Nullable;
import com.google.android.material.shape.ShapeAppearanceModel;
public class MyDatabaseHelper extends SQLiteOpenHelper {
private Context context;
private static final String DATABASE_NAME = "PatientList.db";
private static final int DATABASE_VERSION = 1;
private static final String TABLE_NAME = "patients";
private static final String COLUMN_ID = "_id";
private static final String COLUMN_NAME = "name";
private static final String COLUMN_DISEASE = "disease";
private static final String COLUMN_MEDICINES = "medicines";
private static final String COLUMN_MOBILE = "mobile";
private static final String COLUMN_ADDRESS = "address";
private static final String COLUMN_DAY = "day";
private static final String COLUMN_MONTH = "month";
private static final String COLUMN_YEAR = "year";
private static final String COLUMN_SERIALID = "serialid";
public MyDatabaseHelper(#Nullable Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
this.context = context;
}
#Override
public void onCreate(SQLiteDatabase db) {
String query =
"CREATE TABLE " + TABLE_NAME +
" (" + COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
COLUMN_NAME + " TEXT, " +
COLUMN_DISEASE + " TEXT, " +
COLUMN_MEDICINES + " TEXT, " +
COLUMN_MOBILE + " INTEGER, " +
COLUMN_ADDRESS + " TEXT, " +
COLUMN_DAY + " INTEGER, " +
COLUMN_MONTH + " INTEGER, " +
COLUMN_YEAR + " INTEGER, " +
COLUMN_SERIALID + " TEXT);";
db.execSQL(query);
}
#Override
public void onUpgrade(SQLiteDatabase db, int i, int i1) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
onCreate(db);
}
void addPatient(String pname, String pdisease, String pmedicines, Long pmobile, String paddress, int pday, int pmonth, int pyear, String pserialid){
SQLiteDatabase db = this.getWritableDatabase();
ContentValues cv = new ContentValues();
cv.put(COLUMN_NAME, pname);
cv.put(COLUMN_DISEASE, pdisease);
cv.put(COLUMN_MEDICINES, pmedicines);
cv.put(COLUMN_MOBILE, pmobile.longValue());
cv.put(COLUMN_ADDRESS, paddress);
cv.put(COLUMN_DAY, pday);
cv.put(COLUMN_MONTH, pmonth);
cv.put(COLUMN_YEAR, pyear);
cv.put(COLUMN_SERIALID, pserialid);
long result = db.insert(TABLE_NAME, null, cv);
if(result == -1) {
Toast.makeText(context, "Failed!", Toast.LENGTH_SHORT).show();
}else{
Toast.makeText(context, "Added Successfully...", Toast.LENGTH_SHORT).show();
}
}
Cursor readAllData(){
String query = "SELECT * FROM " + TABLE_NAME;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = null;
if(db != null) cursor = db.rawQuery(query, null);
return cursor;
}
}
And Final changes in MainActivity.Java
package com.example.myclinic;
import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import androidx.appcompat.widget.SearchView;
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.Toast;
import com.google.android.material.floatingactionbutton.FloatingActionButton;
import java.util.ArrayList;
public class MainActivity extends AppCompatActivity {
RecyclerView recyclerView;
FloatingActionButton add_button;
MyDatabaseHelper myDB;
// ArrayList<String> _id, name, disease, medicine, mobile, address, day, month, year, serialid;
ArrayList<PatientList> patientList = new ArrayList<>(); //U
CustomAdapter customAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
recyclerView = findViewById(R.id.recyclerView);
add_button = findViewById(R.id.add_button);
add_button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, AddActivity.class);
startActivity(intent);
}
});
myDB = new MyDatabaseHelper(MainActivity.this);
/*
_id = new ArrayList<>();
name = new ArrayList<>();
disease = new ArrayList<>();
medicine = new ArrayList<>();
mobile = new ArrayList<>();
address = new ArrayList<>();
day = new ArrayList<>();
month = new ArrayList<>();
year = new ArrayList<>();
serialid = new ArrayList<>();
*/
storeDataInArray();
customAdapter = new CustomAdapter(MainActivity.this, patientList);
recyclerView.setAdapter(customAdapter);
recyclerView.setLayoutManager(new LinearLayoutManager(MainActivity.this));
}
/*
void storeDataInArrays(){
Cursor cursor = myDB.readAllData();
if(cursor.getCount() == 0){
Toast.makeText(this, "No data.", Toast.LENGTH_SHORT).show();
}else{
while (cursor.moveToNext()){
_id.add(cursor.getString(0));
name.add(cursor.getString(1));
disease.add(cursor.getString(2));
medicine.add(cursor.getString(3));
mobile.add(String.valueOf(cursor.getLong(4)));
address.add(cursor.getString(5));
day.add(cursor.getString(6));
month.add(cursor.getString(7));
year.add(cursor.getString(8));
serialid.add(cursor.getString(9));
}
}
} */
void storeDataInArray(){ //U
Cursor cursor = myDB.readAllData();
if(cursor.getCount() == 0){
Toast.makeText(this, "No data.", Toast.LENGTH_SHORT).show();
}else{
while (cursor.moveToNext()){
patientList.add(new PatientList(cursor.getInt(0),
cursor.getString(1),
cursor.getString(2),
cursor.getString(3),
cursor.getLong(4),
cursor.getString(5),
cursor.getInt(6),
cursor.getInt(7),
cursor.getInt(8),
cursor.getString(9)));
}
}
}
#Override //U
public boolean onCreateOptionsMenu(Menu menu)
{
getMenuInflater().inflate(R.menu.mainmenu, menu);
MenuItem item = menu.findItem(R.id.action_search);
SearchView searchView = (SearchView)item.getActionView();
searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
#Override
public boolean onQueryTextSubmit(String query) {
return false;
}
#Override
public boolean onQueryTextChange(String newText) {
customAdapter.getFilter().filter(newText);
return false;
}
});
return super.onCreateOptionsMenu(menu);
}
}
nothing changed in AddActivity.
I hope this will be helpfull to you.

How to Retrieve Multiple data when clicked on listview?

I want all edit text content that I have saved in SQL to be displayed on the edit bills activity when I click on the list item, but I am only able to retrieve the name and display it again in the intent. Rather than saving another data it should update the record with the new data if I save the existing record another time in the editbills_activity.
Here is my DBAdapter.java
package com.example.dhruv.bills;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
public class DBAdapter {
public static final String KEY_ROWID = "id";
public static final String KEY_NAME = "name";
public static final String KEY_AMOUNT = "amount";
public static final String KEY_DUEDATE = "duedate";
private static final String TAG = "DBAdapter";
private static final String DATABASE_NAME = "billsdb";
private static final String DATABASE_TABLE = "bills";
private static final int DATABASE_VERSION = 2;
private static final String DATABASE_CREATE =
"create table if not exists assignments (id integer primary key autoincrement, "
+ "name VARCHAR not null, amount VARCHAR, duedate date );";
// Replaces DATABASE_CREATE using the one source definition
private static final String TABLE_CREATE =
"CREATE TABLE IF NOT EXISTS " + DATABASE_TABLE + "(" +
KEY_ROWID + " INTEGER PRIMARY KEY, " + // AUTOINCREMENT NOT REQD
KEY_NAME + " DATE NOT NULL, " +
KEY_AMOUNT + " VARCHAR ," +
KEY_DUEDATE + " DATE " +
")";
private final Context context;
private DatabaseHelper DBHelper;
private SQLiteDatabase db;
public DBAdapter(Context ctx)
{
this.context = ctx;
DBHelper = new DatabaseHelper(context);
}
private static class DatabaseHelper extends SQLiteOpenHelper
{
DatabaseHelper(Context context)
{
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db)
{
db.execSQL(TABLE_CREATE); // NO need to encapsulate in try clause
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)
{
Log.w(TAG, "Upgrading database from version " + oldVersion + " to "
+ newVersion + ", which will destroy all old data");
db.execSQL("DROP TABLE IF EXISTS contacts"); //????????
db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE);
onCreate(db);
}
}
//---opens the database---
public DBAdapter open() throws SQLException
{
db = DBHelper.getWritableDatabase();
return this;
}
//---closes the database---
public void close()
{
DBHelper.close();
}
//---insert a record into the database---
public long insertRecord(String name, String amount, String duedate)
{
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_NAME, name);
initialValues.put(KEY_AMOUNT, amount);
initialValues.put(KEY_DUEDATE, duedate);
//return db.insert(DATABASE_TABLE, null, initialValues);
// Will return NULL POINTER EXCEPTION as db isn't set
// Replaces commented out line
return DBHelper.getWritableDatabase().insert(DATABASE_TABLE,
null,
initialValues
);
}
//---deletes a particular record---
public boolean deleteContact(long rowId)
{
return db.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0;
}
//---retrieves all the records--- SEE FOLLOWING METHOD
public Cursor getAllRecords()
{SQLiteDatabase db = DBHelper.getWritableDatabase();
String query ="SELECT * FROM " + DATABASE_TABLE;
Cursor data = db.rawQuery(query,null);
return data;
}
//As per getAllRecords but using query convenience method
public Cursor getAllAsCursor() {
return DBHelper.getWritableDatabase().query(
DATABASE_TABLE,
null,null,null,null,null,null
);
}
public Cursor getItemID(String name) {
SQLiteDatabase db = DBHelper.getWritableDatabase();
String query = "SELECT " + KEY_ROWID + " FROM " + DATABASE_TABLE +
" WHERE " + KEY_NAME + " = '" + name + "'";
Cursor data = db.rawQuery(query, null);
return data;
}
//---retrieves a particular record--- THIS WILL NOT WORK - NO SUCH TABLE
/* public Cursor getRecord()
{String query1 ="SELECT * FROM" + KEY_TITLE;
Cursor mCursor = db.rawQuery(query1,null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}*/
// Retrieve a row (single) according to id
public Cursor getRecordById(long id) {
return DBHelper.getWritableDatabase().query(
DATABASE_TABLE,
null,
KEY_ROWID + "=?",
new String[]{String.valueOf(id)},
null,null,null
);
}
//---updates a record---
/* public boolean updateRecord(long rowId, String name, String amount, String duedate)
{
ContentValues args = new ContentValues();
args.put(KEY_NAME, name);
args.put(KEY_AMOUNT, amount);
args.put(KEY_DUEDATE, duedate);
String whereclause = KEY_ROWID + "=?";
String[] whereargs = new String[]{String.valueOf(rowId)};
// Will return NULL POINTER EXCEPTION as db isn't set
//return db.update(DATABASE_TABLE, args, KEY_ROWID + "=" + rowId, null) > 0;
// Replaces commented out line
return DBHelper.getWritableDatabase().update(DATABASE_TABLE,
args,
whereclause,
whereargs
) > 0;
}*/
}
Here is my Bills.java
(MainActivity)
Problem: Bills.java has the list view that shows the intent whenever the item in list view is clicked, but it does not put the amount and date or update the record. Instead it saves another record.
Solution: I want to retrieve it and display all (name ,amount,duedate) and instead of saving another record it should update it.
package com.example.dhruv.bills;
import android.content.Intent;
import android.database.Cursor;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.Toast;
import java.util.ArrayList;
public class bills extends AppCompatActivity {
DBAdapter dbAdapter;
ListView mrecycleview;
private static final String TAG ="assignments";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_bills);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
mrecycleview =(ListView) findViewById(R.id.mRecycleView);
dbAdapter = new DBAdapter(this);
// mlistview();
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent i = new Intent(getApplicationContext(),Editbills.class);
startActivity(i);
}
});
mlistview();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_bills, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
private void mlistview(){
Log.d(TAG,"mlistview:Display data in listview");
Cursor mCursor = dbAdapter.getAllRecords();
ArrayList<String> listData = new ArrayList<>();
while (mCursor.moveToNext()){
listData.add(mCursor.getString(1));
}
ListAdapter adapter = new ArrayAdapter<>(this,android.R.layout.simple_list_item_1,listData);
mrecycleview.setAdapter(adapter);
mrecycleview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
String name = adapterView.getItemAtPosition(i).toString();
Log.d(TAG, "onItemClick: You Clicked on " + name);
Cursor data = dbAdapter.getItemID(name); //get the id associated with that name
int itemID = -1;
while(data.moveToNext()){
itemID = data.getInt(0);
}
if(itemID > -1){
Log.d(TAG, "onItemClick: The ID is: " + itemID);
Intent editScreenIntent = new Intent(bills.this, Editbills.class);
editScreenIntent.putExtra("id",itemID);
editScreenIntent.putExtra("name",name);
startActivity(editScreenIntent);
}
else{
}
}
});
}
}
here is my editbills.java code
package com.example.dhruv.bills;
import android.content.ContentValues;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.Toast;
import java.util.ArrayList;
public class Editbills extends AppCompatActivity {
Button button;
private static final String Tag= "assignments";
DBAdapter db = new DBAdapter(this);
private String selectedName;
private int selectedID;
DBAdapter dbAdapter;
private EditText editText,editText2,editText3;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_editbills);
button=(Button)findViewById(R.id.button);
editText =(EditText)findViewById(R.id.editText);
editText2=(EditText)findViewById(R.id.editText2);
editText3 =(EditText)findViewById(R.id.editText3);
//get the intent extra from the ListDataActivity
Intent receivedIntent = getIntent();
//now get the itemID we passed as an extra
selectedID = receivedIntent.getIntExtra("id",-1); //NOTE: -1 is just the default value
//now get the name we passed as an extra
selectedName = receivedIntent.getStringExtra("name");
//set the text to show the current selected name
editText.setText(selectedName);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Log.d("test", "adding");
db.open();
long id = db.insertRecord(editText.getText().toString(), editText2.getText().toString(), editText3.getText().toString());
db.close();
Toast.makeText(Editbills.this," Added", Toast.LENGTH_LONG).show();
Intent q = new Intent(getApplicationContext(),bills.class);
startActivity(q);
}
});
}
}

There are two parts/questions.
First to retrieve the data, so that it can be displayed in the editbills activity, you can utilise the row's id that is passed to the activity in conjunction with the getRecordById method.
I'd suggest that adding a method to the editbills class will simplyfy matters.
private void populateDisplay(int id) {
Cursor csr = dbAdapter.getRecordById(id);
if (csr.moveToFirst()) {
editText.setText(csr.getString(csr.getColumnIndex(DBAdapter.KEY_NAME)));
editText2.setText(csr.getString(csr.getColumnIndex(DBAdapter.KEY_AMOUNT)));
editText3.setText(csr.getString(csr.getColumnIndex(DBAdapter.KEY_DUEDATE)));
}
csr.close();
}
You could invoke the above method after retrieving the id from the Intent using :-
populateDisplay(selectedID);
To update based upon the content's of the EditTexts un-comment the updateRecord method in DBAdapter.java and the change :-
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Log.d("test", "adding");
db.open();
long id = db.insertRecord(editText.getText().toString(), editText2.getText().toString(), editText3.getText().toString());
db.close();
Toast.makeText(Editbills.this," Added", Toast.LENGTH_LONG).show();
Intent q = new Intent(getApplicationContext(),bills.class);
startActivity(q);
}
});
to :-
mButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (dbAdapter.updateRecord(
selectedId,
editText.getText().toString(),
editText2.getText().toString(),
editText3.getText().toString())
) {
Log.d("TEST","Row successfully updated.");
Toast.makeText(getApplicationContext(),"Row Updated.",Toast.LENGTH_LONG).show();
populateDisplay(selectedId);
} else {
Toast.makeText(getApplicationContext(),"Row not Updated",Toast.LENGTH_LONG).show();
}
Intent q = new Intent(getApplicationContext(),bills.class);
startActivity(q);
}
});
You will additionally have to add a line initialise the dbAdapter i.e. dbAdapter = new DBAdapter(this); i.d suggest adding this line immediately after the line setContentView(R.layout.activity_editbills);
Note the above code is in-principle and has not been thoroughly tested so it may contains errors.
Edit complete working example :-
The following code is basically an implementation of the above, except modified to utilise a Bill class. Rather than an ArrayList<String> as the source for the Adapter it has ArrayList<Bill>.
Thus all the data (id, name, amount and duedate) is available.
You should notice that I've overridden the toString method to return a String that combines the name, amount and duedate. The ArrayAdapter uses the object's toString method to populate the view.
Saying that the critical value is the rowid or an alias of rowid as this can be used to identify a row even if the other data is identical (as would happen when running this example more than once due to the addSomeData method). Hence, only the id is extracted and passed to the Editbills activity when an item in the list is long clicked (changed from just clicked to reduce the potential for accidental use).
Bill.java
public class Bill {
private long id;
private String name;
private String amount;
private String duedate;
public Bill(long id, String name, String amount, String duedate) {
this.id = id;
this.name = name;
this.amount = amount;
this.duedate = duedate;
}
/*
Note if this Constructor used then setId should be used
*/
public Bill(String name, String amount, String duedate) {
new Bill(0,name,amount,duedate);
}
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getAmount() {
return amount;
}
public void setAmount(String amount) {
this.amount = amount;
}
public String getDuedate() {
return duedate;
}
public void setDuedate(String duedate) {
this.duedate = duedate;
}
/*
As ArrayAdapter uses toString method change this
to return all items
*/
#Override
public String toString() {
return name + " " + amount + " " + duedate;
}
}
MainActivity.java
This is the equivalent to your Bills.java without a lot of the bloat such as FAB. :-
public class MainActivity extends AppCompatActivity {
public static final String ID_INTENTEXTRA = DBAdapter.KEY_ROWID + "_INTENTEXTRA"; //<<<< ADDED
DBAdapter mDBAdapter;
Cursor mCsr;
ListView mrecycleview;
ArrayAdapter adapter; //<<<< NOT ListAdapter
Context context; // ADDED
private static final String TAG ="assignments";
ArrayList<Bill> mBillList = new ArrayList<>();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
context = this;
mrecycleview = this.findViewById(R.id.mRecycleView);
mDBAdapter = new DBAdapter(this);
addSomeData();
adapter = new ArrayAdapter<Bill>(
this,
android.R.layout.simple_list_item_1,
mBillList
);
mrecycleview.setAdapter(adapter);
mrecycleview.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
#Override
public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
Bill b = (Bill) adapter.getItem(position);
Intent i = new Intent(context,Editbills.class);
i.putExtra(ID_INTENTEXTRA,b.getId()); //Get ID
startActivity(i);
return true;
}
});
rebuildBillList();
}
//<<<< ADDED Method to refresh the ListView resumed
#Override
protected void onResume() {
super.onResume();
rebuildBillList();
}
// Add some data (note will add 2 rows each time it is run)
private void addSomeData() {
mDBAdapter.insertRecord("Bill1","2018-10-02","English");
mDBAdapter.insertRecord("Bill2","2018-09-03","Mathematics");
mDBAdapter.insertRecord("Bill3","2018-11-04", "Geography");
}
public void rebuildBillList() {
mBillList.clear();
mCsr = mDBAdapter.getAllAsCursor();
while (mCsr.moveToNext()) {
mBillList.add(new Bill(
mCsr.getLong(mCsr.getColumnIndex(DBAdapter.KEY_ROWID)),
mCsr.getString(mCsr.getColumnIndex(DBAdapter.KEY_NAME)),
mCsr.getString(mCsr.getColumnIndex(DBAdapter.KEY_AMOUNT)),
mCsr.getString(mCsr.getColumnIndex(DBAdapter.KEY_DUEDATE))
)
);
}
adapter.notifyDataSetChanged();
}
}
Note the above adds 3 rows each time it is run.
Editbills.java
public class Editbills extends AppCompatActivity {
Button button;
private static final String Tag = "assignments";
DBAdapter db = new DBAdapter(this);
private String selectedName;
private long selectedID;
DBAdapter dbAdapter;
private EditText editText,editText2,editText3;
Context context;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_editbills);
context = this;
dbAdapter = new DBAdapter(this); //<<<< ADDED
button=(Button)findViewById(R.id.button);
editText =(EditText)findViewById(R.id.edittext);
editText2=(EditText)findViewById(R.id.edittext2);
editText3 =(EditText)findViewById(R.id.edittext3);
//get the intent extra from the ListDataActivity
Intent receivedIntent = getIntent();
//now get the itemID we passed as an extra
selectedID = receivedIntent.getLongExtra(MainActivity.ID_INTENTEXTRA,-1L); //NOTE: -1 is just the default value
populateDisplay(selectedID);
//now get the name we passed as an extra
//selectedName = receivedIntent.getStringExtra("name");
//set the text to show the current selected name
//editText.setText(selectedName); <<<< commented out
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
/*
Log.d("test", "adding");
db.open();
long id = db.insertRecord(editText.getText().toString(), editText2.getText().toString(), editText3.getText().toString());
db.close();
Toast.makeText(Editbills.this," Added", Toast.LENGTH_LONG).show();
*/
/*
* <<<< Not the way as it ends/closes the existing activity
Intent q = new Intent(getApplicationContext(),MainActivity.class);
startActivity(q);
*/
String toast = "Updated.";
if (dbAdapter.updateRecord(selectedID,
editText.getText().toString(),
editText2.getText().toString(),
editText3.getText().toString())) {
} else {
toast = "Not Updated.";
}
Toast.makeText(context,toast,Toast.LENGTH_LONG).show();
finish(); //<<<< ends/closes this activity and returns to calling activity
}
});
}
private void populateDisplay(long id) {
Cursor csr = dbAdapter.getRecordById(id);
if (csr.moveToFirst()) {
editText.setText(csr.getString(csr.getColumnIndex(DBAdapter.KEY_NAME)));
editText2.setText(csr.getString(csr.getColumnIndex(DBAdapter.KEY_AMOUNT)));
editText3.setText(csr.getString(csr.getColumnIndex(DBAdapter.KEY_DUEDATE)));
}
csr.close();
}
}
Basically as per the original answer.
DBAdapter.java
public class DBAdapter {
public static final String KEY_ROWID = "id";
public static final String KEY_NAME = "name";
public static final String KEY_AMOUNT = "amount";
public static final String KEY_DUEDATE = "duedate";
private static final String TAG = "DBAdapter";
private static final String DATABASE_NAME = "billsdb";
private static final String DATABASE_TABLE = "bills";
private static final int DATABASE_VERSION = 2;
// Replaces DATABASE_CREATE using the one source definition
private static final String TABLE_CREATE =
"CREATE TABLE IF NOT EXISTS " + DATABASE_TABLE + "(" +
KEY_ROWID + " INTEGER PRIMARY KEY, " + // AUTOINCREMENT NOT REQD
KEY_NAME + " DATE NOT NULL, " +
KEY_AMOUNT + " VARCHAR ," +
KEY_DUEDATE + " DATE " +
")";
private Context context;
private DatabaseHelper DBHelper;
private SQLiteDatabase db;
public DBAdapter(Context ctx)
{
this.context = ctx;
DBHelper = new DatabaseHelper(context);
}
private static class DatabaseHelper extends SQLiteOpenHelper
{
DatabaseHelper(Context context)
{
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db)
{
db.execSQL(TABLE_CREATE); // NO need to encapsulate in try clause
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)
{
Log.w(TAG, "Upgrading database from version " + oldVersion + " to "
+ newVersion + ", which will destroy all old data");
db.execSQL("DROP TABLE IF EXISTS contacts"); //????????
db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE);
onCreate(db);
}
}
//---opens the database--- NOT NEEDED
public DBAdapter open() throws SQLException
{
db = DBHelper.getWritableDatabase();
return this;
}
//---closes the database--- NOT NEEDED
public void close()
{
DBHelper.close();
}
//---insert a record into the database---
public long insertRecord(String name, String amount, String duedate)
{
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_NAME, name);
initialValues.put(KEY_AMOUNT, amount);
initialValues.put(KEY_DUEDATE, duedate);
return DBHelper.getWritableDatabase().insert(DATABASE_TABLE,
null,
initialValues
);
}
//---deletes a particular record---
public boolean deleteContact(long rowId)
{
return db.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0;
}
//---retrieves all the records--- SEE FOLLOWING METHOD
public Cursor getAllRecords()
{SQLiteDatabase db = DBHelper.getWritableDatabase();
String query ="SELECT * FROM " + DATABASE_TABLE;
Cursor data = db.rawQuery(query,null);
return data;
}
//As per getAllRecords but using query convenience method
public Cursor getAllAsCursor() {
return DBHelper.getWritableDatabase().query(
DATABASE_TABLE,
null,null,null,null,null,null
);
}
public Cursor getItemID(String name) {
SQLiteDatabase db = DBHelper.getWritableDatabase();
String query = "SELECT " + KEY_ROWID + " FROM " + DATABASE_TABLE +
" WHERE " + KEY_NAME + " = '" + name + "'";
Cursor data = db.rawQuery(query, null);
return data;
}
// Retrieve a row (single) according to id
public Cursor getRecordById(long id) {
return DBHelper.getWritableDatabase().query(
DATABASE_TABLE,
null,
KEY_ROWID + "=?",
new String[]{String.valueOf(id)},
null,null,null
);
}
//---updates a record---
public boolean updateRecord(long rowId, String name, String amount, String duedate) {
ContentValues args = new ContentValues();
args.put(KEY_NAME, name);
args.put(KEY_AMOUNT, amount);
args.put(KEY_DUEDATE, duedate);
String whereclause = KEY_ROWID + "=?";
String[] whereargs = new String[]{String.valueOf(rowId)};
return DBHelper.getWritableDatabase().update(DATABASE_TABLE,
args,
whereclause,
whereargs
) > 0;
}
}
Basically as was except that upDateRecord has been un-commented, again as per the original answer.
Results
1st Run - MainActivity (Bills) :-
Long Click Bill2 (note changed from Click as Long Click is less prone to accidental use)
Change data (Update button not clicked)
Update Button Clicked (Toast was Updated.)
Note use of finish() to return to the invoking activity and then the use of onResume to refresh the list according to the updated data (possibly your next question).
using startActivity will simply result in issues.
Note Values are date and course rather then amount and duedate because I didn't change the values in the addSomeData method (easily done).
the actual data itself is irrelevant to the process.

Android Studio project

Hi i am doing an andorid studio project, when I am adding my data the application and then trying to view the data im getting an Error saying "Error, Nothing Found". I made up a SQLite Database and hope someone can help me find the error.
package ie.wit.andrew.drivingschool;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class DatabaseHelper extends SQLiteOpenHelper {
public static final String DATABASE_NAME = "Driver.db";
public static final String TABLE_NAME = "driver_table";
public static final String COL_1 = "ID";
public static final String COL_2 = "NAME";
public static final String COL_3 = "DATE OF BIRTH";
public static final String COL_4 = "LOGBOOK NUMBER"; //Making up my
//database of the
//information I will
//be entering into my
//application
public static final String COL_5 = "LESSON NUMBER";
public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, 1); //when this constructor is
//called your Database has been
//created
}
#Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("create table " + TABLE_NAME + " (ID INTEGER PRIMARY KEY
AUTOINCREMENT,NAME TEXT,DATE OF BIRTH TEXT, LOGBOOK NUMBER TEXT, LESSON
NUMBER INTEGER)");
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS "+TABLE_NAME);
onCreate(db);
}
public boolean insertData(String name, String dateofbirth, String
logbooknumber, String lessonnumber) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put(COL_2,name);
contentValues.put(COL_3,dateofbirth);
contentValues.put(COL_4,logbooknumber);
contentValues.put(COL_5,lessonnumber);
long result = db.insert(TABLE_NAME,null,contentValues); //This method
//returns -1
if (result == -1)
return false;
else
return true;
}
public Cursor getAllData() {
SQLiteDatabase db = this.getWritableDatabase();
Cursor res = db.rawQuery("select * from "+ TABLE_NAME,null);
return res;
}
}
package ie.wit.andrew.drivingschool;
import android.database.Cursor;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class DrivingSchool extends AppCompatActivity {
DatabaseHelper myDb;
EditText editName,editDateofBirth,editLogbookNumber,editLessonNumber;
Button btnAddData;
Button btnviewAll;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_driving_school);
myDb = new DatabaseHelper(this);
editName = (EditText)findViewById(R.id.editText_name);
editDateofBirth = (EditText)findViewById(R.id.editText_dateofbirth);
editLogbookNumber = (EditText)findViewById(R.id.editText_logbooknumber);
editLessonNumber = (EditText)findViewById(R.id.editText_lessonNumber);
btnAddData = (Button)findViewById(R.id.button_add);
btnviewAll = (Button)findViewById(R.id.button_viewAll);
AddData();
viewAll();
}
public void AddData() {
btnAddData.setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View v) {
boolean isInserted =
myDb.insertData(editName.getText().toString(),
editDateofBirth.getText().toString(),
editLogbookNumber.getText().toString(),
editLessonNumber.getText().toString());
if(isInserted = true)
Toast.makeText(DrivingSchool.this,"Data
Inserted",Toast.LENGTH_LONG).show();
else
Toast.makeText(DrivingSchool.this,"Data not
Inserted", Toast.LENGTH_LONG).show();
}
}
);
}
public void viewAll() {
btnviewAll.setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View v){
Cursor res = myDb.getAllData();
if(res.getCount() == 0) {
//Show Message
showMessage("Error", "Nothing found");
return;
}
StringBuffer buffer = new StringBuffer();
while(res.moveToNext()) {
buffer.append("ID : "+ res.getString(0)+"\n");
buffer.append("NAME : "+ res.getString(1)+"\n");
buffer.append("DATE OF BIRTH : "+
res.getString(2)+"\n");
buffer.append("LOGBOOK NUMBER : "+
res.getString(3)+"\n\n");;
}
//showdata
showMessage("Data",buffer.toString());
}
}
);
}
public void showMessage(String title,String Message){
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setCancelable(true);
builder.setTitle(title);
builder.setMessage(Message);
builder.show();
}
}

Try removing space from your column name's

you are providing wrong column name that's why your database is not creating, please check this link for complete guide for creating and using database in Android application
http://www.androidhive.info/2011/11/android-sqlite-database-tutorial/

Android app stalls when implementing SQLite database

At first the app would just crash when I started it with an emulator, Not sure what I changed to get it to run but now it will run the onCreate method however, when I implement the addButtonClicked method the app just stalls and the Android Monitor displays "Suspending all threads" every few seconds and I'm not sure where to even begin debugging. Any pointers in the right direction would be greatly appreciated as I'm fairly new to Android development.
MainActivity.java
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
EditText testInput;
TextView testText;
MyDBHandler dbHandler;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
testInput = (EditText) findViewById(R.id.testInput);
testText = (TextView) findViewById(R.id.testText);
dbHandler = new MyDBHandler(this, null, null, 1);
printDatabase();
}
//Add product to database
public void addButtonClicked(View view){
Products product = new Products((testInput.getText().toString()));
dbHandler.addProduct(product);
printDatabase();
}
// Delete Items
public void deleteButtonClicked(View view){
String inputText = testText.getText().toString();
dbHandler.deleteProduct(inputText);
printDatabase();
}
public void printDatabase(){
String dbString = dbHandler.databaseToString();
testText.setText(dbString);
testInput.setText("");
}
}
Products.java
public class Products {
private int _id;
private String _productname;
public Products(){
}
public Products(String productname) {
this._productname = productname;
}
public void set_id(int _id) {
this._id = _id;
}
public void set_productname(String _productname) {
this._productname = _productname;
}
public int get_id() {
return _id;
}
public String get_productname() {
return _productname;
}
}
MyDBHandler.java
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.Cursor;
import android.content.Context;
import android.content.ContentValues;
public class MyDBHandler extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 15;
private static final String DATABASE_NAME = "products.db";
public static final String TABLE_PRODUCTS = "products";
public static final String COLUMN_ID = "_id";
public static final String COLUMN_PRODUCTNAME = "productname";
public MyDBHandler(Context context, String name, SQLiteDatabase.CursorFactory factory, int version) {
super(context, DATABASE_NAME, factory, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db) {
String query = "CREATE TABLE " + TABLE_PRODUCTS +"(" +
COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT ," +
COLUMN_PRODUCTNAME +" TEXT " +
");";
db.execSQL(query);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE_PRODUCTS);
onCreate(db);
}
//Add new row to the database
public void addProduct(Products product){
ContentValues values = new ContentValues();
values.put(COLUMN_PRODUCTNAME, product.get_productname());
SQLiteDatabase db = getWritableDatabase();
db.insert(TABLE_PRODUCTS, null, values);
db.close();
}
//Delete product from database
public void deleteProduct(String productName){
SQLiteDatabase db = getWritableDatabase();
db.execSQL("DELETE FROM " + TABLE_PRODUCTS + " WHERE " + COLUMN_PRODUCTNAME + "=\"" + productName + "\";" );
}
//Print of DB as sting
public String databaseToString(){
String dbString = "";
SQLiteDatabase db = getWritableDatabase();
String query = "SELECT * FROM " + TABLE_PRODUCTS + " WHERE 1";
//Cursor point to a location in your results
Cursor c = db.rawQuery(query, null);
//Move to the first row in your results
c.moveToFirst();
while (!c.isAfterLast()){
if(c.getString(c.getColumnIndex("productname"))!= null){
dbString += c.getString(c.getColumnIndex("productname"));
dbString += "\n";
}
}
db.close();
return dbString;
}
}

for your databaseToString method you are performing a retrieve operation. You should be doing a read operation in a thread other than UI thread. Try fetching in AsyncTask. It should work. Implementation for your databaseToString should be handled by AsyncTask.
Happy Coding..

We Keep Coding

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setAdapter() crashes android app in android studio - java

You can simply change RecyclerView to ListView. Or if you want to use RecyclerView, you have to create a custom Recyclerview Adapter. Here a Beginner friendly Guide: https://medium.com/#suhanshupatel/recyclerview-in-android-for-beginner-cfbc132a0dec

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Android app stalls when implementing SQLite database

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