I am new to android I am creating an android application that consists of a registration dialog and sqlite storage.But here i was getting null pointer exception.I didn't find any mistake but it was showing null pointer exception.I have been trying this code since 2 hours
Here i used custom buttons fin alert dialog downloaded from here This is my activity displays alert dialog and registers into database
package com.developer.milanandroid;
import java.io.File;
import java.util.ArrayList;
import com.milan.lib.progressgenarator.lib.ProgressGenerator;
import com.milan.lib.progressgenarator.lib.ProgressGenerator.OnCompleteListener;
import com.milan.paperbuttons.adminsettingsbuttons;
import com.milan.paperbuttons.ShowDatabase;
import com.milan.validation.lib.RegExpressionValueValidator;
import com.milan.validation.lib.ValidationManager;
import com.processbutton.lib.milan.ActionProcessButton;
import android.app.Activity;
import android.app.Dialog;
import android.content.Intent;
import android.database.Cursor;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.text.method.HideReturnsTransformationMethod;
import android.text.method.PasswordTransformationMethod;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.Window;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.TextView;
import android.widget.Toast;
import android.widget.CompoundButton.OnCheckedChangeListener;
public class AdminSettings extends Activity implements OnCompleteListener{
public LoginDataBaseAdapter logindatabase_adapter_child;
// public SQLiteDatabase db;
Button Review;
TextView text_fetched_database_results;
String username,password;
Cursor c;
adminsettingsbuttons review,fetch_database,adduser;
MediaPlayer media_player;
private ArrayList<String> USER_NAME = new ArrayList<String>();
private ArrayList<String> USER_PWD = new ArrayList<String>();
Dialog database_list;
DataBaseHelper database_helper_child;
File Milan,Sample;
//-----------------------RegistrationDialog variables--------------------------------//
com.milan.material.widgets.dialog.FloatingEditText username_dialog,password_dialog,confirm_password;
Dialog registration_dialog;
private ValidationManager validation_manager;
CheckBox show_password;
public ActionProcessButton Registerbutton,clear_Button;
LoginDataBaseAdapter logindatabaseadapter;
String dialog_user_name_string,dialog_pasword_string,dialog_confirm_string;
int username_length=5,password_length=5;
String stored_pass;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.admin_settings);
fetch_database = (adminsettingsbuttons)findViewById(R.id.Button_Fetch_from_Database);
fetch_database.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent database_list = new Intent(AdminSettings.this,DatabaseListView.class);
startActivity(database_list);
}
});
review = (adminsettingsbuttons)findViewById(R.id.button_review);
review.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//String extStorageDirectory = Environment.getExternalStorageDirectory().toString();
//Milan = new File(extStorageDirectory+"/Milan");
//if(!Milan.exists()){
// Milan.mkdir();
/*media_player = new MediaPlayer(AdminSettings.this,)
media_player.start();*/
//}
//Sample = new File(extStorageDirectory+"/Milan/Sample.txt");
// try {
// Sample.createNewFile();
// } catch (IOException e) {
// TODO Auto-generated catch block
// e.printStackTrace();
// }
Intent review = new Intent(getApplicationContext(),Review.class);
startActivity(review);
}
});
adduser= (adminsettingsbuttons)findViewById(R.id.button_Adduser);
adduser.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
registration_dialog = new Dialog(AdminSettings.this);
registration_dialog.requestWindowFeature(Window.FEATURE_LEFT_ICON);
registration_dialog.setContentView(R.layout.registrationdialog);
registration_dialog.setTitle("User Registration");
registration_dialog.setFeatureDrawableResource(Window.FEATURE_LEFT_ICON, R.drawable.user);
username_dialog = (com.milan.material.widgets.dialog.FloatingEditText)registration_dialog.findViewById(R.id.edt_dialog_username);
password_dialog = (com.milan.material.widgets.dialog.FloatingEditText)registration_dialog.findViewById(R.id.edt_dialog_password);
confirm_password = (com.milan.material.widgets.dialog.FloatingEditText)registration_dialog.findViewById(R.id.edt_dialog_confirm_password);
validation_manager = new ValidationManager(AdminSettings.this);
/*-----------------For validating each username and password fields in the registration dialog----------------------*/
validation_manager.add("", new RegExpressionValueValidator(username_dialog, "^[a-zA-Z0-9\\-'\\s]{3,}$", "Please enter your user name"));
validation_manager.add("", new RegExpressionValueValidator(password_dialog, "^[a-zA-Z0-9\\-'\\s]{3,}$", "Please enter your password"));
validation_manager.add("", new RegExpressionValueValidator(confirm_password, "^[a-zA-Z0-9\\-'\\s]{3,}$","Please enter confirm password"));
/*-------------------For viewing passwords on clicking show passwords checkbox-------------------------------------------*/
show_password = (CheckBox)registration_dialog.findViewById(R.id.show_password);
show_password.setOnCheckedChangeListener(new OnCheckedChangeListener()
{
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if(!isChecked)
{
password_dialog.setTransformationMethod(PasswordTransformationMethod.getInstance());
confirm_password.setTransformationMethod(PasswordTransformationMethod.getInstance());
}
else
{
password_dialog.setTransformationMethod(HideReturnsTransformationMethod.getInstance());
confirm_password.setTransformationMethod(HideReturnsTransformationMethod.getInstance());
}
}
});
/*-----------------------Progress generator of register button------------------------------------*/
final ProgressGenerator progressGenerator = new ProgressGenerator(AdminSettings.this);
Registerbutton = (ActionProcessButton)registration_dialog.findViewById(R.id.Btn_Register);
Registerbutton.setMode(ActionProcessButton.Mode.ENDLESS);
Registerbutton.setOnClickListener(new View.OnClickListener()
{
@Override
public void onClick(View v)
{
int a,b,c;
dialog_user_name_string = username_dialog.getText().toString();
dialog_pasword_string = password_dialog.getText().toString();
dialog_confirm_string = confirm_password.getText().toString();
//dialog_seq_answer = seq_answer.getText().toString();
if((!dialog_user_name_string.equals("")) &&(!dialog_pasword_string.equals("")) && (!dialog_confirm_string.equals(""))){
a= dialog_user_name_string.length();
b= dialog_pasword_string.length();
c= dialog_confirm_string.length();
if((a<=username_length) && (b<=password_length) && (c<=password_length)){
Toast.makeText(AdminSettings.this, "Sorry,Username and password length must be greater than 5 characters", Toast.LENGTH_LONG).show();
media_player = MediaPlayer.create(AdminSettings.this, R.raw.usernameandpasswordlength);
media_player.start();
}
else{
stored_pass = logindatabaseadapter.checkSinlgeEntry(dialog_user_name_string);
if(!stored_pass.equals("NOT EXIST")){
if(dialog_pasword_string.equals(dialog_confirm_string)){
logindatabaseadapter.insertEntry(dialog_user_name_string, dialog_pasword_string); //Inserting username and password into the database
progressGenerator.start(Registerbutton);
Registerbutton.setEnabled(false);
media_player= MediaPlayer.create(AdminSettings.this, R.raw.regesteringintodatabase);
media_player.start();
username_dialog.setEnabled(false);
password_dialog.setEnabled(false);
confirm_password.setEnabled(false);
//registration_dialog.setCancelable(false);
}
else{
media_player= MediaPlayer.create(AdminSettings.this, R.raw.databasepasswordsnotmatched);
media_player.start();
Toast.makeText(AdminSettings.this, "Passwords did not matched please try again", Toast.LENGTH_LONG).show();
}
}
}
}
else {
/*------------------Calling for validation---------------------------*/
validation_manager.validateAllAndSetError();
Toast.makeText(AdminSettings.this, "please fill all the fields", Toast.LENGTH_LONG).show();
media_player= MediaPlayer.create(AdminSettings.this, R.raw.pleasefilallthedetails);
media_player.start();
}
}
});
clear_Button = (ActionProcessButton)registration_dialog.findViewById(R.id.Btn_Clear);
clear_Button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
username_dialog.setText("");
password_dialog.setText("");
confirm_password.setText("");
}
});
registration_dialog.show();
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.admin_settings, 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();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
public void onComplete() {
Toast.makeText(AdminSettings.this, "Account created succesfully"+" "+dialog_user_name_string,Toast.LENGTH_LONG).show();
media_player= MediaPlayer.create(AdminSettings.this, R.raw.congratulationsdb);
media_player.start();
}
}
Logindatabase Adapter:
package com.developer.milanandroid;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.view.View;
public class LoginDataBaseAdapter
{
//Database name
static final String DATABASE_NAME = "MilanloginRegistration.db";
static final int DATABASE_VERSION = 1;
public static final int NAME_COLUMN = 1;
// TODO: Create public field for each column in your table.
// SQL Statement to create a new database.
public static final String TABLE_NAME="MilanLoginregistration";
public static final String ID="_id";
public static final String USER_NAME="USERNAME";
public static final String USER_PASSWORD ="PASSWORD";
static final String DATABASE_CREATE = "create table "+ TABLE_NAME +
"( " +ID+" integer primary key autoincrement,"+"USERNAME text not null,"+USER_PASSWORD+" text not null); ";
// Variable to hold the database instance
public SQLiteDatabase db;
// Context of the application using the database.
private final Context context;
// Database open/upgrade helper
private DataBaseHelper dbHelper;
public LoginDataBaseAdapter(Context _context)
{
context = _context;
dbHelper = new DataBaseHelper(context, DATABASE_NAME, null, DATABASE_VERSION);
}
public LoginDataBaseAdapter open() throws SQLException
{
db = dbHelper.getWritableDatabase();
return this;
}
public void close()
{
db.close();
}
public SQLiteDatabase getDatabaseInstance()
{
return db;
}
public LoginDataBaseAdapter opentoRead() throws android.database.SQLException{
dbHelper = new DataBaseHelper(context, DATABASE_NAME, null, DATABASE_VERSION);
db = dbHelper.getReadableDatabase();
return this;
}
public LoginDataBaseAdapter opentoWrite() throws android.database.SQLException{
dbHelper = new DataBaseHelper(context, DATABASE_NAME, null, DATABASE_VERSION);
db = dbHelper.getWritableDatabase();
return this;
}
public void Close(){
dbHelper.close();
}
public void insertEntry(String username,String password)
{
ContentValues newValues = new ContentValues();
newValues.put("USERNAME",username);
newValues.put("PASSWORD",password);
// Insert the row into your table
db.insert("MilanLoginregistration",null,newValues);
///Toast.makeText(context, "Reminder Is Successfully Saved", Toast.LENGTH_LONG).show();
}
public int deleteAll(){
return db.delete(TABLE_NAME, null, null);
}
public void deleteEntry(int id){
//String id=String.valueOf(ID);
db.delete(TABLE_NAME, ID+"="+id, null);
// Toast.makeText(context, "Number fo Entry Deleted Successfully : "+numberOFEntriesDeleted, Toast.LENGTH_LONG).show();
}
public Cursor queue_all(){
String[] columns = new String[]{ID,"USERNAME","PASSWORD"};
Cursor cursor_queue_all =db.query(TABLE_NAME, columns, null, null, null, null, null);
return cursor_queue_all;
}
public Cursor feching_Data(){
String[] columns = {ID,USER_NAME,USER_PASSWORD};
db = dbHelper.getWritableDatabase();
Cursor cursor = db.query(TABLE_NAME, columns,null,null,null,null,null);
return cursor;
}
public String getSinlgeEntry(String userName)
{
Cursor cursor=db.query("MilanLoginregistration", null, " USERNAME=?", new String[]{userName}, null, null, null);
if(cursor.getCount()<1) // UserName Not Exist
{
cursor.close();
return "NOT EXIST";
}
cursor.moveToFirst();
String password= cursor.getString(cursor.getColumnIndex("PASSWORD"));
//cursor.close();
return password;
}
public String checkSinlgeEntry(String userName)
{
Cursor cursor=db.query("MilanLoginregistration", null, " USERNAME=?", new String[]{userName}, null, null, null);
if(cursor.getCount()>=1) // UserName Exist
{
cursor.close();
return "EXIST";
}
// cursor.close();
return "";
}
public void updateEntry(String user_name,String pasword)
{
// Define the updated row content.
ContentValues updatedValues = new ContentValues();
// Assign values for each row.
updatedValues.put("USERNAME", user_name);
updatedValues.put("PASSWORD",pasword);
String where="USERNAME = ?";
db.update("MilanLoginregistration",updatedValues, where, new String[]{user_name});
}
/*public void Display(View v){
Cursor c = db.rawQuery("select * from MilanloginRegistration", null);
admin_settings_child.text_fetched_database_results.setText("");
c.moveToFirst();
do{
String username = c.getString(c.getColumnIndex("USERNAME"));
String password = c.getString(1);
admin_settings_child.text_fetched_database_results.append("USERNAME::-->"+username+"PASSWORD::-->"+password+"\n");
}while(c.moveToNext());
}*/
}
This is my logcat
01-02 05:05:03.100: E/AndroidRuntime(18345): FATAL EXCEPTION: main
01-02 05:05:03.100: E/AndroidRuntime(18345): Process: com.developer.milanandroid, PID: 18345
01-02 05:05:03.100: E/AndroidRuntime(18345): java.lang.NullPointerException
01-02 05:05:03.100: E/AndroidRuntime(18345): at com.developer.milanandroid.AdminSettings$3$2.onClick(AdminSettings.java:187)
01-02 05:05:03.100: E/AndroidRuntime(18345): at android.view.View.performClick(View.java:4438)
01-02 05:05:03.100: E/AndroidRuntime(18345): at android.view.View$PerformClick.run(View.java:18422)
01-02 05:05:03.100: E/AndroidRuntime(18345): at android.os.Handler.handleCallback(Handler.java:733)
01-02 05:05:03.100: E/AndroidRuntime(18345): at android.os.Handler.dispatchMessage(Handler.java:95)
01-02 05:05:03.100: E/AndroidRuntime(18345): at android.os.Looper.loop(Looper.java:136)
01-02 05:05:03.100: E/AndroidRuntime(18345): at android.app.ActivityThread.main(ActivityThread.java:5017)
01-02 05:05:03.100: E/AndroidRuntime(18345): at java.lang.reflect.Method.invokeNative(Native Method)
01-02 05:05:03.100: E/AndroidRuntime(18345): at java.lang.reflect.Method.invoke(Method.java:515)
01-02 05:05:03.100: E/AndroidRuntime(18345): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
01-02 05:05:03.100: E/AndroidRuntime(18345): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
01-02 05:05:03.100: E/AndroidRuntime(18345): at dalvik.system.NativeStart.main(Native Method)
You haven't defined the logindatabaseadapter variable.
When you call logindatabaseadapter.checkSinlgeEntry(...) you will get a NullPointerException as at that point, logindatabaseadapter = null.
You will need to add logindatabaseadapter = new LoginDataBaseAdapter(this) to your onCreate