I have a big problem when trying to login on my android screen. I have two fields that requires user to enter email and password, it should then go and check sqlite db if correct they will be navigated to mainscreen(login success) if incorrect they will be notified via toast message. My problem is when i hit login button my app displays “Unfortunately stopped working” I cant see any errors in my code! Please someone help!!My code is posted below
*LoginActivity
package com.example.finalproject;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class LoginActivity extends Activity implements OnClickListener {
Button mLogin;
Button mNewUser;
Button mShowAll;
EditText mUsername;
EditText mPassword;
SQLiteAdapter mydb = null;
private String uname;
private String pass;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
mNewUser = (Button)findViewById(R.id.buttonNewUser);
mNewUser.setOnClickListener(this);
mLogin = (Button)findViewById(R.id.buttonLogin);
mLogin.setOnClickListener(this);
mShowAll = (Button)findViewById(R.id.buttonShowAll);
mShowAll.setOnClickListener(this);
}
public void onClick(View v) {
SQLiteDatabase db = new SQLiteAdapter(LoginActivity.this).openToWrite();
if (v.getId() == R.id.buttonLogin) {
mUsername = (EditText)findViewById(R.id.Username);
mPassword = (EditText)findViewById(R.id.Password);
String uname = mUsername.getText().toString();
String pass = mPassword.getText().toString();
if(uname.equals("") || uname == null){
Toast.makeText(getApplicationContext(), "Username Empty",
Toast.LENGTH_SHORT).show();
}
else if(pass.equals("") || pass == null){
Toast.makeText(getApplicationContext(), "Password Empty",
Toast.LENGTH_SHORT).show();
}
}
Cursor c = db.rawQuery("SELECT email FROM MY_USERS_TABLE WHERE email= ? AND password=?", new String[] {uname, pass});
if(c.moveToFirst()) {
Toast.makeText(getApplicationContext(), "Success", Toast.LENGTH_SHORT).show();
Intent main = new Intent(LoginActivity.this, MainMenuActivity.class);
startActivity(main);
}
else {
Toast.makeText(getApplicationContext(), "Failed..\nTry Again", Toast.LENGTH_SHORT).show();
}
}
}
SQLIteAdapter
package com.example.finalproject;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.widget.Toast;
public class SQLiteAdapter {
public static final String MYDATABASE_NAME = "MY_DEVELOPMENT_PROJECT_DATABASE";
public static final String MYDATABASE_TABLE = "MY_USERS_TABLE";
public static final int MYDATABASE_VERSION = 1;
public static final String KEY_ID = "_id";
public static final String KEY_NAME = "name";
public static final String KEY_EMAIL = "email";
public static final String KEY_PASSWORD = "password";
private static final String SCRIPT_CREATE_DATABASE =
"create table " + MYDATABASE_TABLE + " ("
+ KEY_ID + " integer primary key autoincrement, "
+ KEY_NAME + " text not null, "
+ KEY_EMAIL + " text not null, "
+ KEY_PASSWORD + " text not null);";
private SQLiteHelper sqLiteHelper;
private SQLiteDatabase sqLiteDatabase;
private Context context;
public SQLiteAdapter(Context c){
context = c;
}
public SQLiteAdapter(SQLiteAdapter sqLiteAdapter) {
// TODO Auto-generated constructor stub
}
public SQLiteDatabase openToRead() throws android.database.SQLException {
sqLiteHelper = new SQLiteHelper(context, MYDATABASE_NAME, null, MYDATABASE_VERSION);
sqLiteDatabase = sqLiteHelper.getReadableDatabase();
return sqLiteDatabase;
}
public SQLiteDatabase openToWrite() throws android.database.SQLException {
sqLiteHelper = new SQLiteHelper(context, MYDATABASE_NAME, null,
MYDATABASE_VERSION);
sqLiteDatabase = sqLiteHelper.getWritableDatabase();
return sqLiteDatabase;
}
/*public SQLiteAdapter openToWrite() throws android.database.SQLException {
sqLiteHelper = new SQLiteHelper(context, MYDATABASE_NAME, null, MYDATABASE_VERSION);
sqLiteDatabase = sqLiteHelper.getWritableDatabase();
return this;
}*/
public void close(){
sqLiteHelper.close();
}
public long insert(String name, String email, String password){
ContentValues contentValues = new ContentValues();
contentValues.put(KEY_NAME, name);
contentValues.put(KEY_EMAIL, email);
contentValues.put(KEY_PASSWORD, password);
return sqLiteDatabase.insert(MYDATABASE_TABLE, null, contentValues);
}
public int deleteAll(){
return sqLiteDatabase.delete(MYDATABASE_TABLE, null, null);
}
public Cursor queueAll(){
String[] columns = new String[]{KEY_ID, KEY_NAME, KEY_EMAIL,KEY_PASSWORD};
Cursor cursor = sqLiteDatabase.query(MYDATABASE_TABLE, columns,
null, null, null, null, null);
return cursor;
}
public class SQLiteHelper extends SQLiteOpenHelper {
public SQLiteHelper(Context context, String name,
CursorFactory factory, int version) {
super(context, name, factory, version);
}
@Override
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
db.execSQL(SCRIPT_CREATE_DATABASE);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// TODO Auto-generated method stub
}
}
}
RegisteActivty
package com.example.finalproject;
import android.app.Activity;
import android.content.Intent;
import android.database.Cursor;
import android.os.Bundle;
import android.view.View;
//import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;
import android.widget.TextView;
import android.widget.Toast;
public class RegisterActivity extends Activity {
EditText inputName, inputEmail, inputPassword;
Button buttonRegister, buttonDeleteAll;
TextView login;
private SQLiteAdapter mySQLiteAdapter;
ListView listContent;
SimpleCursorAdapter cursorAdapter;
Cursor cursor;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.register_activity);
inputName = (EditText)findViewById(R.id.name);
inputEmail = (EditText)findViewById(R.id.email);
inputPassword = (EditText)findViewById(R.id.password);
buttonRegister = (Button)findViewById(R.id.register);
//buttonDeleteAll = (Button)findViewById(R.id.showAll);
listContent = (ListView)findViewById(R.id.contentlist);
mySQLiteAdapter = new SQLiteAdapter(this);
mySQLiteAdapter.openToWrite();
cursor = mySQLiteAdapter.queueAll();
// String[] from = new String[]{SQLiteAdapter.KEY_ID, SQLiteAdapter.KEY_NAME, SQLiteAdapter.KEY_EMAIL,SQLiteAdapter.KEY_PASSWORD};
/*int[] to = new int[]{R.id.id, R.id.text1, R.id.text2,R.id.text3};
cursorAdapter =
new SimpleCursorAdapter(this, R.layout.row, cursor, from, to);
listContent.setAdapter(cursorAdapter);*/
buttonRegister.setOnClickListener(buttonAddOnClickListener);
//buttonShowAll.setOnClickListener(buttonShowAllOnClickListener);
//addListenerOnRegButton();
TextView loginScreen = (TextView) findViewById(R.id.login);
// Listening to login
loginScreen.setOnClickListener(TextLoginOnClickListener);
}
TextView.OnClickListener TextLoginOnClickListener
= new TextView.OnClickListener(){
@Override
public void onClick(View arg0) {
Intent i = new Intent(getApplicationContext(), LoginActivity.class);
startActivity(i);
}
};
Button.OnClickListener buttonAddOnClickListener
= new Button.OnClickListener(){
@Override
public void onClick(View arg0) {
String data1 = inputName.getText().toString();
String data2 = inputEmail.getText().toString();
String data3 = inputPassword.getText().toString();
boolean invalid = false;
if(data1.equals("")){
invalid = true;
Toast.makeText(getApplicationContext(), "Name Missing", Toast.LENGTH_SHORT).show();
}else if(data2.equals("")){
invalid = true;
Toast.makeText(getApplicationContext(), "Email ID Missing", Toast.LENGTH_SHORT).show();
}else if(data3.equals("")){
invalid = true;
Toast.makeText(getApplicationContext(), "Password Missing", Toast.LENGTH_SHORT).show();
}
if(invalid == false){
mySQLiteAdapter.insert(data1, data2, data3);
updateList();
Toast.makeText(RegisterActivity.this, "You are now registered",
Toast.LENGTH_SHORT).show();
Intent i_register = new Intent(RegisterActivity.this, LoginActivity.class);
startActivity(i_register);
inputName.setText("");
inputEmail.setText("");
inputPassword.setText("");
finish();
}
}
};
/*Button.OnClickListener buttonShowAllOnClickListener1
= new Button.OnClickListener(){
@Override
public void onClick(View arg0) {
Intent i = new Intent(RegisterActivity.this, MainMenuActivity.class);
startActivity(i);
finish();
}
};
@Override
protected void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
mySQLiteAdapter.close();
}*/
private void updateList(){
//cursor.requery();
}
}
LogCat
02-04 02:55:56.085: E/AndroidRuntime(17402): FATAL EXCEPTION: main
02-04 02:55:56.085: E/AndroidRuntime(17402): java.lang.IllegalArgumentException: the bind value at index 2 is null
02-04 02:55:56.085: E/AndroidRuntime(17402): at android.database.sqlite.SQLiteProgram.bindString(SQLiteProgram.java:164)
02-04 02:55:56.085: E/AndroidRuntime(17402): at android.database.sqlite.SQLiteProgram.bindAllArgsAsStrings(SQLiteProgram.java:200)
02-04 02:55:56.085: E/AndroidRuntime(17402): at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:47)
02-04 02:55:56.085: E/AndroidRuntime(17402): at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1314)
02-04 02:55:56.085: E/AndroidRuntime(17402): at android.database.sqlite.SQLiteDatabase.rawQuery(SQLiteDatabase.java:1253)
02-04 02:55:56.085: E/AndroidRuntime(17402): at com.example.finalproject.LoginActivity.onClick(LoginActivity.java:62)
02-04 02:55:56.085: E/AndroidRuntime(17402): at android.view.View.performClick(View.java:4202)
02-04 02:55:56.085: E/AndroidRuntime(17402): at android.view.View$PerformClick.run(View.java:17340)
02-04 02:55:56.085: E/AndroidRuntime(17402): at android.os.Handler.handleCallback(Handler.java:725)
02-04 02:55:56.085: E/AndroidRuntime(17402): at android.os.Handler.dispatchMessage(Handler.java:92)
02-04 02:55:56.085: E/AndroidRuntime(17402): at android.os.Looper.loop(Looper.java:137)
02-04 02:55:56.085: E/AndroidRuntime(17402): at android.app.ActivityThread.main(ActivityThread.java:5039)
02-04 02:55:56.085: E/AndroidRuntime(17402): at java.lang.reflect.Method.invokeNative(Native Method)
02-04 02:55:56.085: E/AndroidRuntime(17402): at java.lang.reflect.Method.invoke(Method.java:511)
02-04 02:55:56.085: E/AndroidRuntime(17402): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
02-04 02:55:56.085: E/AndroidRuntime(17402): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
02-04 02:55:56.085: E/AndroidRuntime(17402): at dalvik.system.NativeStart.main(Native Method)
02-04 02:55:56.555: D/dalvikvm(17402): GC_CONCURRENT freed 261K, 11% free 3060K/3436K, paused 126ms+33ms, total 459ms
02-04 03:00:56.444: I/Process(17402): Sending signal. PID: 17402 SIG: 9
Your problem comes in this line:
db.rawQuery("SELECT email FROM MY_USERS_TABLE WHERE email= ? AND password=?", new String[] {uname, pass})What’s happening is that even if your
ifstatement outputs a Toast to say that the edittexts are empty, this section gets executed, sounameandpassare null, which is giving you theIllegalArgumentException: the bind value at index 2 is nullerror, as you’re passing the SQL function null values.Simple fix: only execute the bottom section of code if the values aren’t null or empty: