Question

我正在使用Sqlite创建登录注册但无法登录。虽然注册正在运行。请帮帮我，问题出在哪里？注册工作正常，但无法单击“登录”。

MainActivity

import android.app.Activity;
import android.app.Dialog;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends Activity {
    EditText editTextUserName, editTextPassword;
    Button btnSignIn, btnSignUp;
    // String userName,password;
    LoginDataBaseAdapter loginDataBaseAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

// create a instance of SQLite Database
        loginDataBaseAdapter = new LoginDataBaseAdapter(this);
        loginDataBaseAdapter = loginDataBaseAdapter.open();
        btnSignIn = (Button) findViewById(R.id.buttonSignIn);
        btnSignUp = (Button) findViewById(R.id.buttonSignUp);
// Get The Refference Of Buttons

// Set OnClick Listener on SignUp button
        btnSignUp.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
// TODO Auto-generated method stub

/// Create Intent for SignUpActivity abd Start The Activity
                Intent intentSignUP = new Intent(getApplicationContext(), SignupActivity.class);
                startActivity(intentSignUP);
            }
        });

    }

    // Methos to handleClick Event of Sign In Button
    public void SignIn(View V)
    {
        final Dialog dialog = new Dialog(MainActivity.this);
        dialog.setContentView(R.layout.signin);
        dialog.setTitle("Login");

// get the Refferences of views
        final EditText editTextUserName=(EditText)dialog.findViewById(R.id.editTextUserNameToLogin);
        final EditText editTextPassword=(EditText)dialog.findViewById(R.id.editTextPasswordToLogin);

        Button btnSignIn=(Button)dialog.findViewById(R.id.buttonSignIn);

// Set On ClickListener
        btnSignIn.setOnClickListener(new View.OnClickListener() {

            public void onClick(View v) {
// get The User name and Password
                String userName=editTextUserName.getText().toString();
                String password=editTextPassword.getText().toString();

// fetch the Password form database for respective user name
                String storedPassword=loginDataBaseAdapter.getSinlgeEntry(userName);

// check if the Stored password matches with Password entered by user
                if(password.equals(storedPassword))
                {
                    Toast.makeText(MainActivity.this, "Congrats: Login Successfull", Toast.LENGTH_LONG).show();
                    dialog.dismiss();
                }
                else
                {
                    Toast.makeText(MainActivity.this, "User Name or Password does not match", Toast.LENGTH_LONG).show();
                }
            }
        });

        dialog.show();
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
// Close The Database
        loginDataBaseAdapter.close();
    }
}

activity_main

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <TextView
        android:id="@+id/Mobileno"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="60dp"
        android:layout_gravity="center"
        android:textSize="20dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:text="@string/Registeresd_Mobile_Number"/>

    <EditText
        android:id="@+id/editTextUserName"
        android:hint="User Name"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:textSize="15dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content">
    </EditText>

    <View
        android:layout_width="300dp"
        android:layout_height="2dp"
        android:layout_marginTop="20dp"
        android:layout_marginLeft="15dp"
        android:layout_marginRight="15dp"
        android:layout_gravity="center"
        android:background="#c0c0c0"></View>

    <TextView
        android:id="@+id/editTextPassword"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:textSize="20dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:text="@string/password"/>

    <EditText
        android:id="@+id/editTextPasswordToLogin"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_gravity="center"
        android:maxLength="20"
        android:inputType="textPassword"
        android:hint="Password" />

    <View
        android:layout_width="300dp"
        android:layout_height="2dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:background="#c0c0c0"></View>

    <Button
        android:id="@+id/buttonSignIn"
        android:layout_marginTop="20dp"
        android:color="#7EC0EE"
        android:layout_width="fill_parent"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_height="wrap_content"
        android:background="@drawable/rounded_edittext"
        android:clickable="true"
        android:text="Sign In" />

    <TextView
        android:id="@+id/Signup"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:textSize="15dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:clickable="true"
        android:text="@string/signup"/>

    <Button
        android:id="@+id/buttonSignUp"
        android:layout_marginTop="20dp"
        android:color="#7EC0EE"
        android:layout_width="fill_parent"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_height="wrap_content"
        android:background="@drawable/rounded_edittext"
        android:text="Sign Up" />

</LinearLayout>

注册

<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    android:fillViewport="false"
   >
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:gravity="center_vertical" >

    <TextView
        android:id="@+id/username"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:textSize="20dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:text="@string/username"/>

    <EditText
        android:id="@+id/editTextUserName"
        android:hint="User Name"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:textSize="15dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content">
    </EditText>

    <View
        android:layout_width="300dp"
        android:layout_height="2dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:background="#c0c0c0"></View>
    <TextView
        android:id="@+id/Email"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:textSize="20dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:text="@string/Email"/>

    <EditText
        android:id="@+id/emailid"
        android:hint="Emailid"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:textSize="15dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content">
    </EditText>

    <View
        android:layout_width="300dp"
        android:layout_height="2dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:background="#c0c0c0"></View>

    <TextView
        android:id="@+id/Contact"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:textSize="20dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:text="@string/contact"/>

    <EditText
        android:id="@+id/ContactNumber"
        android:hint="Contact Number"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:textSize="15dp"
        android:maxLength="10"
        android:inputType="number"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content">
    </EditText>

    <View
        android:layout_width="300dp"
        android:layout_height="2dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:background="#c0c0c0"></View>   

    <TextView
        android:id="@+id/Password1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:textSize="20dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:text="@string/password1"/>

    <EditText
        android:id="@+id/editTextPassword"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:textSize="15dp"
        android:maxLength="20"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:hint="Password"
        android:inputType="textPassword" />

    <View
        android:layout_width="300dp"
        android:layout_height="2dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:background="#c0c0c0"></View>
    <TextView
        android:id="@+id/confirmPassword1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:textSize="20dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:text="@string/confirmpassword1"/>

    <EditText
        android:id="@+id/editTextConfirmPassword"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_marginLeft="20dp"
        android:layout_marginTop="20dp"
        android:layout_marginRight="20dp"
        android:hint="Confirm Password"
        android:maxLength="20"
        android:inputType="textPassword" />

    <Button
        android:id="@+id/buttonCreateAccount"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Create Account"
        android:layout_marginBottom="60dp"
        android:layout_marginLeft="20dp"
        android:layout_marginTop="20dp"
        android:layout_marginRight="20dp"
        android:background="@drawable/rounded_edittext"/>

</LinearLayout>
    </ScrollView>

注册

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class SignupActivity extends Activity
{
    EditText editTextUserName,editTextPassword,editTextConfirmPassword,emailid,ContactNumber;
    Button btnCreateAccount;

    LoginDataBaseAdapter loginDataBaseAdapter;
    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.signup);

// get Instance of Database Adapter
        loginDataBaseAdapter=new LoginDataBaseAdapter(this);
        loginDataBaseAdapter=loginDataBaseAdapter.open();

// Get Refferences of Views
        editTextUserName=(EditText)findViewById(R.id.editTextUserName);
        editTextPassword=(EditText)findViewById(R.id.editTextPassword);
        editTextConfirmPassword=(EditText)findViewById(R.id.editTextConfirmPassword);
        emailid=(EditText)findViewById(R.id.emailid);
        ContactNumber=(EditText)findViewById(R.id.ContactNumber);

        btnCreateAccount=(Button)findViewById(R.id.buttonCreateAccount);
        btnCreateAccount.setOnClickListener(new View.OnClickListener() {

            public void onClick(View v) {
// TODO Auto-generated method stub

                String userName=editTextUserName.getText().toString();
                String password=editTextPassword.getText().toString();
                String confirmPassword=editTextConfirmPassword.getText().toString();
                String id=emailid.getText().toString();
                String number= ContactNumber.getText().toString();

// check if any of the fields are vaccant
                if(userName.equals("")||password.equals("")||confirmPassword.equals(""))
                {
                    Toast.makeText(getApplicationContext(), "Field Vaccant", Toast.LENGTH_LONG).show();
                    return;
                }
// check if both password matches
                if(!password.equals(confirmPassword))
                {
                    Toast.makeText(getApplicationContext(), "Password does not match", Toast.LENGTH_LONG).show();
                    return;
                }



              /*  if(!emailid(isValidEmail(charSequence target)))
                {



                }*/
                else
                {
// Save the Data in Database
                    loginDataBaseAdapter.insertEntry(number, password);
                    Toast.makeText(getApplicationContext(), "Account Successfully Created ", Toast.LENGTH_LONG).show();
                }

            }
        });
    }

    public final static boolean isValidEmail(CharSequence target) {
        if (target == null) {
            return false;
        } else {
            return android.util.Patterns.EMAIL_ADDRESS.matcher(target).matches();
        }
    }
    @Override
    protected void onDestroy() {
// TODO Auto-generated method stub
        super.onDestroy();

        loginDataBaseAdapter.close();
    }
}

logindatabaseadapter

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;

public class LoginDataBaseAdapter
{
    static final String DATABASE_NAME = "login.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.
    static final String DATABASE_CREATE = "create table "+"LOGIN"+
            "( " +"ID"+" integer primary key autoincrement,"+ "USERNAME text,PASSWORD text); ";
    // 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 void insertEntry(String userName,String password)
    {
        ContentValues newValues = new ContentValues();
// Assign values for each row.
        newValues.put("USERNAME", userName);
        newValues.put("PASSWORD",password);

// Insert the row into your table
        db.insert("LOGIN", null, newValues);
///Toast.makeText(context, "Reminder Is Successfully Saved", Toast.LENGTH_LONG).show();
    }
    public int deleteEntry(String UserName)
    {
//String id=String.valueOf(ID);
        String where="USERNAME=?";
        int numberOFEntriesDeleted= db.delete("LOGIN", where, new String[]{UserName}) ;
// Toast.makeText(context, "Number fo Entry Deleted Successfully : "+numberOFEntriesDeleted, Toast.LENGTH_LONG).show();
        return numberOFEntriesDeleted;
    }
    public String getSinlgeEntry(String userName)
    {
        Cursor cursor=db.query("LOGIN", 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 void updateEntry(String userName,String password)
    {
// Define the updated row content.
        ContentValues updatedValues = new ContentValues();
// Assign values for each row.
        updatedValues.put("USERNAME", userName);
        updatedValues.put("PASSWORD",password);

        String where="USERNAME = ?";
        db.update("LOGIN",updatedValues, where, new String[]{userName});
    }
}

databasehelper

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;

/**
 * Created by Neha Thakur on 5/23/2016.
 */
public class DataBaseHelper  extends SQLiteOpenHelper
{
    public DataBaseHelper(Context context, String name, SQLiteDatabase.CursorFactory factory, int version)
    {
        super(context, name, factory, version);
    }
    // Called when no database exists in disk and the helper class needs
// to create a new one.
    @Override
    public void onCreate(SQLiteDatabase _db)
    {
        _db.execSQL(LoginDataBaseAdapter.DATABASE_CREATE);

    }
    // Called when there is a database version mismatch meaning that the version
// of the database on disk needs to be upgraded to the current version.
    @Override
    public void onUpgrade(SQLiteDatabase _db, int _oldVersion, int _newVersion)
    {
// Log the version upgrade.
        Log.w("TaskDBAdapter", "Upgrading from version " +_oldVersion + " to " +_newVersion + ", which will destroy all old data");

// Upgrade the existing database to conform to the new version. Multiple
// previous versions can be handled by comparing _oldVersion and _newVersion
// values.
// The simplest case is to drop the old table and create a new one.
        _db.execSQL("DROP TABLE IF EXISTS " + "TEMPLATE");
// Create a new one.
        onCreate(_db);
    }

}

登入

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <TextView
        android:id="@+id/Mobileno"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="60dp"
        android:layout_gravity="center"
        android:textSize="20dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:text="@string/Registeresd_Mobile_Number"/>

    <EditText
        android:id="@+id/editTextUserNameToLogin"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_gravity="center"
        android:inputType="number"
        android:maxLength="10"
        android:hint="Mobile Number">
    </EditText>

    <View
        android:layout_width="300dp"
        android:layout_height="2dp"
        android:layout_marginTop="20dp"
        android:layout_marginLeft="15dp"
        android:layout_marginRight="15dp"
        android:layout_gravity="center"
        android:background="#c0c0c0"></View>

    <TextView
        android:id="@+id/editTextPassword"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:textSize="20dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:text="@string/password"/>

    <EditText
        android:id="@+id/editTextPasswordToLogin"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_gravity="center"
        android:maxLength="20"
        android:inputType="textPassword"
        android:hint="Password" />

    <View
        android:layout_width="300dp"
        android:layout_height="2dp"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        android:background="#c0c0c0"></View>

    <Button
        android:id="@+id/buttonSignIn"
        android:layout_marginTop="20dp"
        android:color="#7EC0EE"
        android:layout_width="fill_parent"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_height="wrap_content"
        android:background="@drawable/rounded_edittext"
        android:text="Sign In" />
</LinearLayout>

Answer 1

也将onClick方法添加到signIn按钮。

<Button

        android:id="@+id/buttonSignIn"
        android:layout_marginTop="20dp"
        android:color="#7EC0EE"
        android:layout_width="fill_parent"
        android:layout_marginLeft="20dp"
        android:layout_marginRight="20dp"
        android:layout_height="wrap_content"
        android:background="@drawable/rounded_edittext"
        <!-- Here -->
        android:onClick="SignIn"
        android:clickable="true"
        android:text="Sign In" />

SIgn IN在Android中注册Sqlite。无法解决

1 个答案: