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失败登录验证Android

2013-02-15 187 views
1

我尝试登录Android屏幕时遇到了很大问题。我有两个领域，需要用户输入电子邮件和密码，它应该去检查sqlite数据库，如果他们将被导航到主屏幕（登录成功），如果不正确，他们将通过吐司消息通知。我的问题是当我登录按钮我的应用程序显示“不幸停止工作”我不能看到我的代码中的任何错误！请人帮忙！我的代码下面贴 * LoginActivity失败登录验证Android

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的

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

来源

2013-02-15 user1877082

+0

我想你还没有打开像db.open SQLite数据库（）可能是例外，是由于到 – 2013-02-15 12:02:56

+0

我打开数据库通过调用SQLiteDatabase db = new SQLiteAdapter（LoginActivity.this）.openToWrite（） – user1877082 2013-02-15 12:08:30

+0

抱歉，我的坏我没有看到。什么代码就是你的LoginActivity.java:62行请告诉我们 – 2013-02-15 12:10:04

回答

1

你的问题就出现在这条线：

db.rawQuery("SELECT email FROM MY_USERS_TABLE WHERE email= ? AND password=?", new String[] {uname, pass})

发生了什么事情就是即使if sta tement输出一个Toast来表示edittext是空的，这部分被执行，所以uname和pass为空，这会给你IllegalArgumentException: the bind value at index 2 is null错误，因为你正在传递SQL函数的空值。

简单的解决方法：只执行的代码的底部，如果值不为空或为空：

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(); 

     } else { 

      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(); 

      } 
     } 
    } 
}

来源

2013-02-15 12:05:05

+0

谢谢，但我对android很陌生，不知道该怎么做 – user1877082 2013-02-15 12:07:28

+1

这不是一个真正的Android问题，更多的是一般的代码逻辑和流程问题。我已经更新了我的答案，并对代码进行了处理 - 它只是放入一个'else'语句，并移动'（if view == ...'end brace来覆盖整个方法 – 2013-02-15 12:10:06

+0

你是最棒的！ ！我花了这么多时间，已经涨到了一半，非常感谢你:) – user1877082 2013-02-15 12:18:25

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