活动不幸关闭错误

Question

主要活动：在该行获取错误：

final TextView registerpage = (TextView) findViewById(R.id.register);   
    registerpage.setOnClickListener(new OnClickListener(){  

package com.example.indianrecipe;

import android.app.Activity;
import android.content.Intent;
import android.database.Cursor;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

public class Login extends  Activity {

    public void onCreate(Bundle savedInstanceState)   
    {  
      super.onCreate(savedInstanceState);  

    setContentView(R.layout.loginpage);  

    final TextView txt_username = (TextView) findViewById(R.id.name);  

    final TextView txt_psw = (TextView) findViewById(R.id.pass);  

    Button btn_signin=(Button) findViewById(R.id.signinb);  



    btn_signin.setOnClickListener(new OnClickListener(){  

    public void onClick(View v) {  

    RegisterHandler db= new RegisterHandler(getBaseContext());  
    db.onOpen(null);  
    Log.v("LoginDetails", txt_username.getText().toString()+"../.."+txt_psw.getText().toString());  
    Cursor cur = db.get_info( txt_username.getText().toString() , txt_psw.getText().toString());  
    if(cur.getCount()!=0)  
    {
        Log.v("Login",cur.getString(3));  
        String password=cur.getString(0);   


        Intent i = new Intent(Login.this, FullscreenActivity.class);  
        i.putExtra("USERNAME", txt_username.getText().toString());  
        i.putExtra("PASSWORD", txt_psw.getText().toString());   
        startActivity(i);  

        db.close();  
        }  
        else  
        Toast.makeText(getBaseContext(), "Please enter Valid User name and password", Toast.LENGTH_LONG).show();  
        }});   




    final TextView registerpage = (TextView) findViewById(R.id.register);   
    registerpage.setOnClickListener(new OnClickListener(){  

        public void onClick(View v) {
            System.out.println("error here==" + registerpage);

        setContentView(R.layout.register_user); 

    }
    });

    Button reg_btn=(Button) findViewById(R.id.regbtn);  
    reg_btn.setOnClickListener(new OnClickListener(){
        public void onClick(View v) {

    RegisterHandler db= new RegisterHandler(getBaseContext());  
        final EditText cuisine= (EditText) findViewById(R.id.fav_cuisine); 
        final EditText email= (EditText) findViewById(R.id.email_id);
        final EditText name= (EditText) findViewById(R.id.person_name);
        final EditText password= (EditText) findViewById(R.id.pass_reg);

    db.addUser(cuisine.toString(),email.toString(),name.toString(),password.toString());

    }
    });

    }

}

快照清单文件：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.indianrecipe"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="18" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name="com.example.indianrecipe.Login"
            android:configChanges="orientation|keyboardHidden|screenSize"
            android:label="@string/app_name">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

            <activity
            android:name="com.example.indianrecipe.FullscreenActivity"
            android:configChanges="orientation|keyboardHidden|screenSize"
            android:label="@string/app_name">
            </activity>
    </application>

</manifest>

继承logcat： 这是logcat

ComponentInfo{com.example.indianrecipe/com.example.indianrecipe.Login}: java.lang.NullPointerException
01-22 08:08:12.650: E/AndroidRuntime(1051):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2176)
01-22 08:08:12.650: E/AndroidRuntime(1051):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2226)
01-22 08:08:12.650: E/AndroidRuntime(1051):     at android.app.ActivityThread.access$700(ActivityThread.java:135)
01-22 08:08:12.650: E/AndroidRuntime(1051):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1397)
01-22 08:08:12.650: E/AndroidRuntime(1051):     at android.os.Handler.dispatchMessage(Handler.java:102)
 E/AndroidRuntime(1051):    at android.os.Looper.loop(Looper.java:137)
01-22 08:08:12.650: E/AndroidRuntime(1051):     at android.app.ActivityThread.main(ActivityThread.java:4998)
 E/AndroidRuntime(1051):    at java.lang.reflect.Method.invokeNative(Native Method)
 E/AndroidRuntime(1051):    at java.lang.reflect.Method.invoke(Method.java:515)
01-22 08:08:12.650: E/AndroidRuntime(1051):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:777) E/AndroidRuntime(1051):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:593)
 E/AndroidRuntime(1051):    at dalvik.system.NativeStart.main(Native Method)
 E/AndroidRuntime(1051): Caused by: java.lang.NullPointerException
E/AndroidRuntime(1051):     at com.example.indianrecipe.Login.onCreate(Login.java:71)

xml文件中的寄存器ID：

<TextView
        android:id="@+id/register"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBaseline="@+id/nomem"
        android:layout_alignBottom="@+id/nomem"
        android:layout_toRightOf="@+id/nomem"
        android:clickable="true"
        android:text="@string/register" />