爪哇致命異常onClick

Question

你好，我單擊我的按鈕時出現奇怪的錯誤。它之前工作正常：它停止工作，我不知道爲什麼。你能幫我嗎？下面是代碼：

public void onClick(View view) { 
    switch (view.getId()) { 
     case R.id.bPrisijungti: 
      String elpastas = etElpastas.getText().toString(); 
      String slaptazodis = etSlaptazodis.getText().toString(); 

      User user = new User(elpastas, slaptazodis,"","",""); 

      authenticate(user); 
      break; 
     case R.id.tvRegistracija: 
      Intent registerIntent = new Intent(Login.this, Register.class); 
      startActivity(registerIntent); 
      break; 
    } 
} 

我得到的字符串elpastas錯誤...

XML：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:tools="http://schemas.android.com/tools" 
    android:layout_width="match_parent" 
    android:padding="10dp" 
    android:orientation="vertical" 
    android:layout_height="match_parent"> 


    <TextView 
     android:text="El paštas" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" /> 

    <EditText 
     android:id="@+id/etelpastas" 
     android:layout_width="match_parent" 
     android:layout_marginBottom="10dp" 
     android:layout_height="wrap_content" /> 

    <TextView 
     android:text="Slaptažodis" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" /> 

    <EditText 
     android:id="@+id/etSlaptazodis" 
     android:layout_width="match_parent" 
     android:inputType="textPassword" 
     android:layout_marginBottom="10dp" 
     android:layout_height="wrap_content" /> 

    <Button 
     android:id="@+id/bPrisijungti" 
     android:layout_width="match_parent" 
     android:layout_marginBottom="10dp" 
     android:layout_height="wrap_content" 
     android:text="Prisijungti" /> 

    <TextView 
     android:id="@+id/tvRegistracija" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_gravity="center_horizontal" 
     android:text="Naujas vartotojas" 
     android:textStyle="bold" /> 

</LinearLayout> 

的logcat：

05-25 21:04:57.094 9100-9100/com.tonikamitv.loginregister D/OpenGLRenderer﹕ Enabling debug mode 0 
05-25 21:04:58.384 9100-9100/com.tonikamitv.loginregister D/AndroidRuntime﹕ Shutting down VM 
05-25 21:04:58.384 9100-9100/com.tonikamitv.loginregister W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0x41241438) 
05-25 21:04:58.424 9100-9100/com.tonikamitv.loginregister E/AndroidRuntime﹕ FATAL EXCEPTION: main 
    java.lang.NullPointerException 
      at com.tonikamitv.loginregister.Login.onClick(Login.java:40) 
      at android.view.View.performClick(View.java:4191) 
      at android.view.View$PerformClick.run(View.java:17229) 
      at android.os.Handler.handleCallback(Handler.java:615) 
      at android.os.Handler.dispatchMessage(Handler.java:92) 
      at android.os.Looper.loop(Looper.java:137) 
      at android.app.ActivityThread.main(ActivityThread.java:4960) 
      at java.lang.reflect.Method.invokeNative(Native Method) 
      at java.lang.reflect.Method.invoke(Method.java:511) 
      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1038) 
      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:805) 
      at dalvik.system.NativeStart.main(Native Method) 

Answer 1

你有沒有這樣做過的onclick。我認爲這是根本原因。

EditText etElpastas=(EditText)findViewById(R.id.etelpastas);