Невозможно запустить Activity ComponentInfo {} java.lang.nullPointerException

Question

Я все еще участвую в изучении Java, поэтому я сожалею, если этот вопрос слишком очевиден. Я пытаюсь запустить свое приложение, и оно вызывает эту ошибку. Проблема, кажется, в методе OnCreate(), но я не могу понять, что вызывает ее.

import java.util.Calendar; 

import android.app.Activity; 
import android.app.AlertDialog; 
import android.app.DatePickerDialog; 
import android.app.Dialog; 
import android.app.DialogFragment; 
import android.content.Intent; 
import android.os.Bundle; 
import android.view.Menu; 
import android.view.View; 
import android.view.View.OnClickListener; 
import android.widget.Button; 
import android.widget.CheckBox; 
import android.widget.DatePicker; 
import android.widget.EditText; 
import android.widget.RadioGroup; 
import android.widget.Toast; 

public class MainActivity extends Activity { 
    public final static String NAME = "nick.miros.famous.problems.MESSAGE"; 
    public final static String EMAIL = "nick.miros.famous.problems.MESSAGE1"; 
    public final static String STUFFSEX = "nick.miros.famous.problems.MESSAGE2"; 
    public final static String BIRTHDAY = "nick.miros.famous.problems.MESSAGE3"; 

    private boolean agreed; 
    private String sex; 
    public static String bornDate; 
    public EditText emailEdit; 
    public EditText nameEdit; 
    public EditText passwordEdit; 
    // public EditText passwordRepeatEdit; 
    public RadioGroup radioSex; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 
     nameEdit = (EditText) findViewById(R.id.name); 
     emailEdit = (EditText) findViewById(R.id.email); 
     passwordEdit = (EditText) findViewById(R.id.password); 
     // passwordRepeatEdit = (EditText) findViewById(R.id.passwordRepeat); 

     emailEdit.addTextChangedListener(new GenericTextWatcher(emailEdit)); 
     nameEdit.addTextChangedListener(new GenericTextWatcher(nameEdit)); 
     passwordEdit 
       .addTextChangedListener(new GenericTextWatcher(passwordEdit)); 
     // passwordRepeatEdit.addTextChangedListener(new 
     // GenericTextWatcher(passwordRepeatEdit)); 

     Button Go = (Button) findViewById(R.id.sendButton); 
     Go.setOnClickListener(new OnClickListener() { 

      @Override 
      public void onClick(View v) { 
       // TODO Auto-generated method stub 
       sendAndCheck(); 
      } 
     }); 

    } 

    @Override 
    public boolean onCreateOptionsMenu(Menu menu) { 
     // Inflate the menu; this adds items to the action bar if it is present. 
     getMenuInflater().inflate(R.menu.main, menu); 
     return true; 
    } 

    private String getSex(int id) { 

     switch (id) { 

     case R.id.radioMale: 
      sex = "Male"; 
      break; 
     case R.id.radioFemale: 
      sex = "Female"; 
      break; 
     } 
     return sex; 
    } 

    public void showThanks() { 
     Toast.makeText(this.getApplicationContext(), R.string.thank_you, 
       Toast.LENGTH_LONG).show(); 
    } 

    public void onCheckBoxClicked(View view) { 
     // Is the view now checked? 
     agreed = ((CheckBox) findViewById(R.id.agreementBox)).isChecked(); 
    } 

    public final static boolean isValidEmail(CharSequence target) { 
     if (target == null) { 
      return false; 
     } else { 
      return android.util.Patterns.EMAIL_ADDRESS.matcher(target) 
        .matches(); 
     } 
    } 

    public static class DatePickerFragment extends DialogFragment implements 
      DatePickerDialog.OnDateSetListener { 

     @Override 
     public Dialog onCreateDialog(Bundle savedInstanceState) { 
      // Use the current date as the default date in the picker 
      final Calendar c = Calendar.getInstance(); 
      int year = c.get(Calendar.YEAR); 
      int month = c.get(Calendar.MONTH); 
      int day = c.get(Calendar.DAY_OF_MONTH); 

      // Create a new instance of DatePickerDialog and return it 
      return new DatePickerDialog(getActivity(), this, year, month, day); 
     } 

     public void onDateSet(DatePicker view, int year, int month, int day) { 
      // Do something with the date chosen by the user 
      bornDate = Integer.toString(year) + "/" + Integer.toString(month) 
        + "/" + Integer.toString(day); 
     } 
    } 

    public void showDatePickerDialog(View v) { 
     DialogFragment newFragment = new DatePickerFragment(); 
     newFragment.show(getFragmentManager(), "datePicker"); 
    } 

    /** Called when the user clicks the Send button */ 
    public void sendAndCheck() { 

     CharSequence emailToCheck = ((EditText) findViewById(R.id.email)) 
       .getText().toString(); 

     if (agreed) { 
      // Do something in response to button 

      if (isValidEmail(emailToCheck)) { 
       Intent intent = new Intent(this, DisplayMessageActivity.class); 
       String sent_name = ((EditText) findViewById(R.id.name)) 
         .getText().toString(); 
       String sent_email = ((EditText) findViewById(R.id.email)) 
         .getText().toString(); 
       int id = ((RadioGroup) findViewById(R.id.radioSex)) 
         .getCheckedRadioButtonId(); 
       String sent_sex = getSex(id); 
       String sent_birthday = bornDate; 
       intent.putExtra(NAME, sent_name); 
       intent.putExtra(EMAIL, sent_email); 
       intent.putExtra(STUFFSEX, sent_sex); 
       intent.putExtra(BIRTHDAY, sent_birthday); 
       startActivity(intent); 
       showThanks(); 

      } else { 
       ((EditText) findViewById(R.id.email)).setError("wrong email!"); 
      } 

     } else { 
      AlertDialog.Builder Alert = new AlertDialog.Builder(this); 

      Alert.setMessage("Please agree with the terms and conditions first"); 
      Alert.setTitle("Notice"); 
      Alert.setPositiveButton("OK", null); 
      Alert.setCancelable(true); 
      Alert.create().show(); 
     } 
    } 

} 

Вот GenericTextWatcher:

import java.util.regex.Matcher; 
import java.util.regex.Pattern; 

import android.text.Editable; 
import android.text.TextWatcher; 
import android.view.View; 
import android.widget.EditText; 

public class GenericTextWatcher implements TextWatcher{ 

    private View view; 
    private PasswordValidator passwordValidator = new PasswordValidator(); 
    String password = ((EditText) view).getText().toString(); 
    GenericTextWatcher(View view) { 
     this.view = view; 
    } 

    public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {} 
    public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {} 

    public void afterTextChanged(Editable editable) { 
     String text = editable.toString(); 
     switch(view.getId()){ 
      case R.id.name: 
       if (!(text.equals(""))) 
       { 

       } 
       else 
       { 
        ((EditText) view).setError("wrong name!"); 
       } 
       break; 
      case R.id.email: 
       CharSequence emailToCheck = ((EditText) view).getText().toString(); 
       if (isValidEmail(emailToCheck)) 
       { 

       } 
       else 
       { 
        ((EditText) view).setError("wrong email!"); 

       } 

       break; 
      case R.id.password: 
       if (passwordValidator.isValidPassword(text)) 
       { 

       } 
       else 
       { 
        ((EditText) view).setError("must have 1 uppercase letter, 1 number and be 6 characters long"); 
       } 
       break; 
      /* case R.id.passwordRepeat: 
       String password = (((EditText) view) findViewById(R.id.password).getText().toString(); 
       if (text.equals(password)) 
       { 

       } 
       else 
       { 
        ((EditText) view).setError("passwords don't match"); 
       } 
       break;*/ 
     } 
    } 

    public final static boolean isValidEmail(CharSequence target) { 
     if (target == null) { 
      return false; 
     } else { 
      return android.util.Patterns.EMAIL_ADDRESS.matcher(target) 
          .matches(); 
     } 
    } 

    public class PasswordValidator{ 

     private Pattern pattern; 
     private Matcher matcher; 

     private static final String PASSWORD_PATTERN = 
       "((?=.*\\d)(?=.*[A-Z]).{6,20})"; 

     public PasswordValidator(){ 
      pattern = Pattern.compile(PASSWORD_PATTERN); 
     } 

     /** 
     * Validate password with regular expression 
     * @param password password for validation 
     * @return true valid password, false invalid password 
     */ 
     public boolean isValidPassword(String password){ 

      matcher = pattern.matcher(password); 
      return matcher.matches(); 

     } 
    } 
} 

Вот LogCat:

02-04 03:59:14.267: D/dalvikvm(2400): GC_FOR_ALLOC freed 37K, 7% free 2640K/2820K, paused 1ms, total 34ms 
02-04 03:59:14.267: I/dalvikvm-heap(2400): Grow heap (frag case) to 3.319MB for 635808-byte allocation 
02-04 03:59:14.277: D/dalvikvm(2400): GC_FOR_ALLOC freed 2K, 6% free 3258K/3444K, paused 10ms, total 10ms 
02-04 03:59:14.377: D/AndroidRuntime(2400): Shutting down VM 
02-04 03:59:14.377: W/dalvikvm(2400): threadid=1: thread exiting with uncaught exception (group=0xb2eb7648) 
02-04 03:59:14.377: E/AndroidRuntime(2400): FATAL EXCEPTION: main 
02-04 03:59:14.377: E/AndroidRuntime(2400): java.lang.RuntimeException: Unable to start activity ComponentInfo{nick.miros.famous.problems/nick.miros.famous.problems.MainActivity}: java.lang.NullPointerException 
02-04 03:59:14.377: E/AndroidRuntime(2400):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2211) 
02-04 03:59:14.377: E/AndroidRuntime(2400):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261) 
02-04 03:59:14.377: E/AndroidRuntime(2400):  at android.app.ActivityThread.access$600(ActivityThread.java:141) 
02-04 03:59:14.377: E/AndroidRuntime(2400):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256) 
02-04 03:59:14.377: E/AndroidRuntime(2400):  at android.os.Handler.dispatchMessage(Handler.java:99) 
02-04 03:59:14.377: E/AndroidRuntime(2400):  at android.os.Looper.loop(Looper.java:137) 
02-04 03:59:14.377: E/AndroidRuntime(2400):  at android.app.ActivityThread.main(ActivityThread.java:5103) 
02-04 03:59:14.377: E/AndroidRuntime(2400):  at java.lang.reflect.Method.invokeNative(Native Method) 
02-04 03:59:14.377: E/AndroidRuntime(2400):  at java.lang.reflect.Method.invoke(Method.java:525) 
02-04 03:59:14.377: E/AndroidRuntime(2400):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737) 
02-04 03:59:14.377: E/AndroidRuntime(2400):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553) 
02-04 03:59:14.377: E/AndroidRuntime(2400):  at dalvik.system.NativeStart.main(Native Method) 
02-04 03:59:14.377: E/AndroidRuntime(2400): Caused by: java.lang.NullPointerException 
02-04 03:59:14.377: E/AndroidRuntime(2400):  at nick.miros.famous.problems.GenericTextWatcher.<init>(GenericTextWatcher.java:15) 
02-04 03:59:14.377: E/AndroidRuntime(2400):  at nick.miros.famous.problems.MainActivity.onCreate(MainActivity.java:46) 
02-04 03:59:14.377: E/AndroidRuntime(2400):  at android.app.Activity.performCreate(Activity.java:5133) 
02-04 03:59:14.377: E/AndroidRuntime(2400):  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087) 
02-04 03:59:14.377: E/AndroidRuntime(2400):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2175) 
02-04 03:59:14.377: E/AndroidRuntime(2400):  ... 11 more 

Answer 1

Там находится в GenericTextWatcher инициализации (<init>) а NullPointerException, по линии 15.

В там у вас есть переменная-член:

String password = ((EditText) view).getText().toString(); 

view является null на данный момент, вы только назначить его в конструкторе позже. Переместите этот код в конструктор или позже.