java.lang.RuntimeException: Kann nicht instanziiert Aktivität ComponentInfo/ist nicht zugänglich von Klasse

Question

Ich versuche, eine App zu starten und sobald ich einen Menüeintrag auswählen, funktioniert die Anwendung nicht mehr und ich bekomme folgende Fehler:

logcat: 
    03-23 19:54:11.029: E/AndroidRuntime(1316): FATAL EXCEPTION: main 
03-23 19:54:11.029: E/AndroidRuntime(1316): Process: com.example.testcalnd2, PID: 1316 
03-23 19:54:11.029: E/AndroidRuntime(1316): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.testcalnd2/com.example.testcalnd2.ActivityDiaryEdit}: java.lang.IllegalAccessException: class com.example.testcalnd2.ActivityDiaryEdit is not accessible from class android.app.Instrumentation 
03-23 19:54:11.029: E/AndroidRuntime(1316):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2236) 
03-23 19:54:11.029: E/AndroidRuntime(1316):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2390) 
03-23 19:54:11.029: E/AndroidRuntime(1316):  at android.app.ActivityThread.access$800(ActivityThread.java:151) 
03-23 19:54:11.029: E/AndroidRuntime(1316):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303) 
03-23 19:54:11.029: E/AndroidRuntime(1316):  at android.os.Handler.dispatchMessage(Handler.java:102) 
03-23 19:54:11.029: E/AndroidRuntime(1316):  at android.os.Looper.loop(Looper.java:135) 
03-23 19:54:11.029: E/AndroidRuntime(1316):  at android.app.ActivityThread.main(ActivityThread.java:5257) 
03-23 19:54:11.029: E/AndroidRuntime(1316):  at java.lang.reflect.Method.invoke(Native Method) 
03-23 19:54:11.029: E/AndroidRuntime(1316):  at java.lang.reflect.Method.invoke(Method.java:372) 
03-23 19:54:11.029: E/AndroidRuntime(1316):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903) 
03-23 19:54:11.029: E/AndroidRuntime(1316):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698) 
03-23 19:54:11.029: E/AndroidRuntime(1316): Caused by: java.lang.IllegalAccessException: class com.example.testcalnd2.ActivityDiaryEdit is not accessible from class android.app.Instrumentation 
03-23 19:54:11.029: E/AndroidRuntime(1316):  at java.lang.Class.newInstance(Class.java:1591) 
03-23 19:54:11.029: E/AndroidRuntime(1316):  at android.app.Instrumentation.newActivity(Instrumentation.java:1066) 
03-23 19:54:11.029: E/AndroidRuntime(1316):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2226) 
03-23 19:54:11.029: E/AndroidRuntime(1316):  ... 10 more 
03-23 19:54:20.399: I/Process(1316): Sending signal. PID: 1316 SIG: 9 

MainActivity Klasse:

package com.example.testcalnd2; 

import android.app.Activity; 
import android.app.ListActivity; 
import android.content.Intent; 
import android.database.Cursor; 
import android.os.Bundle; 
import android.support.v4.widget.SimpleCursorAdapter; 
import android.view.Menu; 
import android.view.MenuItem; 
import android.view.View; 
import android.widget.ListView; 

public class MainActivity extends ListActivity { 
     private static final int ACTIVITY_CREATE = 0; 
     private static final int ACTIVITY_EDIT = 1; 

     private static final int INSERT_ID = Menu.FIRST; 
     private static final int DELETE_ID = Menu.FIRST + 1; 

     private DiaryDbAdapter mDbHelper; 
     private Cursor mDiaryCursor; 

     @Override 
     public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.diary_list); 
     mDbHelper = new DiaryDbAdapter(this); 
     mDbHelper.open(); 
     renderListView(); 

     } 

     private void renderListView() { 
     mDiaryCursor = mDbHelper.getAllNotes(); 
     startManagingCursor(mDiaryCursor); 
     String[] from = new String[] { DiaryDbAdapter.KEY_TITLE, 
      DiaryDbAdapter.KEY_CREATED }; 
     int[] to = new int[] { R.id.text1, R.id.created }; 
     SimpleCursorAdapter notes = new SimpleCursorAdapter(this, 
      R.layout.diary_now, mDiaryCursor, from, to); 
     setListAdapter(notes); 
     } 

     @Override 
     public boolean onCreateOptionsMenu(Menu menu) { 
     super.onCreateOptionsMenu(menu); 
     menu.add(0, INSERT_ID, 0, R.string.menu_insert); 
     menu.add(0, DELETE_ID, 0, R.string.menu_delete); 
     return true; 
    } 

     @Override 
     public boolean onMenuItemSelected(int featureId, MenuItem item) { 
     switch (item.getItemId()) { 
     case INSERT_ID: 
      createDiary(); 
      return true; 
     case DELETE_ID: 
      mDbHelper.deleteDiary(getListView().getSelectedItemId()); 
      renderListView(); 
      return true; 
     } 
     return super.onMenuItemSelected(featureId, item); 
     } 

     private void createDiary() { 
     Intent i = new Intent(this, ActivityDiaryEdit.class); 
     startActivityForResult(i, ACTIVITY_CREATE); 
     } 

     @Override 

     protected void onListItemClick(ListView l, View v, int position, long id) { 
     super.onListItemClick(l, v, position, id); 
     Cursor c = mDiaryCursor; 
     c.moveToPosition(position); 
     Intent i = new Intent(this, ActivityDiaryEdit.class); 
     i.putExtra(DiaryDbAdapter.KEY_ROWID, id); 
     i.putExtra(DiaryDbAdapter.KEY_TITLE, c.getString(c 
      .getColumnIndexOrThrow(DiaryDbAdapter.KEY_TITLE))); 
     i.putExtra(DiaryDbAdapter.KEY_BODY, c.getString(c 
      .getColumnIndexOrThrow(DiaryDbAdapter.KEY_BODY))); 
     startActivityForResult(i, ACTIVITY_EDIT); 
     } 

     @Override 
     protected void onActivityResult(int requestCode, int resultCode, 
      Intent intent) { 
     super.onActivityResult(requestCode, resultCode, intent); 
     renderListView(); 
     } 
    } 


package com.example.testcalnd2; 

import android.app.ListActivity; 
import android.content.Intent; 
import android.database.Cursor; 
import android.os.Bundle; 
import android.view.Menu; 
import android.view.MenuItem; 
import android.view.View; 
import android.widget.ListView; 
import android.widget.SimpleCursorAdapter; 

DiaryDbAdapter:

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

import java.util.Calendar; 
import java.util.Date; 

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

class DiaryDbAdapter { 

    public static final String KEY_TITLE = "title"; 
    public static final String KEY_BODY = "body"; 
    public static final String KEY_ROWID = "_id"; 
    public static final String KEY_CREATED = "created"; 

    private static final String TAG = "DiaryDbAdapter"; 
    private DatabaseHelper mDbHelper; 
    private SQLiteDatabase mDb; 

    private static final String DATABASE_CREATE = "create table diary (_id integer primary key autoincrement, " 
     + "title text not null, body text not null, created text not null);"; 

    private static final String DATABASE_NAME = "database"; 
    private static final String DATABASE_TABLE = "diary"; 
    private static final int DATABASE_VERSION = 1; 

    private final Context mCtx; 

    private static class DatabaseHelper extends SQLiteOpenHelper { 

    DatabaseHelper(Context context) { 
     super(context, DATABASE_NAME, null, DATABASE_VERSION); 
    } 

    @Override 
    public void onCreate(SQLiteDatabase db) { 
     db.execSQL(DATABASE_CREATE); 
    } 

    @Override 
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { 
     db.execSQL("DROP TABLE IF EXISTS diary"); 
     onCreate(db); 
    } 
    } 

    public DiaryDbAdapter(Context ctx) { 
    this.mCtx = ctx; 
    } 

    public DiaryDbAdapter open() throws SQLException { 
    mDbHelper = new DatabaseHelper(mCtx); 
    mDb = mDbHelper.getWritableDatabase(); 
    return this; 
    } 

    public void closeclose() { 
    mDbHelper.close(); 
    } 

    public long createDiary(String title, String body) { 
    ContentValues initialValues = new ContentValues(); 
    initialValues.put(KEY_TITLE, title); 
    initialValues.put(KEY_BODY, body); 
    Calendar calendar = Calendar.getInstance(); 
    String created = calendar.get(Calendar.YEAR) + "" 
     + calendar.get(Calendar.MONTH) + "" 
     + calendar.get(Calendar.DAY_OF_MONTH) + "" 
     + calendar.get(Calendar.HOUR_OF_DAY) + "" 
     + calendar.get(Calendar.MINUTE) + ""; 
    initialValues.put(KEY_CREATED, created); 
    return mDb.insert(DATABASE_TABLE, null, initialValues); 
    } 

    public boolean deleteDiary(long rowId) { 

    return mDb.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0; 
    } 

    public Cursor getAllNotes() { 

    return mDb.query(DATABASE_TABLE, new String[] { KEY_ROWID, KEY_TITLE, 
     KEY_BODY, KEY_CREATED }, null, null, null, null, null); 
    } 

    public Cursor getDiary(long rowId) throws SQLException { 

    Cursor mCursor = 

    mDb.query(true, DATABASE_TABLE, new String[] { KEY_ROWID, KEY_TITLE, 
     KEY_BODY, KEY_CREATED }, KEY_ROWID + "=" + rowId, null, null, 
     null, null, null); 
    if (mCursor != null) { 
     mCursor.moveToFirst(); 
    } 
    return mCursor; 

    } 

    public boolean updateDiary(long rowId, String title, String body) { 
    ContentValues args = new ContentValues(); 
    args.put(KEY_TITLE, title); 
    args.put(KEY_BODY, body); 
    Calendar calendar = Calendar.getInstance(); 
    String created = calendar.get(Calendar.YEAR) + "" 
     + calendar.get(Calendar.MONTH) + "" 
     + calendar.get(Calendar.DAY_OF_MONTH) + "" 
     + calendar.get(Calendar.HOUR_OF_DAY) + "" 
     + calendar.get(Calendar.MINUTE) + ""; 
    args.put(KEY_CREATED, created); 

    return mDb.update(DATABASE_TABLE, args, KEY_ROWID + "=" + rowId, null) > 0; 
    } 
} 

ActivityDiaryEdit Aktivität:

class ActivityDiaryEdit extends Activity { 

    private EditText mTitleText; 
    private EditText mBodyText; 
    private Long mRowId; 
    private DiaryDbAdapter mDbHelper; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    mDbHelper = new DiaryDbAdapter(this); 
    mDbHelper.open(); 
    setContentView(R.layout.diary_edit); 

    mTitleText = (EditText) findViewById(R.id.title); 
    mBodyText = (EditText) findViewById(R.id.body); 

    Button confirmButton = (Button) findViewById(R.id.confirm); 

    mRowId = null; 
    Bundle extras = getIntent().getExtras(); 
    if (extras != null) { 
     String title = extras.getString(DiaryDbAdapter.KEY_TITLE); 
     String body = extras.getString(DiaryDbAdapter.KEY_BODY); 
     mRowId = extras.getLong(DiaryDbAdapter.KEY_ROWID); 

     if (title != null) { 
     mTitleText.setText(title); 
     } 
     if (body != null) { 
     mBodyText.setText(body); 
     } 
    } 

    confirmButton.setOnClickListener(new View.OnClickListener() { 
     public void onClick(View view) { 
     String title = mTitleText.getText().toString(); 
     String body = mBodyText.getText().toString(); 
     if (mRowId != null) { 
      mDbHelper.updateDiary(mRowId, title, body); 
     } else 
      mDbHelper.createDiary(title, body); 
     Intent mIntent = new Intent(); 
     setResult(RESULT_OK, mIntent); 
     finish(); 
     } 

    }); 
    } 
} 

manifestieren:

<?xml version="1.0" encoding="utf-8"?> 
<manifest xmlns:android="http://schemas.android.com/apk/res/android" 
    package="com.example.testcalnd2" 
    android:versionCode="1" 
    android:versionName="1.0" > 

    <uses-sdk 
     android:minSdkVersion="14" 
     android:targetSdkVersion="22" /> 

    <application 
     android:allowBackup="true" 
     android:icon="@drawable/ic_launcher" 
     android:label="@string/app_name" 
     android:theme="@style/AppTheme" > 
     <activity 
      android:name=".MainActivity" 
      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=".DiaryDbAdapter" 
      android:label="@string/title_activity_diary_db_adapter" > 
     </activity> 
     <activity 
       android:name="com.example.testcalnd2.ActivityDiaryEdit"> 

</activity> 

    </application> 

</manifest> 

Answer 1

Machen Sie Ihre Klasse ActivityDiaryEdit Öffentlichkeit wie folgt aus:

public class ActivityDiaryEdit extends Activity { 
    ... 

Hope this hilft !!