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onItemClickListener（）崩潰應用程序

2015-12-09 21 views
0

我想在我的Activity_main上點擊listview上的條目以查看Activity_View上的詳細信息。onItemClickListener（）崩潰應用程序

當我這樣做，我的應用程序崩潰。

我的編碼錯在哪裏？

activity_main.xml中

<?xml version="1.0" encoding="utf-8"?> 
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" 
android:layout_height="match_parent" android:paddingLeft="@dimen/activity_horizontal_margin" 
android:paddingRight="@dimen/activity_horizontal_margin" 
android:paddingTop="@dimen/activity_vertical_margin" 
android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity"> 

<LinearLayout 
    android:orientation="vertical" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:layout_alignParentTop="true" 
    android:layout_alignParentLeft="true" 
    android:layout_alignParentStart="true" 
    android:weightSum="1"> 

    <LinearLayout 
     android:orientation="vertical" 
     android:layout_width="match_parent" 
     android:layout_height="71dp" 
     android:layout_weight="0.35"> 

     <LinearLayout 
      android:orientation="horizontal" 
      android:layout_width="match_parent" 
      android:layout_height="wrap_content" 
      android:weightSum="1" 
      android:focusableInTouchMode="true"> 

      <EditText 
       android:layout_width="wrap_content" 
       android:layout_height="wrap_content" 
       android:id="@+id/txtSearch" 
       android:layout_weight="0.98" 
       android:hint="Search..." /> 

      <Button 
       android:layout_width="wrap_content" 
       android:layout_height="wrap_content" 
       android:text="Search" 
       android:id="@+id/btnSearch" /> 
     </LinearLayout> 

     <LinearLayout 
      android:orientation="horizontal" 
      android:layout_width="match_parent" 
      android:layout_height="wrap_content" 
      android:weightSum="1"> 

      <Button 
       android:layout_width="wrap_content" 
       android:layout_height="wrap_content" 
       android:text="Sort By Date" 
       android:id="@+id/btnSortDate" 
       android:layout_gravity="left" 
       android:layout_weight="0.90" /> 

      <Button 
       android:layout_width="174dp" 
       android:layout_height="wrap_content" 
       android:text="Sorty By Title" 
       android:id="@+id/btnSortTitle" 
       android:layout_gravity="right" /> 

     </LinearLayout> 

    </LinearLayout> 

    <ListView 
     android:layout_width="wrap_content" 
     android:layout_height="252dp" 
     android:id="@+id/listView" 
     android:layout_weight="0.56" /> 

    <Button 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:text="Create Entry" 
     android:id="@+id/btnNewEntry" 
     android:layout_gravity="center_horizontal" 
     android:layout_marginTop="10dp" /> 

    </LinearLayout> 

</RelativeLayout>

MainActivity.Java

public class MainActivity extends AppCompatActivity { 

private static final int REQUEST_CODE = 100; 

private static List<Entry> entryList; 

private ListView lvEntries; 
private EntryListAdaptor EntryListadapter; 
DatabaseHandler dbHandler; 
Uri imageUri = Uri.parse("android.resource://unipersonalinc.mypersonalediary/drawable/download.jpg"); 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 
    Button newBtn = (Button) findViewById(R.id.btnNewEntry); 
    lvEntries = (ListView) findViewById(R.id.listView); 
    dbHandler = new DatabaseHandler(getApplicationContext()); 

    entryList = new ArrayList<>(); 
    EntryListadapter = new EntryListAdaptor(); 
    lvEntries.setAdapter(EntryListadapter); 

    newBtn.setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View v) { 
      startActivityForResult(new Intent(MainActivity.this, Activity_Write.class), REQUEST_CODE); 
     } 
    }); 
} 

@Override 
protected void onActivityResult(int requestCode, int resultCode, Intent data) { 
    super.onActivityResult(requestCode, resultCode, data); 
    if (resultCode == Activity.RESULT_OK) { 
     switch (requestCode) { 
      case REQUEST_CODE: 
       if (data != null) { 
        int id = dbHandler.getEntriesCount(); 
        long time = System.currentTimeMillis(); 
        SimpleDateFormat dayTime = new SimpleDateFormat("dd-MM-yyyy mm:ss"); 
        String date = dayTime.format(new Date(time)); 
        String title = data.getStringExtra("Title"); 
        String passage = data.getStringExtra("Passage"); 
        Entry newEntry = new Entry(id, title, passage, imageUri, date); 
        entryList.add(newEntry); 
        dbHandler.createEntry(newEntry); 
        EntryListadapter.notifyDataSetChanged(); 
       } 
       break; 
     } 
    } 
    lvEntries.setOnItemClickListener(new AdapterView.OnItemClickListener() { 
     @Override 
     public void onItemClick(AdapterView<?> parent, View view, int position, long id) { 
      int searchId = position - 1; 
      Cursor cursor = dbHandler.getData(searchId); 
      String entryTitle = cursor.getString(cursor.getColumnIndex(dbHandler.KEY_TITLE)); 
      String entryPassage = cursor.getString(cursor.getColumnIndex(dbHandler.KEY_PASSAGE)); 
      String entryDate = cursor.getString(cursor.getColumnIndex(dbHandler.KEY_DATE)); 

      Bundle dataBundle = new Bundle(); 
      dataBundle.putString("title", entryTitle); 
      dataBundle.putString("passage", entryPassage); 
      dataBundle.putString("date", entryDate); 

      Intent intent = new Intent(getApplicationContext(), Activity_View.class); 
      intent.putExtras(dataBundle); 
      startActivity(intent); 
     } 
    }); 
} 


private class EntryListAdaptor extends ArrayAdapter<Entry> { 

    private TextView tvTitle, tvDate; 

    public EntryListAdaptor() { 
     super(MainActivity.this, R.layout.listview_item, entryList); 
    } 

    @Override 
    public View getView(int position, View convertView, ViewGroup parent) { 
     if (convertView == null) 
      convertView = LayoutInflater.from(MainActivity.this).inflate(R.layout.listview_item, null); 

     tvTitle = (TextView) convertView.findViewById(R.id.entryTitle); 
     tvDate = (TextView) convertView.findViewById(R.id.entryDate); 

     tvTitle.setText(entryList.get(position).getTitle()); 
     tvDate.setText(entryList.get(position).getDate()); 
     return convertView; 
    } 
    } 
}

activity_view.xml

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
android:orientation="vertical" android:layout_width="match_parent" 
android:layout_height="match_parent"> 

<LinearLayout 
    android:orientation="vertical" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:weightSum="1"> 

    <ImageView 
     android:layout_width="fill_parent" 
     android:layout_height="wrap_content" 
     android:id="@+id/ivImage" 
     android:layout_gravity="center" 
     android:src="@drawable/download" /> 

    <TextView 
     android:layout_width="367dp" 
     android:layout_height="wrap_content" 
     android:text="Testing" 
     android:id="@+id/lblTitle" 
     android:layout_marginTop="10dp" 
     android:textAppearance="@style/Base.TextAppearance.AppCompat.Medium" /> 

    <TextView 
     android:layout_width="fill_parent" 
     android:layout_height="222dp" 
     android:text="this is solely for the storyboard and may not be the  final interface of the application" 
     android:id="@+id/lblPassage" 
     android:layout_marginTop="10dp" 
     android:layout_weight="0.82" /> 

    <TextView 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:text="1/1/15" 
     android:id="@+id/lblDate2" 
     android:layout_gravity="right" /> 

    <LinearLayout 
     android:orientation="horizontal" 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content"> 

     <Button 
      android:layout_width="100dp" 
      android:layout_height="wrap_content" 
      android:text="Edit" 
      android:id="@+id/btnEdit" 
      android:layout_marginTop="10dp" 
      android:layout_gravity="left" /> 

     <Button 
      android:layout_width="100dp" 
      android:layout_height="wrap_content" 
      android:text="Back" 
      android:id="@+id/btnBack" 
      android:layout_gravity="right" 
      android:layout_marginTop="10dp" /> 
    </LinearLayout> 

    </LinearLayout> 

</LinearLayout>

Activity_View.Java

public class Activity_View extends AppCompatActivity { 

Button BackBtn = (Button) findViewById(R.id.btnBack); 
Button EditBtn = (Button) findViewById(R.id.btnEdit); 

@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    this.setContentView(R.layout.activity_view); 

    Bundle extras = getIntent().getExtras(); 
    String entryTitle = extras.getString("title"); 
    TextView title = (TextView) findViewById(R.id.lblTitle); 
    title.setText(entryTitle); 
    String entryPassage = extras.getString("passage"); 
    TextView passage = (TextView) findViewById(R.id.lblPassage); 
    passage.setText(entryPassage); 
    String entryDate = extras.getString("date"); 
    TextView date = (TextView) findViewById(R.id.lblDate2); 
    date.setText(entryDate); 

    BackBtn.setOnClickListener(new View.OnClickListener() { 
     @Override 
     public void onClick(View v) { 
      finish(); 
     } 
    }); 
    } 
}

Entry.Java

public class Entry { 

public String _title, _passage; 
public Uri _imageUri; 
public String _date; 
public int _id; 

public Entry (int id, String title, String passage, Uri imageUri, String date) { 
    _id = id; 
    _title = title; 
    _passage = passage; 
    _imageUri = imageUri; 
    _date = date; 
} 

public int getId() { return _id; } 
public String getTitle() { 
    return _title; 
} 
public String getPassage() { return _passage; } 
public Uri getImageUri() { return _imageUri; } 
public String getDate() { return _date; } 
}

DatabaseHandler.Java

public class DatabaseHandler extends SQLiteOpenHelper { 

private static final int DATABASE_VERSION = 1; 

public static final String DATABASE_NAME = "entriesManager", 
TABLE_ENTRIES = "entries", 
KEY_ID = "id", 
KEY_TITLE = "title", 
KEY_PASSAGE = "passage", 
KEY_IMAGEURI = "imageUri", 
KEY_DATE="date"; 


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

@Override 
public void onCreate(SQLiteDatabase db) { 
    db.execSQL("CREATE TABLE " + TABLE_ENTRIES + "(" + KEY_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " + KEY_TITLE + " TEXT," + KEY_PASSAGE + " TEXT," + KEY_IMAGEURI + " TEXT" + KEY_DATE + "TEXT)"); 
} 

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

    onCreate(db); 
} 

public void createEntry(Entry entry) { 
    SQLiteDatabase db = getWritableDatabase(); 

    ContentValues values = new ContentValues(); 


    values.put(KEY_ID,entry.getId()); 
    values.put(KEY_TITLE, entry.getTitle()); 
    values.put(KEY_PASSAGE, entry.getPassage()); 
    values.put(KEY_IMAGEURI, entry.getImageUri().toString()); 

    db.insert(TABLE_ENTRIES, null, values); 
    db.close(); 
} 

public Entry getEntry(int id) { 
    SQLiteDatabase db = getReadableDatabase(); 
    Cursor cursor = db.query(TABLE_ENTRIES, new String[] {KEY_ID, KEY_TITLE, KEY_PASSAGE, KEY_IMAGEURI}, KEY_ID + "=?", new String[] { String.valueOf(id) }, null, null, null, null); 

    if (cursor != null) 
     cursor.moveToFirst(); 

    Entry entry = new Entry(Integer.parseInt(cursor.getString(0)), cursor.getString(1), cursor.getString(2), Uri.parse(cursor.getString(3)), cursor.getString(4)); 
    db.close(); 
    cursor.close(); 
    return entry; 
} 

public void deleteEntry(Entry entry) { 
    SQLiteDatabase db = getWritableDatabase(); 
    db.delete(TABLE_ENTRIES, KEY_ID + "=?", new String[]{String.valueOf(entry.getId())}); 
    db.close(); 
} 

public int getEntriesCount() { 
    SQLiteDatabase db; 

    db = getReadableDatabase(); 
    Cursor cursor = db.rawQuery("SELECT * FROM " + TABLE_ENTRIES, null); 
    int count = cursor.getCount(); 
    db.close(); 
    cursor.close(); 

    return count; 
} 

public int updataEntry(Entry entry) { 
    SQLiteDatabase db = getWritableDatabase(); 

    ContentValues values = new ContentValues(); 
    values.put(KEY_TITLE, entry.getTitle()); 
    values.put(KEY_PASSAGE, entry.getPassage()); 
    values.put(KEY_IMAGEURI, entry.getImageUri().toString()); 

    return db.update(TABLE_ENTRIES, values, KEY_ID + "=?", new String[]{String.valueOf(entry.getId())}); 
} 

public List<Entry> getAllEntries() { 
    List<Entry> entries = new ArrayList<Entry>(); 

    SQLiteDatabase db = getWritableDatabase(); 
    Cursor cursor = db.rawQuery("SELECT * FROM " + TABLE_ENTRIES, null); 

    if (cursor.moveToFirst()) { 
     do { 
      Entry entry = new Entry(Integer.parseInt(cursor.getString(0)), cursor.getString(1), cursor.getString(2), Uri.parse(cursor.getString(3)), cursor.getString(4)); 
      entries.add(entry); 
     } 
     while (cursor.moveToNext()); 
    } 
    return entries; 
} 

public Cursor getData(int id) { 
    SQLiteDatabase db = this.getReadableDatabase(); 
    Cursor res = db.rawQuery("select * from Entries where KEY_ID = " + id, null); 
    res.moveToFirst(); 
    return res; 
} 
}

logcat的

12-09 06：16：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：進程：unipersonalinc.mypersonalediary，PID：5811 12-09 6點16分：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：java.lang.RuntimeException：無法實例化活動ComponentInfo {unipersonalinc.mypersonalediary/unipersonalinc.mypersonalediary.Activity_View}：java.lang.NullPointerException：嘗試調用虛擬方法'android。 view.View android.view.Window.findViewById（int）'null對象引用

6月12日至9日：16：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：在android.app.ActivityThread.performLaunchActivity（ActivityThread.java:2327）

6月12日至9日：16：55.140 5811 -5811/unipersonalinc.mypersonalediary E/AndroidRuntime：在android.app.ActivityThread.handleLaunchActivity（ActivityThread.java:2476）

6月12日至九日：16：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：在機器人.app.ActivityThread.-wrap11（ActivityThread.java）

12-09 06：16：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：at android.app.ActivityT hread $ H.handleMessage（ActivityThread.java:1344）

12-09 06:16:55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：at android.os.Handler.dispatchMessage（Handler.java:102）

12-09 06:16:55。140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：在android.os.Looper.loop（Looper.java:148）

6月12日至九日：16：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：在android.app.ActivityThread.main（ActivityThread.java:5417）

12-09 06：16：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：at java.lang.reflect.Method.invoke（Native法）

6月12日至9日：16：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit.java:726）

12-09 06：16：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：在com.android.internal.os.ZygoteInit.main（ZygoteInit.java:616）

12-09 6時十六：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：導致：java.lang.NullPointerException：試圖調用虛擬方法'android.view.View android.view.Window.findViewById（int）'對空引用

6月12日至9日：16：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：在android.app.Activity.findViewById（Activity.java:2090）

6月12日至9日：16：55.140 5811 -5811/unipersonalinc.mypersonalediary E/AndroidRuntime：at 。unipersonalinc.mypersonalediary.Activity_View（Activity_View.java:17）

六月12日至9日：16：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：在java.lang.Class.newInstance（本機方法）

六月12日至9日：16：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：在android.app.Instrumentation.newActivity（Instrumentation.java:1067）

六月12日至9日：16：55.140 5811- 5811/unipersonalinc.mypersonalediary E/AndroidRuntime：at android.app.ActivityThread.performLaunchActivity（ActivityThread.java:2317）

12-09 06 ：16：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：在android.app.ActivityThread.handleLaunchActivity（ActivityThread.java:2476）

6月12日至9日：16：55.140 5811-5811/unipersonalinc.mypersonalediaryë/AndroidRuntime：在android.app.ActivityThread.-wrap11（ActivityThread.java）

6月12日至9日：16：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：在android.app.ActivityThread $ H.handleMessage （ActivityThread.java:1344）

6月12日至9日：16：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：在android.os.Handler.dispatchMessage（Handler.java:102）

六月12日至9日：16：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：在android.os.Looper.loop（Looper.java:148）

六月12日至9日：16：55.140 5811 -5811/unipersonalinc.mypersonalediary E/AndroidRuntime：at android.app.ActivityThread.main（ActivityThread.java:5417） 12-09 06：16：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：at java.lang。 reflect.Method.invoke（本機方法）

6月12日至9日：16：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run（ZygoteInit。的java：726）

6月12日至9日：16：55.140 5811-5811/unipersonalinc.mypersonalediary E/AndroidRuntime：在com.android.internal.os.ZygoteInit.main（ZygoteInit.java:616）

來源

2015-12-09 souljin999

+0

logcat的嗎？ – Razgriz

+0

logcat？什麼是logcat？ – souljin999

+0

你的錯誤出現在哪裏。 – Razgriz

回答

0

錯誤在您的getData()方法中。與

Cursor res = db.rawQuery("select * from Entries where " + KEY_ID + " = " + id, null);

更換

Cursor res = db.rawQuery("select * from Entries where KEY_ID = " + id, null);

在你原來的方法你在哪裏試圖查找一個名爲KEY_ID列，它不存在，因爲KEY_ID是恆定的命名你的ID列。因此，您必須在SELECT聲明中插入值KEY_ID。

對於你的新問題，當你得到一個Cursor時，你必須迭代它的結果來獲得相應的數據，否則你會得到一個異常。爲了您的代碼，嘗試用

Cursor cursor = dbHandler.getData(searchId); 
if(cursor.moveToFirst()){ 
    String entryTitle = cursor.getString(cursor.getColumnIndex(dbHandler.KEY_TITLE)); 
    String entryPassage = cursor.getString(cursor.getColumnIndex(dbHandler.KEY_PASSAGE)); 
    String entryDate = cursor.getString(cursor.getColumnIndex(dbHandler.KEY_DATE)); 
}

更換

Cursor cursor = dbHandler.getData(searchId); 
String entryTitle = cursor.getString(cursor.getColumnIndex(dbHandler.KEY_TITLE)); 
String entryPassage = cursor.getString(cursor.getColumnIndex(dbHandler.KEY_PASSAGE)); 
String entryDate = cursor.getString(cursor.getColumnIndex(dbHandler.KEY_DATE));

而且在onItemClick回調檢查位置和searchId

int searchId = position - 1; 

Cursor cursor = dbHandler.getData(searchId);

此值應> = 0;

你的下一個問題，改變這種

public class Activity_View extends AppCompatActivity { 

Button BackBtn = (Button) findViewById(R.id.btnBack); 
Button EditBtn = (Button) findViewById(R.id.btnEdit); 

@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    this.setContentView(R.layout.activity_view); 
    ...

這樣：

public class Activity_View extends AppCompatActivity { 

Button backBtn; 
Button editBtn; 

@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    this.setContentView(R.layout.activity_view); 

    backBtn = (Button) findViewById(R.id.btnBack); 
    editBtn = (Button) findViewById(R.id.btnEdit); 
    ...

來源

2015-12-09 03:26:38

+0

android。 database.CursorIndexOutOfBoundsException：索引0請求，大小爲0，現在我得到這個錯誤 – souljin999

+0

請發佈您的Logcat –

+0

我編輯我的logcat文章 – souljin999

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