Android CursorLoader和acquireUnstableProvider的异常原因是什么？

主要活动：

`

`

日志：

09-13 06:50:08.261: E/AndroidRuntime(11105): FATAL EXCEPTION: AsyncTask #1
09-13 06:50:08.261: E/AndroidRuntime(11105): java.lang.RuntimeException: An error occured while executing doInBackground()
09-13 06:50:08.261: E/AndroidRuntime(11105):    at android.os.AsyncTask$3.done(AsyncTask.java:299)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at java.util.concurrent.FutureTask.run(FutureTask.java:137)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at java.lang.Thread.run(Thread.java:856)
09-13 06:50:08.261: E/AndroidRuntime(11105): Caused by: java.lang.NullPointerException
09-13 06:50:08.261: E/AndroidRuntime(11105):    at android.content.ContentResolver.acquireUnstableProvider(ContentResolver.java:1094)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at android.content.ContentResolver.query(ContentResolver.java:354)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at android.content.CursorLoader.loadInBackground(CursorLoader.java:65)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at android.content.CursorLoader.loadInBackground(CursorLoader.java:43)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at android.content.AsyncTaskLoader.onLoadInBackground(AsyncTaskLoader.java:301)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at android.content.AsyncTaskLoader$LoadTask.doInBackground(AsyncTaskLoader.java:68)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at android.content.AsyncTaskLoader$LoadTask.doInBackground(AsyncTaskLoader.java:56)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at android.os.AsyncTask$2.call(AsyncTask.java:287)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
09-13 06:50:08.261: E/AndroidRuntime(11105):    ... 4 more

我使用

CursorLoader

从数据库中获取数据，并使用BaseAdapter将数据放入listView

谁能告诉我我的代码出了什么问题？我不知道这个问题。

---

谢谢您的帮助。

在

MyCursorLoader

编辑

doInBackGround

到

doInBackGround

请编辑完整的日志并粘贴到您的问题中。尝试阅读这是一件痛苦的事，它似乎没有什么。我粘贴了LogCat，谢谢。我尝试阅读LogCat，但我不知道我的问题……我建议你将你的问题标题重命名为包括“CursorLoader”和“acquireUnstableProvider”-你的CursorLoader的第65行和第43行是什么？这里可能有线索……我创建了

MyCurSorLoader.class

，但我没有创建

CursorLoader

，所以我不知道

CursorLoader

…在活动中有DatabaseHelper引用，在CursorLoader中也有它们。我认为您的活动不应该引用DatabaseHelper。游标加载程序可能应该封装DatabaseHelper。试着逐行调试它，看看NullPointerException发生在哪里。@IwillnotexistIdonotexist：他在回答自己的问题，这在当时是很受鼓励的。话虽如此，OP最好能在答案中增加一些实质性内容

public class MyCursorLoader extends CursorLoader {

private DataBaseHelper dh = null;
private SQLiteDatabase db;
private Context context;
private String columns[], tableName;

public MyCursorLoader(Context context) {
    super(context);
    this.context = context;
    // TODO Auto-generated constructor stub
}

public Cursor loadInBackGround() {
    dh = new DataBaseHelper(context);
    db = dh.getReadableDatabase();

    tableName = dh.getTableName();

    int i = dh.getCount();
    columns = new String[i];
    for (int j = 0; j < i; j++) {
        columns[j] = dh.getColumns(j);
    }

    Cursor cursor = db.query(tableName, columns, null, null, null, null,
            null);
    return cursor;
}
}

public class DataBaseHelper extends SQLiteOpenHelper {

private final static int dbVersion = 1;
private final static String dbName = "PhotoerDataBase";
private final static String tableName = "AlbumTable";
private String tableColumns[] = { "_id", "Title", "Content", "Date",
        "Location", "Cover" };

public DataBaseHelper(Context context) {
    super(context, dbName, null, dbVersion);
    // TODO Auto-generated constructor stub
}

@Override
public void onCreate(SQLiteDatabase db) {
    // TODO Auto-generated method stub
    final String sqlCommand = "CREATE TABLE IF NOT EXISTS " + tableName
            + "( _id INTEGER PRIMARY KEY AUTOINCREMENT, " + tableColumns[1]
            + " TEXT, " + tableColumns[2] + " TEXT, " + tableColumns[3]
            + " TEXT, " + tableColumns[4] + " TEXT, " + tableColumns[5] + " TEXT);";
    db.execSQL(sqlCommand);
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    // TODO Auto-generated method stub
    final String sqlCommand = "DROP TABLE IF EXISTS " + tableName;
    db.execSQL(sqlCommand);
    onCreate(db);
}

public int getCount() {
    return tableColumns.length;// return 5
}

public String getColumns(int index) {
    return tableColumns[index];
}

public String getTableName() {
    return tableName;
}

}

09-13 06:50:08.261: E/AndroidRuntime(11105): FATAL EXCEPTION: AsyncTask #1
09-13 06:50:08.261: E/AndroidRuntime(11105): java.lang.RuntimeException: An error occured while executing doInBackground()
09-13 06:50:08.261: E/AndroidRuntime(11105):    at android.os.AsyncTask$3.done(AsyncTask.java:299)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at java.util.concurrent.FutureTask.run(FutureTask.java:137)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at java.lang.Thread.run(Thread.java:856)
09-13 06:50:08.261: E/AndroidRuntime(11105): Caused by: java.lang.NullPointerException
09-13 06:50:08.261: E/AndroidRuntime(11105):    at android.content.ContentResolver.acquireUnstableProvider(ContentResolver.java:1094)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at android.content.ContentResolver.query(ContentResolver.java:354)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at android.content.CursorLoader.loadInBackground(CursorLoader.java:65)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at android.content.CursorLoader.loadInBackground(CursorLoader.java:43)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at android.content.AsyncTaskLoader.onLoadInBackground(AsyncTaskLoader.java:301)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at android.content.AsyncTaskLoader$LoadTask.doInBackground(AsyncTaskLoader.java:68)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at android.content.AsyncTaskLoader$LoadTask.doInBackground(AsyncTaskLoader.java:56)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at android.os.AsyncTask$2.call(AsyncTask.java:287)
09-13 06:50:08.261: E/AndroidRuntime(11105):    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
09-13 06:50:08.261: E/AndroidRuntime(11105):    ... 4 more