2

我收到此错误

10-11 13:58:46.713: E/AndroidRuntime(29407): FATAL EXCEPTION: AsyncTask #2
10-11 13:58:46.713: E/AndroidRuntime(29407): java.lang.RuntimeException: An error occured while executing doInBackground()
10-11 13:58:46.713: E/AndroidRuntime(29407):    at android.os.AsyncTask$3.done(AsyncTask.java:299)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at java.util.concurrent.FutureTask.run(FutureTask.java:137)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at java.lang.Thread.run(Thread.java:856)
10-11 13:58:46.713: E/AndroidRuntime(29407): Caused by: java.lang.IllegalStateException: attempt to re-open an already-closed object: SQLiteDatabase: /data/data/com.philly.philly/databases/PhillyORM.db
10-11 13:58:46.713: E/AndroidRuntime(29407):    at android.database.sqlite.SQLiteClosable.acquireReference(SQLiteClosable.java:55)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1310)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at android.database.sqlite.SQLiteDatabase.rawQuery(SQLiteDatabase.java:1253)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at com.j256.ormlite.android.AndroidCompiledStatement.getCursor(AndroidCompiledStatement.java:154)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at com.j256.ormlite.android.AndroidCompiledStatement.runQuery(AndroidCompiledStatement.java:57)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at com.j256.ormlite.stmt.SelectIterator.<init>(SelectIterator.java:55)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at com.j256.ormlite.stmt.StatementExecutor.buildIterator(StatementExecutor.java:206)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at com.j256.ormlite.stmt.StatementExecutor.query(StatementExecutor.java:155)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at com.j256.ormlite.dao.BaseDaoImpl.query(BaseDaoImpl.java:261)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at com.j256.ormlite.stmt.QueryBuilder.query(QueryBuilder.java:262)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at com.j256.ormlite.stmt.Where.query(Where.java:482)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at com.j256.ormlite.dao.BaseDaoImpl.queryForEq(BaseDaoImpl.java:241)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at com.philly.philly.Repository.saveOrUpdateKontext(Repository.java:180)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at com.philly.philly.PostListActivity$LoadPostsTask.doInBackground(PostListActivity.java:161)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at com.philly.philly.PostListActivity$LoadPostsTask.doInBackground(PostListActivity.java:1)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at android.os.AsyncTask$2.call(AsyncTask.java:287)
10-11 13:58:46.713: E/AndroidRuntime(29407):    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
10-11 13:58:46.713: E/AndroidRuntime(29407):    ... 5 more

我相信关键部分是10-11 13:58:46.713: E/AndroidRuntime(29407): Caused by: java.lang.IllegalStateException: attempt to re-open an already-closed object: SQLiteDatabase: /data/data/com.philly.philly/databases/PhillyORM.db

当我在异步任务从远程服务器检索数据时旋转屏幕时会发生这种情况。

我假设正在发生的是请求正在返回并尝试写入数据库，但启动任务的活动已被破坏并重新启动。

如果您需要查看我的代码，我会添加它，但我认为仅从错误消息和我的描述来看，这个问题的根源实际上可能很清楚。

我只是在寻找如何在检索远程数据和使用 ORMLite 写入本地数据库时正确处理屏幕旋转。也许我应该使用服务而不是异步任务？

提前致谢。

4

2 回答 2

1

您的活动可能正在轮换关闭数据库。我的建议是使用 AsyncTaskLoader，它会自行处理旋转。http://developer.android.com/guide/components/loaders.html

我从经验中学到的一个技巧是拥有一个单例 DB 对象，它只会在应用程序的整个生命周期中打开一次……当应用程序终止时，该对象会自动关闭。

于 2012-10-12T12:21:38.847 回答
0

您最好使用服务来处理数据库。当您旋转屏幕时，所有组件的当前布局都被破坏，并使用新的方向布局（将有其他组件）构建新布局。如果您不真正使用它，您还可以选择阻止屏幕旋转。

于 2012-10-11T18:31:55.773 回答