问题
In my application I have a listview. I get my data with a query from a SQLiteDatabase. When I get the data from the db I get this error:
It occurs when I go from line 20 to 21.
I tried placing cursor.deactivate() and cursor.close() on regel 50. But with no result. Anyone knows why I get this error and how to solve it? Thanks :)
回答1:
You have to close the cursor before the database. Put your code in a try
/ catch
block and in a finally
block, close the cursor and then close the database:
try {
db = ...
} catch(Exception ex) {
// Log the exception's message or whatever you like
} finally {
try {
if( cursor != null && !cursor.isClosed())
cursor.close();
if( db.isOpen() )
db.close();
} catch(Exception ex) {}
}
Closing sequence matters a lot while doing IO with DB or Content Providers. For more information refer this link
回答2:
to find such problems just enable StrictMode for Debug Version like that:
public void onCreate() {
if (DEVELOPER_MODE) {
StrictMode.setThreadPolicy(new StrictMode.ThreadPolicy.Builder()
.detectDiskReads()
.detectDiskWrites()
.detectNetwork() // or .detectAll() for all detectable problems
.penaltyLog()
.build());
StrictMode.setVmPolicy(new StrictMode.VmPolicy.Builder()
.detectLeakedSqlLiteObjects()
.detectLeakedClosableObjects()
.penaltyLog()
.penaltyDeath()
.build());
}
super.onCreate();
}
more information @ http://developer.android.com/reference/android/os/StrictMode.html
all the best,
回答3:
Always, remember to close the cursor by calling cursor.close() before closing the database. That should fix your problem.
回答4:
let the activity manage the cursor lifecycly by using startManagingCursor(c)
and it will be fine.
来源:https://stackoverflow.com/questions/10434378/cursor-finalized-without-prior-close-android