问题描述
我有一个数据库，如下所示：
I have a database as follows:
------------------------------
BOOK NAME | BOOK FORMAT | COUNT |
------------------------------
Android | HTML | 1
WPF | PDF | 10
Symbian | PS | 2
Windows | HTML | 2
我显示这个数据库用户通过利用CustomSimpleCursorAdapter的。
I am showing this database to the userby making use of a CustomSimpleCursorAdapter.
CustomSimpleCursorAdapter extends SimpleCursorAdapter
实现的可筛选
implements Filterable
与 getView（）＆放大器; runQueryonBackgroundThread（）被覆盖。
书籍的网格视图中正常显示。
with getView() & runQueryonBackgroundThread() being overriden.
The Grid view of books is properly shown.
用户有以下选项：
HTML | PDF | PS |删除
HTML | PDF | PS | DELETE
Constraint: BOOK FORMAT
[HTML - 1, PDF - 2, PS - 3]
当用户presses HTML菜单选项，使用HTML书籍型已被示出。
When the user presses HTML menu option, the books with HTMLtype has to be shown.
MenuOption处理器（）里面，我写如下：
inside MenuOption handler(), I wrote as follows:
adapter.getFilter().filter("1");
runQueryonBackgroundThread() {
if(mCursor != null)
mCursor.close();
mCursor = query(using the constraint)
return mCursor;
}
这约束达到我重写 runQueryonBackgroundThread（）方法。但它没有更新网格视图并抛出异常。
This constraint reaching my overriden runQueryonBackgroundThread()method. But its not updating the grid view and throws an exception.
FILTER：android.view.ViewRoot $ CalledFromWrongThreadException：只有 创建一个视图层次可以触摸的意见原帖
请帮我。
推荐答案
我想你已经搞砸了事情有点。其实 SimpleCursorAdapter 已经实现了可筛选，所以没有必要重新实现它。相反，在你的 ListActivity 使用水木清华这样的：
I think you've messed up things a bit. Actually SimpleCursorAdapter already implements Filterable, so there's no need to reimplement it. Instead in your ListActivity use smth like this:
private void filterList(CharSequence constraint) {
final YourListCursorAdapter adapter =
(YourListCursorAdapter) getListAdapter();
final Cursor oldCursor = adapter.getCursor();
adapter.setFilterQueryProvider(filterQueryProvider);
adapter.getFilter().filter(constraint, new FilterListener() {
public void onFilterComplete(int count) {
// assuming your activity manages the Cursor
// (which is a recommended way)
stopManagingCursor(oldCursor);
final Cursor newCursor = adapter.getCursor();
startManagingCursor(newCursor);
// safely close the oldCursor
if (oldCursor != null && !oldCursor.isClosed()) {
oldCursor.close();
}
}
});
}
private FilterQueryProvider filterQueryProvider = new FilterQueryProvider() {
public Cursor runQuery(CharSequence constraint) {
// assuming you have your custom DBHelper instance
// ready to execute the DB request
return dbHelper.getListCursor(constraint);
}
};
这篇关于FilterQueryProvider，过滤器和ListView的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！