getLastVisiblePosition returning -1
I'm having a problem with my ListView
(using CursorAdapte
r). When I call getListView().getLastVisiblePosition()
I am receiving -1
. This is a problem since my list is populated with items. Additionally, getListView().getFirstVisiblePosition()
always returns 0, no matter where I am scrolled on the list. 开发者_StackOverflow社区 Any ideas?
It has something to do with startManagingCursor
@Override
public void changeCursor(Cursor cursor) {
super.changeCursor(cursor);
MyActivity.this.mCursor = cursor;
//startManagingCursor(MyActivity.this.mCursor);
}
If I comment out startManagingCursor, everything works fine. I've also tried adding stopManagingCursor()
before changing the Cursor
and still have the same problem.
This is because the moment you call getListView().getLastVisiblePosition() the listview is not rendered. You can add the call to the view's message queue like this:
listview.post(new Runnable() {
public void run() {
listview.getLastVisiblePosition();
}
});
Even I faced the same problem. The thing is that, getLastVisiblePosition() works only when you are in the first element of your listview and for the rest you will get null being returned. So what I did is that, I made a small calculation to find out the exact view position which I have mentioned below,
int LastPos=(mylist.getLastVisiblePosition()-mylist.getFirstVisiblePosition());
This returns the exact last position without a doubt.
My guess is that your getItem(int position)
and getItemId(int position)
methods aren't defined correctly in your adapter.
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