As in title: I would like to know how to get list (array) of all currently displayed items in my AdapterView.
Why? Objects that are displayed in my AdapterView require releasing a listener after user closes AdapterView. I need to do it in order to optimize my app.
Or is there any method (that I could override) which is executed on views' destruction?
AdapterView is a ViewGroup that displays items loaded into an adapter. The most common type of adapter comes from an array-based data source.
To get which item was selected, there is a method of the ListView called getItemAtPosition. Add this line to your OnItemClick method: String itemValue = (String) theListView. getItemAtPosition( position );
implements OnScrollListener
public class NewsCategoryDC extends Activity implements OnScrollListener {
and set OnScrollListener in listView
listView.setOnScrollListener(NewsCategoryDC.this);
and you can get first and last visible rows
@Override
public void onScroll(AbsListView view, int firstVisibleItem,int visibleItemCount, int totalItemCount) {
firstVisibleRow = listView.getFirstVisiblePosition();
lastVisibleRow = listView.getLastVisiblePosition();
/*Now you get the first and last visible rows, and you easily get the rows from first to last visible row and allocate resources to visible rows or deallocate resources to rows except visible rows..,.*/
}
@Override
public void onScrollStateChanged(AbsListView view, int scrollState) {}
TRY THIS..,.
and if some other best way you got please post, this is very useful and good question..,.
Thanks..,.
EDIT............................
add code in onScroll() method
@Override
public void onScroll(AbsListView view, int firstVisibleItem,int visibleItemCount, int totalItemCount) {
int firstVisibleRow = listView.getFirstVisiblePosition();
int lastVisibleRow = listView.getLastVisiblePosition();
for(int i=firstVisibleRow;i<=lastVisibleRow;i++)
{
//Write your code here(allocation/deallocation/store in array etc.)
System.out.println(i + "=" + listView.getItemAtPosition(i));
}
}
As small hint:
If you want to get all elements which are fully visible ( --> expect those, who are on the bottom or top and are nearly out of screen) you should look at this post :
See only fully visible ListView-Items
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