Why do ListView items not grow to wrap their content?

Try this: http://www.java2s.com/Code/Android/UI/setListViewHeightBasedOnChildren.htm

public class Utils {

    public static void setListViewHeightBasedOnChildren(ListView listView) {
        ListAdapter listAdapter = listView.getAdapter(); 
        if (listAdapter == null) {
            // pre-condition
            return;
        }

        int totalHeight = 0;
        for (int i = 0; i < listAdapter.getCount(); i++) {
            View listItem = listAdapter.getView(i, null, listView);
            listItem.measure(0, 0);
            totalHeight += listItem.getMeasuredHeight();
        }

        ViewGroup.LayoutParams params = listView.getLayoutParams();
        params.height = totalHeight + (listView.getDividerHeight() * (listAdapter.getCount() - 1));
        listView.setLayoutParams(params);
        listView.requestLayout();
    }     
}

I managed to fix this, but I don't understand why.

As I mentioned, I had set the layout_height of the list item layout to wrap_content (since fill_parent is meaningless here, considering that a ListView is indefinitely tall).

However, I had set the layout_height of all views inside that layout to fill_parent. The problem disappeared when setting them to wrap_content instead.

This raises two other questions:

1) What are the semantics of a view asking to fill_parent, when the parent wraps_content? Which size request takes precedence?

2) How would I ever make a view fill a list item if fill_parent apparently doesn't work?

Thanks for your input guys.