Question

Is it possible to save and restore the state (which items are collapsed and which not) of an ExpandableListView in Android?

If it is possible, how can I do that?

Can I access the ExpandableListView in onPause() / onResume() and how?

Answer 1

I iterate through the groups and save the state of them all:

int numberOfGroups = MyExpandableListViewAdapter.getGroupCount();
boolean[] groupExpandedArray = new boolean[numberOfGroups];
  for (int i=0;i<numberOfGroups;i++)
    groupExpandedArray[i] = MyExpandableListView.isGroupExpanded(i);

Then for restore the state:

for (int i=0;i<groupExpandedArray.length;i++)
  if (groupExpandedArray[i] == true)
    MyExpandableListView.expandGroup(i);

I don’t understand what you mean by how to access the ListView in onPause() / onResume(), it should be accessible from there if you store the ListView object as a member of the activity class.