Collapsing a branch


You may have noticed that when you collapse a branch in Explorer and then expand it again later, the effect is that any child branches that were expanded earlier are again expanded. Although, this is mostly helpful, sometimes you want to be able to traverse the outline one level at a time so that you can get the bigger picture before you go on to the detail. We can achieve this programatically by collapsing the main item and then collapsing all its children recursively. Heres the code.
 
// CollapseBranch       - Collapses a branch completely
// hti                  -  Handle of the tree item to collapse
void CTreeCtrlX::CollapseBranch( HTREEITEM hti)
{
        if( ItemHasChildren( hti ) ){
                Expand( hti, TVE_COLLAPSE );
                hti = GetChildItem( hti );
                do{
                        CollapseBranch( hti );
                }while( (hti = GetNextSiblingItem( hti )) != NULL );
        }
}