[CONNECT C++] ViewGroups and ViewInfo

Question

When we do something like this (taken from SDK ..\Visualization\DisplayStyleExample )... 
 ViewGroupCollectionCR viewGroups = dgnFile->GetViewGroups();
 ViewGroupPtr viewGroup = viewGroups.GetActiveP();
 if (!viewGroup.IsValid())
 return;
 int viewIndex = 0;
 ViewInfoR viewInfo = viewGroup->GetViewInfoR (viewIndex);

Is the active ViewGroup always available when MicroStation has a DGN file open? 
 Do all eight ViewInfo instances exist even when some views are closed?

Brien Bastings · Accepted Answer

> Is the active ViewGroup always available when MicroStation has a DGN file open? 
 It should be, the active view group is made active when a file is opened...but you should always check that you have a valid ptr... 
 > Do all eight ViewInfo instances exist even when some views are closed? 
 Closed or open, there will always be a ViewInfo for views 0-7, that's why it can return a reference instead of a pointer (the on/off state is a ViewFlag). 
 That said, it's possible for a ViewGroup to not define all 8 views (usually see this w/DWG files), information about whether a view is defined comes from the ViewPortInfo. 
 -B

[CONNECT C++] ViewGroups and ViewInfo

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