[CONNECT C++] IDgnECTypeAdapter::GetStandardValues

What are you trying to accomplish, Jon?

Unknown said:

What are you trying to accomplish?

Following your previous hints, I'm exploring how to get a custom display string from a standard element property.  For example, a closed element seems to belong to an EC AreaClass in the MstnPropertyFormatter schema. ECProperty Units has a list of StandardValues including Use Active Master Units, Acres and others.  How do I obtain a string that measures a closed element in, say, Acres?

I find it rather easy to become lost in the forest of DgnECTypeAdapter, ECEnabler, DgnECInstance, DgnECTypeAdapterContext and ECProperty.

MstnPropertyFormatter:AreaClass has nothing to do with closed elements. That schema is all about formatting property values.
Closed elements are represented by subclasses of BaseElementSchema:MstnClosedBoundary.

Create an ECInstance of AreaClass, set its Units property to -3, and pass it to TextField (or to IDgnECTypeAdapter, if you're doing your own formatting).

Unknown said:

Create an ECInstance of AreaClass

I'm stumped.  I think that I need a DgnECInstanceEnabler in order to create an ECInstance.  Here's what I have so far...

if (TextPropertyManager::GetMstnPropertyFormatterSchema (formatSchema)) // help function
{
  ECN::ECClassCP  formatClass	= formatSchema->GetClassCP (L"AreaClass");
  //trace: got EC Class 'AreaClass' Display Label 'Closed Elements'
  const bool&     IncludeBaseClasses	{ true };
  ECPropertyP     prop	= formatClass->GetPropertyP (L"Units", IncludeBaseClasses);
  //trace: Schema 'MstnPropertyFormatter' Class 'AreaClass' has property 'Units'
  DgnECManagerR   manager		= Bentley::DgnPlatform::DgnECManager::GetManager();
  DgnECInstanceEnablerP formatEnabler = manager.ObtainInstanceEnabler  (*formatClass, *GetActiveDgnFile ());
  // formatEnable == nullptr
}

What have I missed?

Unknown said:

Create an ECInstance of AreaClass

I'm stumped.  I think that I need a DgnECInstanceEnabler in order to create an ECInstance.  Here's what I have so far...

if (TextPropertyManager::GetMstnPropertyFormatterSchema (formatSchema)) // help function
{
  ECN::ECClassCP  formatClass	= formatSchema->GetClassCP (L"AreaClass");
  //trace: got EC Class 'AreaClass' Display Label 'Closed Elements'
  const bool&     IncludeBaseClasses	{ true };
  ECPropertyP     prop	= formatClass->GetPropertyP (L"Units", IncludeBaseClasses);
  //trace: Schema 'MstnPropertyFormatter' Class 'AreaClass' has property 'Units'
  DgnECManagerR   manager		= Bentley::DgnPlatform::DgnECManager::GetManager();
  DgnECInstanceEnablerP formatEnabler = manager.ObtainInstanceEnabler  (*formatClass, *GetActiveDgnFile ());
  // formatEnable == nullptr
}

What have I missed?

Jon,

DgnECInstanceEnabler is used for creating DgnECInstances - i.e., ECInstances that are to be persisted into the DgnFile.
All you need is an IECInstance.

You could take the easy road I previously suggested, which is to obtain the IDgnECTypeAdapter for the property/type of interest, and call its CreateDefaultFormatter() function which returns an IECInstance of the appropriate class.

Or, you could use formatClass->GetDefaultStandaloneEnabler()->CreateInstance().

I assume your call to GetPropertyP("Units",...) is strictly for debugging...there should be no need to look up ECProperties simply to set property values in an IECInstance.

Another pass through the IDgnECTypeAdapter/IECTypeAdapter API documentation may be useful.

Regards,
Paul

Unknown said:

All you need is an IECInstance...

Finally I arrived at my destination...

An IECInstance instance is created from ECClass AreaClass and its Units and Accuracy properties set to show two decimal points and Acres measurement unit.  The resulting formatter instance is passed to TextField::CreateForElement to make a formatted text field.

Thanks for all your help and guidance!

Hi Jon,  I see u have a lot comments/post about the unit, I meet a similar issue from my side, which i just want to get the unit display string,

 https://communities.bentley.com/products/programming/microstation_programming/f/microstation-programming---forum/179320/how-to-get-the-display-property-value-for-ce-version-10-07-with-c

can u help me out there? 

thanks,

Rick