[CONNECT C++] DgnElementSetTool: Query Elements in Reference Attachments

I answered my own question.  The solution is to add mdlLocate_allowLocked() in the _OnPostInstall event...

void    QueryTool::_OnPostInstall ()
{
    //Enable picking of elements
    _BeginPickElements ();
    mdlAutoLocate_setComplexComponentMode (ComponentMode::Innermost); //NOTE: Must be called after BeginPickElements!
    __super::_OnPostInstall ();
    //Permit location of elements in references -- not required: use the overridden method mentioned below
    mdlLocate_allowLocked ();
}

Note that mdlLocate_allowLocked() must be called after __super::_OnPostInstall ().

I was initially put off using mdlLocate_allowLocked() because of this note in MicroStationAPI help...

Obsolete enum; here only to help convert code. 

Is that note irrelevant?

Yongan's response below is a better solution.  It uses the DgnElementSetTool base class methods rather than introduce MDL functions.

Hello Jon,

Apologize a long time not in this English forum because there is always a lot Chinese posts on ChinaFirst Programming forum.

A formal and simpler approach to do this is to override _IsModifiedOriginal member function and return false.

virtual bool _IsModifyOriginal () override {return false;}

Unknown said:

Apologize a long time not in this English forum

Good to hear from you again!

Unknown said:

virtual bool _IsModifyOriginal () override {return false;}

Thanks!  The documentation is a little ambiguous about that method  8-)

Hello Jon,

It works for me. As an example, after I add this line in C:\Program Files\Bentley\MicroStationCONNECTSDK\examples\Elements\exampletool\ExampleModifyTool.cpp as below, it can accept linestring in reference.

Maybe other staffs  in your code prevents it work.

Unknown said:

Maybe other staffs stuff  in your code prevents it work

Yes!  I have a base class that does exactly what you say.  Unfortunately I had a derived class that did something different.  In response to your hint I have adopted William Bushnell Stout's maxim: simplicate and add lightness. Now, it all works fine.

Good to know your code works fine and thank you pointing me out my English word error (staff or stuff).

In Chinese, there are a lots of very similiar words as well.For example,戌 and 戍, 士 and 土. :)

Good to know your code works fine and thank you pointing me out my English word error (staff or stuff).

In Chinese, there are a lots of very similiar words as well.For example,戌 and 戍, 士 and 土. :)

Just wanted to add a couple things that probably aren't obvious.

DgnElementSetTool establishes the locate criteria in _SetLocateCriteria (which is called from _BeginPickElements for pick and _BuildAgenda for fences and selection sets). This is the place to add any tool specific locate criteria as opposed to _OnPostInstall.

Returning false from _IsModifyOriginal allows locked/reference elements to be selected as it puts DgnElementSetTool into copy mode. For a query only tool this can have the undesirable side-effect of cloning styles, etc. from the source to the destination.

To avoid this, a query tool should override _OnPreElementModify. If you return SUCCESS without calling super, _OnElementModify will still be called if that's were you want to have your logic to extract information from the selected elements.

virtual StatusInt _OnElementModify (EditElementHandleR eeh) override {return ERROR;} // Query tool doesn't modify elements...
virtual StatusInt _OnPreElementModify (EditElementHandleR eeh) override {return SUCCESS;} // Don't copy styles, etc. from reference to active...
virtual bool _IsModifyOriginal () override {return false;} // Allow selection of locked/reference elements

HTH

-B