as hide/show work with selection you should select everything then CTRL the object to keep, then hide.
there are some other option if you are talking about instances in assembly and not geometry, you could inverse selection.
in 3DX you would do a keep.
Eric N. indocti discant et ament meminisse periti
left mouse down, drag a rectangle and release left mouse...... everything becomes orange. left click+ctrl on particular part called cylinder.Catpart, then hit hide/show icon at bottom toolbar, everything disappears, including cylinder
thanks for the complete description of your action. This help me understand what is wrong.
When you select with a trap in 3D you actually select geometrical elements, the when you CTRL select the instance or the part it does actually add this element to the selection. Hide will just hide all. Normal.
I was thinking select all in 3D then CTRL select in 3D the geometrical element - this will actually unselect - then finally Hide.
For you I will select the part properties and select no pick-able, then trap select 3D. your part's geometrical elements should not be selected, then Hide. Go back to part property and make it pick-able again.
I also use filter sometime. As default has no layer, I select the body I want and put it on layer 100. then apply filter to see only layer 100.
The cool stuff is that I can select in tree other element and bring them visible by putting them on layer 100.
Hope this help
Eric N. indocti discant et ament meminisse periti
You can also enable the 'Products Selection" selection filter and drag a box around the elements in the geometry. Using this filter it will be just as though you selected the Instances via the Specification Tree.