Welcome to the forum. It appears that a sketch is showing with everything else hidden. You might try clicking on the bodies and see if the icon for Show Bodies is available. If it's not, and the Hide Bodies icon is available, click it, then RMB again and Show.
Also, make sure you don't have a sketch active.
If this doesn't work can you post your part? Click on "Use advanced editor" at the top right of this screen to post files.
They are simply hidden, and clock "show" turns all on.
But I don't know why even if the part is made of several smaller objects, click content menu's "show" or "hide" would instantly apply to all objects. So is this a "global" command for all objects or "local" command that is applicable to individual objects?
Qi Lu wrote:
But I don't know why even if the part is made of several smaller objects, click content menu's "show" or "hide" would instantly apply to all objects.
Possibly when one or more of the bodies were created the box was checked for "Merge bodies", so that you now have one body instead of several.
Show or Hide can be applied at several different levels. I don't actually have SW running right now, so this is coming from memory and may not be completely correct. If you have a single body part, then right clicking on the features in the tree will bring up the eyeglasses that allow you to show or hide the part. If you have a multi-body part, then you will normally get a Solid Body folder. You can right click on the folder to show or hide all of the bodies at once. (Although I don't think it toggles the display of bodies that you have individually hidden.) You can click on individual bodies to hide or show them. You can do the same on parts and subassemblies in your assemblies. You can hide a subassembly or a single part in a subassembly.
There are also some View settings that you can change. So you can hide or show individual sketches by right clicking on them in the Feature Manager, but if you have Sketches turned off in the View menu, then none of them will show up. Similarly there is a Hide All Types selection in the View menu that hides everything in the list of types that the View menu controls.
Sorry for my late reply. Now finally got familiar with the feature, thanks.