Enable Edit Mode first (see Edit Mode).

You can hide a class by making a right-click on the class and use Hide.

Now the class has disappeared.

If you use Custom Classes (see Create Custom Class) then you can hide them as well.

And as with regular P&ID classes, the Custom Classes disappear too.

At the end of the process disable the Edit Mode again (see Edit Mode).
 

If you want to see the class again, you use the toggle button at the top.

Now you see the hidden class in a greyed out style. Also the symbol and the symbol's class or display name shows greyed out.

If you select a node which includes the hidden class, the class, symbol and symbol's name shows greyed out too.

How opaque the texts and symbol should appear can be set in the PlantExpressTools Settings (see SymbolsPalette).

To hide the hidden classes again, you click on the toggle button again.

Now the class and the symbol are hidden again.

Instead of using the toggle button, you can also use the context menu and use Show all classes, including the hidden ones.

And to hide the hidden classes again you use Hide all hidden marked classes.

And now they are hidden again.

Enable Edit Mode first (see Edit Mode).

To change the status of a class you use Show.

Now the class, symbol and symbol's name isn't greyed out anymore.

At the end of the process disable the Edit Mode again (see Edit Mode).
 

Enable Edit Mode first (see Edit Mode).

Besides hiding a class you can also hide a whole node with multiple classes. You also use Hide.

Now the whole node and classes are hidden.

At the end of the process disable the Edit Mode again (see Edit Mode).
 

As before with the hiding of classes, you can either use the toggle button or the context menu with Show all classes, including the hidden ones.

Now the node and the classes as well as all symbols and symbol's names are greyed out.

With the toggle button or the context menu Hide all hidden marked classes you can hide the node and classes again.

Now they are hidden again.

Enable Edit Mode first (see Edit Mode).

Use Show if the node marked as hidden should not be hidden anymore.

Now everything is back to normal.

At the end of the process disable the Edit Mode again (see Edit Mode).

Enable Edit Mode first (see Edit Mode).

Hidden classes or nodes also have an effect on the categories.

Here is an example of the Lines category where you see all Pipe Line Segments and signal Line Segments.

Now we hide the Signal Line Segments class.

The class is hidden now.

When we switch back to the category view, we see, that the Signal Line Segments are hidden as well.

if we use the toggle button to show the hidden classes...

...we will see the Signal Line Segments marked as hidden greyed out too.

At the end of the process disable the Edit Mode again (see Edit Mode).
 

Enable Edit Mode first (see Edit Mode).

The same way you can hide and show P&ID classes you can also hide and show Custom Classes and Folder Links.

Now the Custom Class is hidden.

The same with Folder Links.

And gone.

With the toggle button above the tree...

... the Customer Classes and Folder Links are shown again in a greyed out style.

To change the state of the Folder Links you use Show.

The same for Custom Classes.

Now everything is shown again and won't be hidden anymore when using the toggle button.

At the end of the process disable the Edit Mode again (see Edit Mode).