This is a conversion version from IGAS_UI, it use several views to display the container items, each view can have multi containers, each container can have multi rules, each rule will determine which bag slot will be shown on the container, it's easy to config, and smoothing to be used.:

You can open/close the bag container during combat or use esc to close it without taint.

You can click the ? to open the view rule manager.

You can click Add View to add more bag views:

add view

Click the view you want change, use the add container to add a new container:

add container

Each container can have multi rules set, each set contains several rule, it a bag slot match any of the rule set, it'll be contained in this container.

add rules

You can click the rule-set to modify them, you can click to set a text, the the bag slot's gametooltip text must match it, you can drag item into it, so you can choose In Item List rule.

rule set

Click the existed rule to remove, or click the add rule to add other rules, the bag slot must match all the rules in set.

add rule

BagView