delite/activationTracker is a utility module that is used to track and manage active widgets on a page.

At any point in time there is a set of (for lack of a better word) "active" or "focused" widgets, meaning the currently focused widget and that widget's ancestors. "Ancestor" can mean either DOM ancestor (ex: TextBox → Form), or a logical parent-child relationship (ex: TooltipDialog → DropDownButton).

For example, if activationTracker is on a TextBox inside a TabContainer inside a TooltipDialog triggered by a DropDownButton, the stack would be TextBox → ContentPane → TabContainer → TooltipDialog → DropDownButton.

on() interface

Call activationTracker.on("active-widget-stack", callback) to track the stack of currently focused widgets.

Call activationTracker.on("deactivated", func) or activationTracker.on("activated", ...) to monitor when when widgets become active/inactive.

delite-activated and delite-deactivated events

Also, if delite/activationTracker is loaded, every widget will emit a non-bubbling delite-activated event when it becomes activate (i.e. when it or logical descendant widget is focused or clicked), and a non-bubbling delite-deactivated event when the opposite happens.