Used for widgets that need text input, such as TextInput
Used for widgets that need pointer input, such as Button
Similar to keyboard focus, but used for checking whether a widget has been tabbed into (focused by pressing the tab key).
If a widget gains a tab focus, then it also gain a keyboard focus. If a widgets gains a keyboard focus, then it also gains a tab focus. However, losing the tab focus doesn't automatically lose the keyboard focus, and losing the keyboard focus doesn't automatically lose the tab focus.
This focus should only be used internally. Do not manually request tab focus unless you know what you are doing.
The focus type of a TricklingEvent. Used to categorise events when focusing widgets in roots.