FilteredList/SortedList

[Knut Arne Vedaa]

> These lists have always been driven by the requirements of TableView,
> but I'm having a hard time understanding how the newly proposed API will
> fit in (and what will be required of me and / or end users of the
> TableView control). It would be great if you could show some examples of
> how a developer would instantiate a TableView that is:

Generally, this shouldn't mean any changes to TableView at all. The 
consumers of FilteredList/SortableList should not see them as such, but 
simply as implementations of ObservableList.

The task of TableView is to observe an ObservableList and update itself 
according to changes of the list. These changes may be the result of 
adding, removing, sorting, filtering and on. How the list changes 
themselves is not something TableView (or other controls that listens to 
ObservableLists) should care about.

> 1) always in a sorted state

First, it may not always be desireble to have a TableView that is always 
in a sorted state, so a way to configure this (autoSortProperty) would 
be needed.

> 2) able to filtered based on a user typing

This would be the task of the API user to hook up a FilteredList with a 
suitable filter (with mutable predicate based on values of other 
controls) to the TableView.

> 3) is always sorted and able to be filtered based on user input

For sorting, I think TableView should implement it with an internal 
SortedList. That is, the user hooks up an ObservableList to the 
TableView, but internally TableView wraps with in a SortedList and uses 
the latter as the source for the display. This way you can, as you say, 
also revert to the unsorted if so desired. An open question here is 
whether this sortedList should be exposed, which may be desirable if the 
user *actually* wanted to use the sorted list for something (which is 
the current behaviour with sort in place...)

So in this sense, SortedList might be driven by the needs of TableView, 
while FilteredList would be completely unrelated. FilteredList might 
have som uses with ComboBox, though. (E.g. "find" or narrow the 
possibilities as the user types.)


Knut Arne Vedaa