[This topic is pre-release documentation and is subject to change in future releases. Blank topics are included as placeholders.]

This view is a very simple view presenting the last event posted by the parent view to any subviews. Only the very last event object is kept by this view. The update method invoked by the parent view supplies new data in an object array, of which the view keeps the very last instance as the 'last' or newest event. The view always has the same schema as the parent view and attaches to anything, and accepts no parameters. Useful is the last view for example for "stocks.time_window(100).last()". Notice that "stocks.last().Count" and "stocks.win:length(10).std:lastevent().std:size()" must always return 0 or 1. Thus if 5 pieces of new data arrive, the child view receives 5 elements of new data and also 4 pieces of old data which is the first 4 elements of new data. I.e. New data elements immediatly gets to be old data elements. Old data received from parent is not handled, it is ignored. We thus post old data as follows: last event is not null + new data from index zero to N-1, where N is the index of the last element in new data

The following tables list the members exposed by the LastElementView type.

Public Methods

  NameDescription
AddView
Add a view to the viewable object.
(Inherited from ViewSupport.)
AttachesTo
Return null if the view will accept being attached to a particular object.
(Overrides .AttachesTo(Viewable).)
Equals (Inherited from Object.)
GetEnumerator
Returns an enumerator that iterates through the collection.
(Overrides .GetEnumerator().)
GetHashCode (Inherited from Object.)
GetType (Inherited from Object.)
GetViews
Returns all added views.
(Inherited from ViewSupport.)
RemoveView
Remove a view.
(Inherited from ViewSupport.)
ToString
Returns a String that represents the current Object.
(Overrides .ToString().)
Update
Notify that data has been added or removed from the Viewable parent. The last object in the newData array of objects would be the newest object added to the parent view. The first object of the oldData array of objects would be the oldest object removed from the parent view.

If the call to update contains new (inserted) data, then the first argument will be a non-empty list and the second will be empty. Similarly, if the call is a notification of deleted data, then the first argument will be empty and the second will be non-empty. Either the newData or oldData will be non-null. This method won't be called with both arguments being null, but either one could be null. The same is true for zero-length arrays. Either newData or oldData will be non-empty. If both are non-empty, then the update is a modification notification.

When update() is called on a view by the parent object, the data in newData will be in the collection of the parent, and its data structures will be arranged to reflect that. The data in oldData will not be in the parent's data structures, and any access to the parent will indicate that that data is no longer there.

(Overrides .Update(EventBean[](), EventBean[]()).)

Protected Methods

  NameDescription
Finalize (Inherited from Object.)
MemberwiseClone (Inherited from Object.)

Protected Fields

  NameDescription
parent
Parent viewable to this view - directly accessible by subclasses.
(Inherited from ViewSupport.)

Public Constructors

  NameDescription
LastElementViewNew
Constructor.

Public Properties

  NameDescription
EventType
Provides metadata information about the type of object the event collection contains.
(Overrides .EventType.)
HasViews
Test is there are any views to the Viewable.
(Inherited from ViewSupport.)
Id
Gets the unique id for the view
(Inherited from ViewSupport.)
Parent
Gets or sets the View's parent Viewable.
(Inherited from ViewSupport.)

Explicit Interface Implementations

  NameDescription
Explicit interface implemetationIEnumerable.System.Collections.IEnumerable.GetEnumerator
Returns an enumerator that iterates through a collection.
(Inherited from ViewSupport.)