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These TAGS provide INFORMATION to FLEX compiler regarding the usage of our COMPONENT. Examples are Bindable, EVENT, DefaultProperty, Inspectable etc.

These tags provide information to Flex compiler regarding the usage of our component. Examples are Bindable, Event, DefaultProperty, Inspectable etc.

We USE this function to limit the data view in the collection to a SUBSET of SOURCE data object. The function must TAKE a single Object parameter, which corresponds to a collection item, and must return a BOOLEAN value specifying whether to include the item in the view.

We use this function to limit the data view in the collection to a subset of source data object. The function must take a single Object parameter, which corresponds to a collection item, and must return a Boolean value specifying whether to include the item in the view.

A CURSOR is a position INDICATOR; it POINTS to a particular item in the collection. We use view cursor to traverse items in a collection’s data view and modify the data in collection.

A view cursor INCLUDES following methods:

1. The moveNext() and movePrevious() to move the cursor forward or backward. Use beforeFirst or afterLast properties to check WHETHER we have reached the bounds.
2. The findAny(), findFirst() and findLast() methods move the cursor to an item that matches the parameter.

A cursor is a position indicator; it points to a particular item in the collection. We use view cursor to traverse items in a collection’s data view and modify the data in collection.

A view cursor includes following methods:

 Collections dispatch CollectionEvent, PropertyChangeEvent and FlexEvent OBJECTS.

• Collections dispatch a CollectionEvent when there is a change in collection. The property kind for a CollectionEvent OBJECT can be used to find which kind of change occurred. This property is compared against CollectionEventKind constants to find what the change was for example, UPDATE etc.
• The CollectionEvent object includes an items property that is an ARRAY of objects. For ADD and REMOVE kind events this contains added or removed items, but for UPDATE it contains an array of PropertyChangeEvent objects.
• PropertyChangeEvent class has kind property to indicate the WAY in which property changed. This can be determined by comparing kind property with PropertyChangeEventKind constants, for example UPDATE. This EVENT object also has properties to indicate the values before and after the change.
• View cursor objects dispatch a FlexEvent with type property mx.events.FlexEvent.CURSOR_UPDATE when the cursor position changes.

 Collections dispatch CollectionEvent, PropertyChangeEvent and FlexEvent objects.

This METHOD prevents the events that represent changes to the underlying DATA from being broadcasted by the view. It also prevents collection from being updated. This method is useful where multiple items in collection are being edited at once. By disabling the auto update the changes are RECEIVED as a batch instead of multiple events. Also in a DataGrid this method prevents update to the collection while a specific item is SELECTED. When item is no longer selected the DataGrid controls calls enableAutoUpdate() method.

This method prevents the events that represent changes to the underlying data from being broadcasted by the view. It also prevents collection from being updated. This method is useful where multiple items in collection are being edited at once. By disabling the auto update the changes are received as a batch instead of multiple events. Also in a DataGrid this method prevents update to the collection while a specific item is selected. When item is no longer selected the DataGrid controls calls enableAutoUpdate() method.