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Interface quicktime.app.spaces.DynamicCollection

public interface DynamicCollection
extends Collection
The DynamicCollection uses the Protocol class to enable the application to dynamically type members on a collection by collection basis. Dynamic collections use the protocol to test to see if an object is appropriate before it is accepted as a candidate for membership of the collection.

This enables an application to tighten the restrictions on membership on a case by case basis. For example, the DirectGroup is a DynamicCollection, of which the fundamental requirement is that the member implement the QTDrawable interface. However if a particular application wanted to ensure that for a particular group only movies were in the collection, the application could get the Protocol object for that particular DirectGroup and add the MoviePlayer class to the collection of class objects that make up the Protocol. Consequent uses of that direct group would ensure that the object being added was both a QTDrawable and MoviePlayer before the object was added. The application (having specified this protocol) can then make certain assumptions about the type of object that is a member of the collection.

Changing a protocol after a member has been added to the collection will not mean that existing members are removed if they do not match the new protocol, thus protocols should only be specified when the collection is empty.

See Also:
Protocol

Method Index

o getProtocol()
Returns the Protocol class that is used to when testing an object's appropriateness for membership of a collection.

Methods

o getProtocol 
 public abstract Protocol getProtocol()
Returns the Protocol class that is used to when testing an object's appropriateness for membership of a collection.

Returns:
a Protocol object. 
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