Container Control of Activation

The container application determines how to activate its component objects: either it allows the inside-out objects to handle events directly or it intercedes and only activates them upon an explicit action. This is true regardless of the capability or preference setting of the object. That is, even though an object may register inside-out activation, it can be treated by a particular container as outside-in. Use an activation style for your container that is most appropriate for its specific use and is in keeping with its own native style of activation so that objects can be easily assimilated.

Regardless of the activation capability of the object, a container should always activate its content objects of the same type consistently. Otherwise, the unpredictability of the interface is likely to impair its usability. Following are four potential container activation methods and when to use them.

Activation method

When to use

Outside-in throughout

This is the most common design for containers that often embed large OLE objects and deal with them as whole units. Because many available OLE objects are not yet inside-out capable, most compound document editors support outside-in throughout to preserve uniformity.

Inside-out throughout

Ultimately, OLE containers will blend embedded objects with native data so seamlessly that the distinction dissolves. Inside-out throughout containers will become more feasible as increasing numbers of OLE objects support inside-out activation.

Outside-in plus inside-out preferred objects

Some containers may use an outside-in model for large, foreign embeddings but also include some inside-out preferred objects as though they were native objects (by supporting OLEMISC_ACTIVATEWHENVISIBLE). For example, an OLE document might present form control objects as inside-out native data while activating larger spreadsheet and chart objects as outside-in.

Switch between inside-out throughout and outside-in throughout

Visual programming and forms layout design applications may include design and run modes. In this type of environment, a container typically holds an object that is capable of inside-out activation (if not preferable) and alternates between outside-in throughout when designing and inside-out throughout when running.