Application object

The framework approach to code reuse provides a concrete, yet incomplete, implementation of the architecture The rules and policies about how application objects interact are codified and enforced by the framework itself. Frameworks can be both white-box—a template method in the superclass must be overriden by a subclass after understanding the calls made in the superclass implementation—and black-box, in which interfaces for the plug-in calls are explicitly specified and implemented according to the spec. 

Create one application object. This object coordinates and mediates among the UI widgets and between the widgets and the business objects. The application object is created at the appropriate point in the dialog flow in contrast, the business objects are created from persistent storage. 

The application object creates its corresponding UI panel and populates it with its widgets. 

The application object registers the widgets as its observer later, a single changed method will inform all these widgets to update themselves. 

The application object registers itself as the listener for events from each relevant widget if necessary, it creates intermediate adapter objects to listen directly for these... 

The application object registers itself as an observer for the relevant business objects. When they change they update the application object, which updates the widgets if necessary (see Figure 12.6). 

The widget generates the appropriate event to the application object (possibly through an intermediate adapter object). 

The application object makes necessary changes to its state to reflect the progress of the interaction dialog then it generates a command to the business object then it propagates updates to the widgets. 

The widgets update themselves by calling back to the application object for the state information they need (again, possibly translated by the intermediate adapter). 

You can sometimes make the user interface elements and the application object reusable so that you can create larger panels and application objects such as the following ... 

Devise an event protocol to make these elements composable. For example, each application object checks with its container before it sends commands to its business objects. 

If the application object represents an action in progress, name it as such. 

Although ActiveCell and Selection are properties, not objects, you can treat them like objects. (ActiveCell is a property of the Application object, or the ActiveWindow property of the Application object.) The Application object has the following properties that you can treat just as though they were objects the ActiveWindow, ActiveWorkbook, ActiveSheet, ActiveCell, Selection and ThisWorkbook properties. Since there is only one Application object, you can omit the reference to Application and simply use ActiveCell. 

This annexure calls for comprehensive manufacturing procedures used to produce the batches of the product used to establish quality and efficacy, as also to be reflected in Annexure 16. Blank mcmufacturing documents may be submitted, however, in view of the confidentiality of these documents, memy applicants object to submitting these and rather submit the manufacturing process flow diagram and a detailed description thereof. 

Microsoft Office allows the option to record macros for performing repetitive tasks. Although macros are somewhat limited for the development of true VBA applications, macro recording can be used effectively to learn VBA or create templates of code that can be generalized with the addition of variables. If VBA for Microsoft Office is enabled, you only need to press alt-fi i to open the VBA Integrated Development Environment (IDE). A search of the on-line help for Application Object will provide an interactive object hierarchy that describes (with detailed code examples) each object or collection. There are literally thousands of objects within the Microsoft Office application object models. Another very useful tool within the VBA environment is the Object Browser, which can be invoked with the F2 key. The Object Browser can be particularly useful to learn the objects of external components that have been referenced from within VB or VBA. This method is an excellent way to get started with new object types and follow along with the documentation. An example is shown in Figure 18.3 from the Excel 2000 VBA IDE. In this example, the Excel is the automation client and Sciex Analyst method component... 

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