Contents

Preface

The samples

What to expect with version B

The code and documentation

How the chapters are organized

Reading notation diagrams

Class architecture diagrams

Interaction diagrams

Taligent Chat

High-level architecture

Model subsystem

Design notes

Changing persistent data

Streaming relevant data

Model changes

Supporting mutable data

Protocol subsystem

Design notes

Separating the handler from its clients

The model owns TChatHandler

Processing a message

Simplified interface

Announcing a new member

Semaphores and locks

Interface subsystem

Design notes

MChatView and MChatHandler

Actions handled by the view

Buttons are tied to actions

Resizing windows

Interesting mechanisms

Bringing up a dialog

Joining a caucus

Receiving a caucus message

Extensions

Extending the Chat protocol

Providing multiple views

Changing the user interface

Making the Taligent Chat discussion persist

Implementing Undo

Removing delay on sending

Removing delay on receiving

Concurrent Actors

High-level architecture

Universe subsystem

Design notes

Destroying objects through a thread

No thread priorities

Minimal protocol for TAbstractActor

Game subsystem

Design notes

Multiple asteroid classes

Adding levels of difficulty

Interface subsystem

Design notes

Choosing a program framework

Choosing presentation classes

Choosing an off-screen buffer

Movement subsystem

Design notes

Using a single mover thread

Avoiding deadlocks in the mover thread

Keeping time

The mover thread doesn't own movable objects

Refresh subsystem

Design notes

Avoiding refresh overkill

Two-phase refresh

Avoiding deadlocks in the refresh thread

No back-to-front ordering necessary

The refresh thread doesn't own refreshing objects

Collision subsystem

Design notes

Avoiding a separate thread for collision

Using notification

Dynamic typing

Local utility classes

Design notes

Separating the thread from its state

Creating a type-safe queue

Interesting mechanisms

Destroying actors cleanly

Queuing an actor for deletion

Deleting queued actors

Pausing the mover and refresh threads

Locking the thread, not the data

Refreshing the screen

Sending refresh notification

Updating the view from the buffer

Extensions

Interesting play

Efficient screen updating

Refresh times

Movement times

Collision behaviors

Stock Browser

High-level architecture

Stock Server subsystem

Design notes

To stream or not to stream

It's better to be abstract

RPC services versus Message Streams

Stock Picker subsystem

Design notes

Access to stock data

Support for drag and drop

Look-up by name

Stock Viewer subsystem

Design notes

Supporting multiple views

Support for drag and drop functionality

Graphics subsystem

Design notes

An extensible design

MGraphic versus TView

Common Classes

Interesting mechanisms

Graphing a Stock

Choosing an item from the View menu

Reconstructing a graph

Extensions

Providing additional stock information

Graphing more than one stock

Adding and modifying graphs

Providing a "live" server

Simplified stock data

WebRunner Sample

High-level architecture

Web Document subsystem

Design notes

Editable text with embedded components

HandleModelChanged

TWebModel persistence

Data Access subsystem

Design notes

Accommodating CERN

Encapsulated C library

TScrapItem

Translation subsystem

Design Notes

Global translators

Web Link subsystem

Design notes

Context-sensitive components

TWebLink isn't a model

Command subsystem

Design notes

Capturing Mosaic functionality

Operating on an entire model selection

Graphic Document subsystem

Design notes

Component reusability

Non-model drag and drop

Interesting mechanisms

Activating a hypertext link

Acquiring the viewer's reference

In-place opening

Out-of-place opening

Extensions

Supporting varying media types

Reusing link and image document components

Implementing additional HTML protocol

Other common browser features

Taligent Selection Tool

High-level architecture

Mapping subsystem

Design notes

Coordinating geometries

Single view for MSelectionMapping

Feedback subsystem

Design notes

Feedback view

Target subsystem

Design Notes

Downsizing

Coordinating coordinates

Tool subsystem

Design notes

Interactors

Convenience subsystem

Interesting mechanisms

Providing drop acceptance feedback

Supporting a selection

Dragging a selection

Extensions

Make selecting undoable

Make dropping undoable

Make TDOMDocument-ComponentView a behavior

Mechanism Grab Bag