Mastering Delphi Programming: A Complete Reference Guide

Macros

For the last part of the puzzle, I have to show you how macro recording is implemented. This is actually the most complicated part of the program.

Let's start with the command object. A macro is just a special kind of command, TMacroCommand. As we can see in the following code, it implements an Add command, which stores other commands in the internal list:

type  TMacroCommand = class(TUndoableCommand)  strict private    FCommands: TObjectList<TCommand>;  public    procedure Add(command: TCommand);    procedure AfterConstruction; override;    procedure BeforeDestruction; override;    function Clone: TCommand; override;    procedure Execute; override;  end;procedure TMacroCommand.Add(command: TCommand);begin  FCommands.Add(command);end;