The Object Repository

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Delphi has menu commands you can use to create a new form, a new application, a new data module, a new component, and so on. These commands are located in the File ^ New menu and in other pull-down menus. What happens if you simply select File ^ New ^ Other? Delphi opens the Object Repository, which is used to create new elements of any kind: forms, applications, data modules, thread objects, libraries, components, automation objects, and more.

The New dialog box (shown in Figure 1.11) has several pages, hosting all the new elements you can create, existing forms and projects stored in the Repository, Delphi wizards, and the forms of the current project (for visual form inheritance). The pages and the entries in this tabbed dialog box depend on the specific version of Delphi, so I won't list them here.

FIGURE 1.11:

The first page of the New dialog box, generally known as the "Object Repository"

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The Object Repository has a shortcut menu that allows you to sort its items in different ways (by name, by author, by date, or by description) and to show different views (large icons, small icons, lists, and details). The Details view gives you the description, the author, and the date of the tool, information that is particularly important when looking at wizards, projects, or forms that you've added to the Repository.

The simplest way to customize the Object Repository is to add new projects, forms, and data modules as templates. You can also add new pages and arrange the items on some of them (not including the New and "current project" pages). Adding a new template to Delphi's Object Repository is as simple as using an existing template to build an application. When you have a working application you want to use as a starting point for further development of similar programs, you can save the current status to a template, ready to use later on. Simply use the Project ^ Add To Repository command, and fill in its dialog box.

Just as you can add new project templates to the Object Repository, you can also add new form templates. Simply move to the form that you want to add and select the Add To Repository command of its shortcut menu. Then indicate the title, description, author, page, and icon in its dialog box.

You might want to keep in mind that as you copy a project or form template to the repository and then copy it back to another directory, you are simply doing a copy and paste operation. This isn't much different than copying the files manually.

The Empty Project Template

When you start a new project, it automatically opens a blank form, too. If you want to base a new project on one of the form objects or Wizards, this is not what you want, however. To solve this problem, you can add an Empty Project template to the Gallery.

The steps required to accomplish this are simple:

  1. Create a new project as usual.
  2. Remove its only form from the project.
  3. Add this project to the templates, naming it Empty Project.

When you select this project from the Object Repository, you gain two advantages: You have your project without a form, and you can pick a directory where the project template's files will be copied. There is also a disadvantage—you have to remember to use the File ^ Save Project As command to give a new name to the project, because saving the project any other way automatically uses the default name in the template.

To further customize the Repository, you can use the Tools ^ Repository command. This opens the Object Repository dialog box, which you can use to move items to different pages, to add new elements, or to delete existing ones. You can even add new pages, rename or delete them, and change their order. An important element of the Object Repository setup is the use of defaults:

  • Use the New Form check box below the list of objects to designate a form as the one to be used when a new form is created (File ^ New Form).
  • The Main Form check box indicates which type of form to use when creating the main form of a new application (File ^ New Application) when no special New Project is selected.
  • The New Project check box, available when you select a project, marks the default project that Delphi will use when you issue the File ^ New Application command.

Only one form and only one project in the Object Repository can have each of these three settings marked with a special symbol placed over its icon. If no project is selected as New Project, Delphi creates a default project based on the form marked as Main Form. If no form is marked as the main form, Delphi creates a default project with an empty form.

When you work on the Object Repository, you work with forms and modules saved in the OBJREPOS subdirectory of the Delphi main directory. At the same time, if you use a form or any other object directly without copying it, then you end up having some files of your project in this directory. It is important to realize how the Repository works, because if you want to modify a project or an object saved in the Repository, the best approach is to operate on the original files, without copying data back and forth to the Repository.

Installing New DLL Wizards

Technically, new wizards come in two different forms: They may be part of components or packages, or they may be distributed as stand-alone DLLs. In the first case, they would be installed the same way you install a component or a package. When you've received a stand-alone DLL, you should add the name of the DLL in the Windows Registry under the key \Software\Borland\ Delphi\6.0\Experts. Simply add a new string key under this key, choose a name you like (it doesn't really matter what it is), and use as text the path and filename of the wizard DLL. You can look at the entries already present under the Experts key to see how the path should be entered.

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Project Management Made Easy

Project Management Made Easy

What you need to know about… Project Management Made Easy! Project management consists of more than just a large building project and can encompass small projects as well. No matter what the size of your project, you need to have some sort of project management. How you manage your project has everything to do with its outcome.

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