Use this kind of Shell Extensions to create your own virtual folders and items to Windows Shell namespace. Using these extensions your users will be able to reach the data through native Windows Explorer interface. This example will show how to use a couple of forms and a few components to implement your own namespace extension.

The Namespace Extension is an ActiveX library like all other Shell Extensions. The first step to do is to create a new ActiveX Library. Create it with the following sequence of operations: open the Repository dialog using File | New | Other... menu, then select the ActiveX tab and click the ActiveX Library icon.

Save the created project.

The next step is to add the instance of TSxDataModule to the project. Every Shell+ component should be placed on SxDataModule 1. This special descendant of TDataModule supplies several internal methods that allow Shell+ components to safely operates in multiple Shell threads and automates their registration and initialization. Note that you can place several Shell+ components onto the same SxDataModule as well as you can add multiple TSxDataModule instances to your project. It is easy to add new SxDataModule to the project - just click corresponding icon in the Repository:

You can save the project now.

Every Namespace Extension library has to operate inside the Windows Shell browser - Explorer.exe. Let's consider the figure below to learn more about different parts of the Explorer. As you can see there are two Shell+ components that help you to implement your own namespace. The first one - TSxVirtualFolder - controls folders and files. The second one interacts with Explorer's menu, status bar and toolbar.

Add the TSxVirtualFolder now. Use this component to create namespace items that are not related with file system structure. The registration data of extension based on this component will be stored in registry. Note that it is one of several possible registration methods. This method has a limited number of junction points if compared with file-related method of registration. On the other side only this method allows to add extensions to system virtual folders such as "My Computer", "Control panel", "My network places" etc.

Configure the Shell View component now. This component shows the list of files and folders at the right pane of Explorer. The TSxSysShellView is used below in this example. This component uses the native Windows 2000 and Windows XP abilities of the Shell View.
Note that this component must be placed on the same form as the Shell Folder component. Use the ShellView property of the TSxVirtualFolder component to link them.

TSxSysShellView has no special properties to be configured.

Add one TPermanentModule to the project. The difference between this TPermanentModule and TSxDataModule is that the TSxDataModule is created dynamically and can be unloaded at any time while TPermanentModule exists always in one instance. It is this module should carry all data-related components such as TDataSet successors, TSxDataProvider successors and their related components.


Place a TSxSimpleTreeProvider component onto this Data Module. Connect it to the DataProvider property of the TSxVirtualFolder. Do not forget to modify the uses clause to avoid compiler errors.

Right click the component now. You will see the menu with a "Tree editor..." item at the top. Select this item. The editor of the TSxSimpleTreeProvider will appear.

Only for V.I.P