Take a quick look at the contents of the $(DELPHI)\Demos\ShellControls folder, you'll find a Delphi package hosting 4 Delphi components: ShellTreeView, ShellComboBox, ShellListView and ShellChangeNotifier. The first three components enable you to write your own Windows Explorer. The fourth component, ShellChangeNotifier, seems to be the one we are looking for.

Note: after you install the package containing those components (vclshlctrls.dpk), the component will be placed on the Samples tab of the component palette.

The TShellChangeNotifier component acts as a wrapper around the SHChangeNotify API function. Unfortunately, when you look for TShellChangeNotifier properties and more importantly the events, you'll find the component is equipped with just one event: OnChange. The OnChange event gets fired whenever some of the selected shell change events specified for the NotifyFilters property occur. Even more, the OnChange event has no shell-change specific parameters like what is the exact name (and location) of the file that, for example, was created somewhere on the system. The only thing you will be notified using this component is that *something* has happened *somewhere* in the monitored folder / subfolder.

This, of course, is not enough for what we want - time to write our own wrapper around the SHChangeNotify API function that gives us the full control over the shell changes - or even better, search the Internet for some ready made component.

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