A dialog is very similar to a page and can contain a variety of items such as text, images or radio buttons. While pages are shown in the main window of your application, dialogs are separate windows that can be opened on top of your application window.
Dialogs can be shown using the DialogEx.Show action, and closed using the DialogEx.Close action.
Note: You cannot navigate pages when a dialog is visible, nor can you show another instance of a dialog if it is already visible. You can however show a dialog from a dialog.
Note: Dialogs and pages are the "surfaces" that objects can be placed on.
When you click on the dialog surface, the dialog settings are displayed in the properties pane. Double-clicking on the dialog surface opens the Properties dialog for the dialog.
Tip: You can switch between dialogs and pages by clicking on their tabs at the top of the work area, or by double-clicking on any page or dialog in the project explorer. By default, dialog tabs are shown to the right of page tabs, however this can be changed on the Tabs preference (Edit > Preferences, Environment > Tabs).
Tip: You can change the order of the dialogs in your project through the Organize Dialogs dialog (Dialog > Arrange).