In IUP you can create your own dialogs or use one of the predefined dialogs. To create your own dialogs you will have to create all the controls of the dialog before the creation of the dialog. All the controls must be composed in a hierarchical structure so the root will be used as a parameter to the dialog creation.

When a control is created, its parent is not known. After the dialog is created all elements receive a parent. This mechanism is quite different from that of native systems, who first create the dialog and then the element are inserted, using the dialog as a parent. This feature creates some limitations for IUP, usually related to the insertion and removal of controls.

Since the controls are created in a different order from the native system, native controls can only be created after the dialog. This will happen automatically when the application call the IupShow function to show the dialog. But we often need the native controls to be created so we can use some other functionality of those before they are visible to the user. For that purpose, the IupMap function was created. It forces IUP to map the controls to their native system controls. The IupShow function internally uses IupMap before showing the dialog on the screen. IupShow can be called many times, but the map process will occur only once.

IupShow can be replaced by IupPopup. In this case the result will be a modal dialog and all the other previously shown dialogs will be unavailable to the user. Also the program will interrupt in the function call until the application return IUP_CLOSE or IupExitLoop is called.

All dialogs are automatically destroyed in IupClose.