The Modal Popup feature of RadWindow creates a semi-transparend background behind the popup that hides the rest of the page so that the user cannot interact with the page until the modal dialog is closed.
The main features our ASP.NET modal window has are:
- the modal background resizes with the browser
- the modal dialog is centered by default
- the CenterIfModal property can make it respect the Top and Left properties with regard to an OffsetElement, if one is set
- the modality can also be toggled through the client-side API of the control during runtime, not only with the server Modal property
- focusable controls on the main page cannot be tabbed into when a modal dialog is opened - their tabIndex is set to -1 and restored when the dialog is closed
- the predefined dialogs (RadAlert, RadConfirm and RadPrompt) are always modal to mimic the behaviour of the original browser dialog boxes