# What really makes a Dialog window behave as a modal dialog?

CreateDialog[DefaultButton[], Modal -> True]


creates a modal Dialog, one which needs to be closed before the front-end becomes available for further interaction.

Very useful. However

CreateDialog[DefaultButton[], Modal -> True, WindowFrame -> "ThinFrame"]


creates a Dialog which is not modal despite the Modal option being given.

Why does this happen? What really determines that a dialog is modal?

keywords: FrontEnd, block, Dialog, Window, WindowFrame

Reported to WRI. Will keep you informed.

[CASE:2559336] Feedback/ Dialogs documentation status:

[...] I have forwarded a report of this to the appropriate people in our development team with the information you provided and included your contact information. [...] I have included a comment about modifying the documentation to give more explanation, as well. [...]

What really makes Dialog a model dialog is:

WindowFrame -> "ModalDialog"

(*or*)

WindowFrame -> "MovableModalDialog"


So be careful when changing WindowFrame with the expectation that your dialog will remain modal.

Funny proof is that the following:

CreateDialog[DefaultButton[], WindowFrame -> "ModalDialog", Modal -> False]


is a modal dialog.

I think this is useful info. The Mathematica tutorials and guides concerning Dialog do not say anything about this matter.

• I indeed urge you to report this as a defect in the documentation. – m_goldberg Feb 26 '15 at 16:36
• @m_goldberg done – Kuba Feb 26 '15 at 18:05
• +1 Looks like either a bug or a design oversight – Mike Honeychurch Feb 26 '15 at 22:16