Creates a GtkFileChooserButton widget which uses dialog as its
file-picking window.
Note that dialog must be a GtkDialog (or subclass) which
implements the GtkFileChooser interface and must not have
GTK_DIALOG_DESTROY_WITH_PARENT set.
Also note that the dialog needs to have its confirmative button
added with response GTK_RESPONSE_ACCEPT or GTK_RESPONSE_OK in
order for the button to take over the file selected in the dialog.
Since 2.6
Creates a GtkFileChooserButton widget which uses dialog as its file-picking window. Note that dialog must be a GtkDialog (or subclass) which implements the GtkFileChooser interface and must not have GTK_DIALOG_DESTROY_WITH_PARENT set. Also note that the dialog needs to have its confirmative button added with response GTK_RESPONSE_ACCEPT or GTK_RESPONSE_OK in order for the button to take over the file selected in the dialog. Since 2.6