add a 'window' mode to the popup view

this mode allows popup windows which do not stay on top of all the
windows on the desktop, they only stay on top of their parent.

enaml/qt/q_popup_view.py

@@ -826,7 +826,7 @@ def mousePressEvent(self, event):
                     if not path.isEmpty() and not path.contains(pos):
                         event.accept()
                         self.close()
-            elif win_type == Qt.ToolTip:
+            elif win_type == Qt.ToolTip or win_type == Qt.Window:
                 if path.isEmpty() or path.contains(pos):
                     event.accept()
                     self.close()

enaml/qt/qt_popup_view.py

@@ -26,6 +26,7 @@
 WINDOW_TYPES = {
     'popup': Qt.Popup,
     'tool_tip': Qt.ToolTip,
+    'window': Qt.Window,
 }
 
 

enaml/widgets/popup_view.py

@@ -97,13 +97,24 @@ class PopupView(Widget):
     #: reference to a transient popup.
     popup_views = []
 
-    #: The type of the window to create. A 'popup' window will close
-    #: when the user presses escape or clicks outside of the window.
-    #: A 'tool_tip' window will close when the user clicks the window.
-    #: The popup window is useful for showing configuration dialogs,
-    #: while the tool tip window is useful for notification messages.
-    #: The window type cannot be changed once the widget is created.
-    window_type = d_(Enum('popup', 'tool_tip'))
+    #: The type of the window to create. Each has different behavior. The
+    #: window type cannot be changed after the widget is created.
+    #:
+    #: 'popup'
+    #:     This window will close when the user presses escape or clicks
+    #:     outside of the window. It will block all external interactions
+    #:     until it is closed.
+    #:
+    #: 'tool_tip'
+    #:     This window will close when the user clicks inside the window.
+    #:     It stays on top of all the other windows on the desktop. It is
+    #:     useful for showing mouse cursor or desktop notifications.
+    #:
+    #: 'window'
+    #:     This window will close when the user clicks inside the window.
+    #:     It stays on top of its parent, but not the other windows on
+    #:     the desktop. It is useful for notifications inside a window.
+    window_type = d_(Enum('popup', 'tool_tip', 'window'))
 
     #: The mode to use for anchoring. The 'parent' mode uses a point
     #: on the parent or the desktop as the target anchor, the 'cursor'
@@ -153,7 +164,7 @@ class PopupView(Widget):
 
     #: Whether or not close the popup view on a mouse click. For 'popup'
     #: windows, this means clicking outside of the view. For 'tool_tip'
-    #: windows, this means clicking inside of the view.
+    #: and 'window' windows, this means clicking inside of the view.
     close_on_click = d_(Bool(True))
 
     #: Whether or not the background of the popup view is translucent.

examples/widgets/popup_view.enaml

@@ -116,7 +116,7 @@ enamldef Main(Window): win:
             clicked :: ConfigPopup(self).show()
         PushButton:
             text = 'Show Window Notification'
-            clicked :: NotificationPopup(win).show()
+            clicked :: NotificationPopup(win, window_type='window').show()
         PushButton:
             text = 'Show Desktop Notification'
             clicked :: NotificationPopup().show()