added bind to visible event function to callback when visibility changes within tabs

diff --git a/gr-wxgui/src/python/common.py b/gr-wxgui/src/python/common.py
index 9c97ce1ecad898a32e1871f9445c42713db7fd9e..f355fd3ce6d91e4deecf19529702d672674f327c 100644 (file)
--- a/gr-wxgui/src/python/common.py
+++ b/gr-wxgui/src/python/common.py
@@ -19,6 +19,41 @@
 # Boston, MA 02110-1301, USA.
 #
 
+import wx
+
+def bind_to_visible_event(win, callback):
+       """
+       Bind a callback to a window when its visibility changes.
+       Specifically, callback when the window changes visibility
+       when a notebook tab event in one of the parents occurs.
+       @param win the wx window
+       @param callback a 1 param function
+       """
+       #is the window visible in the hierarchy
+       def is_wx_window_visible(my_win):
+               while True:
+                       parent = my_win.GetParent()
+                       if not parent: return True #reached the top of the hierarchy
+                       #if we are hidden, then finish, otherwise keep traversing up
+                       if isinstance(parent, wx.Notebook) and parent.GetCurrentPage() != my_win: return False
+                       my_win = parent
+       #call the callback, the arg is shown or not
+       def callback_factory(my_win, my_callback):
+               cache = [None]
+               def the_callback(*args):
+                       visible = is_wx_window_visible(my_win)
+                       if cache[0] != visible: my_callback(visible)
+                       cache[0] = visible
+               return the_callback
+       handler = callback_factory(win, callback)
+       #bind the handler to all the parent notebooks
+       while win:
+               if isinstance(win, wx.Notebook):
+                       win.Bind(wx.EVT_NOTEBOOK_PAGE_CHANGED, handler)
+               if not win.GetParent():
+                       win.Bind(wx.EVT_ACTIVATE, handler)
+               win = win.GetParent()
+
 #A macro to apply an index to a key
 index_key = lambda key, i: "%s_%d"%(key, i+1)