""" Hello, and welcome to this test of the wxTreeItemData class. The wxTreeItemData class can be used to associate a python object with a wxTreeCtrl item. In this sample, its use is demonstrated via a tree control that shows the contents of a python namespace according to the standard dir() command. Every item in the tree has its label taken from the dir() output, and 'behind it' a reference to the python object is stored in a wxTreeItemData object. As you may have guessed by now, this sample automatically displays '__doc__' strings if the selected python object happens to have one. Please expand the pyTree object to learn more about the implementation. Version 1.0, April 4 1999. Harm van der Heijden (H.v.d.Heijden@phys.tue.nl) P.S. Check out the string module. It's imported in this sample not because it's used, but because it's so beautifully documented... """ from wxPython import wx import string # Don't use it, but it's fun expanding :-) #---------------------------------------------------------------------- def _getindent(line): """Returns the indentation level of the given line.""" indent = 0 for c in line: if c == ' ': indent = indent + 1 elif c == '\t': indent = indent + 8 else: break return indent def _sourcefinder(func): """Given a func_code object, this function tries to find and return the python source code of the function.""" try: f = open(func.co_filename,"r") except: return "(could not open file %s)" % (func.co_filename,) for i in range(func.co_firstlineno): line = f.readline() ind = _getindent(line) msg = "" while line: msg = msg + line line = f.readline() # the following should be <= ind, but then we get # confused by multiline docstrings. Using == works most of # the time... but not always! if _getindent(line) == ind: break return msg #---------------------------------------------------------------------- class pyTree(wx.wxTreeCtrl): """ This wxTreeCtrl derivative displays a tree view of a Python namespace. Anything from which the dir() command returns a non-empty list is a branch in this tree. """ def __init__(self, parent, id, root): """ Initialize function; because we insert branches into the tree as needed, we use the ITEM_EXPANDING event handler. The ITEM_COLLAPSED handler removes the stuff afterwards. The SEL_CHANGED handler attempts to display interesting information about the selected object. """ wx.wxTreeCtrl.__init__(self, parent, id) self.root = self.AddRoot(str(root), -1, -1, wx.wxTreeItemData(root)) if dir(root): self.SetItemHasChildren(self.root, wx.TRUE) wx.EVT_TREE_ITEM_EXPANDING(self, self.GetId(), self.OnItemExpanding) wx.EVT_TREE_ITEM_COLLAPSED(self, self.GetId(), self.OnItemCollapsed) wx.EVT_TREE_SEL_CHANGED(self, self.GetId(), self.OnSelChanged) self.output = None def SetOutput(self, output): """ Set output function (accepts single string). Used to display string representation of the selected object by OnSelChanged. """ self.output = output def OnItemExpanding(self,event): """ The real workhorse of this class. First we retrieve the object (parent) belonging to the branch that is to be expanded. This is done by calling GetPyData(parent), which is a short-cut for GetPyItemData(parent).Get(). Then we get the dir() list of that object. For each item in this list, a tree item is created with associated wxTreeItemData referencing the child object. We get this object using child = getattr(parent, item). Finally, we check wether the child returns a non-empty dir() list. If so, it is labeled as 'having children', so that it may be expanded. When it actually is expanded, this function will again figure out what the offspring is. """ item = event.GetItem() obj = self.GetPyData( item ) lst = dir(obj) for key in lst: new_obj = getattr(obj,key) new_item = self.AppendItem( item, key, -1, -1, wx.wxTreeItemData(new_obj) ) if dir(new_obj): self.SetItemHasChildren(new_item, wx.TRUE) def OnItemCollapsed(self, event): """ We need to remove all children here, otherwise we'll see all that old rubbish again after the next expansion. """ item = event.GetItem() self.DeleteChildren(item) def OnSelChanged(self, event): """ If an output function is defined, we try to print some informative, interesting and thought-provoking stuff to it. If it has a __doc__ string, we print it. If it's a function or unbound class method, we attempt to find the python source. """ if not self.output: return obj = self.GetPyData( event.GetItem() ) msg = str(obj) if hasattr(obj, '__doc__'): msg = msg+"\n\nDocumentation string:\n\n%s" % ( getattr(obj, '__doc__'),) # Is it a function? func = None if hasattr(obj, "func_code"): # normal function func = getattr(obj, "func_code") elif hasattr(obj, "im_func"): # unbound class method func = getattr(getattr(obj, "im_func"), "func_code") if func: # if we found one, let's try to print the source msg = msg+"\n\nFunction source:\n\n" + _sourcefinder(func) apply(self.output, (msg,)) #---------------------------------------------------------------------- overview = __doc__ def runTest(frame, nb, log): split = wx.wxSplitterWindow(nb, -1) tree = pyTree(split, -1, __main__) text = wx.wxTextCtrl(split, -1, "", wx.wxDefaultPosition, wx.wxDefaultSize, wx.wxTE_MULTILINE) split.SplitVertically(tree, text, 200) tree.SetOutput(text.SetValue) tree.SelectItem(tree.root) text.SetBackgroundColour(wxNamedColour("LIGHT BLUE")) tree.SetBackgroundColour(wxNamedColour("LIGHT BLUE")) return split #---------------------------------------------------------------------- if __name__ == '__main__': class MyFrame(wx.wxFrame): """Very standard Frame class. Nothing special here!""" def __init__(self): """Make a splitter window; left a tree, right a textctrl. Wow.""" import __main__ wx.wxFrame.__init__(self, wx.NULL, -1, "PyTreeItemData Test", wx.wxDefaultPosition, wx.wxSize(800,500)) split = wx.wxSplitterWindow(self, -1) tree = pyTree(split, -1, __main__) text = wx.wxTextCtrl(split, -1, "", wx.wxDefaultPosition, wx.wxDefaultSize, wx.wxTE_MULTILINE) split.SplitVertically(tree, text, 200) tree.SetOutput(text.SetValue) tree.SelectItem(tree.root) class MyApp(wx.wxApp): """This class is even less interesting than MyFrame.""" def OnInit(self): """OnInit. Boring, boring, boring!""" frame = MyFrame() frame.Show(wx.TRUE) self.SetTopWindow(frame) return wx.TRUE app = MyApp(0) app.MainLoop()