diff -r 5e05d7d3db9c Lib/idlelib/ClassBrowser.py
--- a/Lib/idlelib/ClassBrowser.py	Sat Mar 01 07:53:28 2014 -0500
+++ b/Lib/idlelib/ClassBrowser.py	Sun Mar 02 20:12:09 2014 +0530
@@ -5,7 +5,6 @@
 - reparse when source changed (maybe just a button would be OK?)
     (or recheck on window popup)
 - add popup menu with more options (e.g. doc strings, base classes, imports)
-- show function argument list? (have to do pattern matching on source)
 - should the classes and methods lists also be in the module's menu bar?
 - add base classes to class browser tree
 """
@@ -13,6 +12,8 @@
 import os
 import sys
 import pyclbr
+import inspect
+import imp
 
 from idlelib import PyShell
 from idlelib.WindowList import ListedToplevel
@@ -134,7 +135,10 @@
 
     def GetText(self):
         if self.isfunction:
-            return "def " + self.name + "(...)"
+            module = imp.load_source('module',self.file)
+            function = getattr(module,self.name)
+            args = inspect.getargspec(function)
+            return "def " + self.name + "({})".format(self.FormatArgumentList(args))
         else:
             return "class " + self.name
 
@@ -180,6 +184,20 @@
             list.append(name)
         return list
 
+    def FormatArgumentList(self,args):
+        #See documentation of inspect.argspec(),for 
+        #more information on how args is formatted.
+        formatted_args = []
+        if args.args :
+            formatted_args = formatted_args + [', '.join(args.args)]
+        if args.varargs:
+           formatted_args = formatted_args + ['*' + args.varargs]
+        if args.keywords:
+           formatted_args = formatted_args + ['**' + args.keywords]
+        if args.defaults:
+           formatted_args = formatted_args + ['defualts=' + str(args.defaults)]
+        return ', '.join(formatted_args)
+
 class MethodBrowserTreeItem(TreeItem):
 
     def __init__(self, name, cl, file):
@@ -188,7 +206,12 @@
         self.file = file
 
     def GetText(self):
-        return "def " + self.name + "(...)"
+        module = imp.load_source('m',self.file)
+        class_ = getattr(module, self.cl.name)
+        function = getattr(class_, self.name)
+        args = inspect.getargspec(function)
+        formatted_args = self.FormatArgumentList(args)
+        return "def " + self.name + "({})".format(formatted_args)
 
     def GetIconName(self):
         return "python" # XXX
@@ -202,7 +225,24 @@
         edit = PyShell.flist.open(self.file)
         edit.gotoline(self.cl.methods[self.name])
 
+    def FormatArgumentList(self,args):
+        #See documentation of inspect.argspec(),for 
+        #more information on how args is formatted.
+        formatted_args = []
+        if args.args :
+            formatted_args = formatted_args + [', '.join(args.args)]
+        if args.varargs:
+           formatted_args = formatted_args + ['*' + args.varargs]
+        if args.keywords:
+           formatted_args = formatted_args + ['**' + args.keywords]
+        if args.defaults:
+           formatted_args = formatted_args + ['defualts=' + str(args.defaults)]
+        return ', '.join(formatted_args)
+
 def main():
+    from idlelib.PyShell import PyShell, PyShellFileList
+    from tkinter import Tk, Button
+
     try:
         file = __file__
     except NameError:
@@ -213,9 +253,18 @@
             file = sys.argv[0]
     dir, file = os.path.split(file)
     name = os.path.splitext(file)[0]
-    ClassBrowser(PyShell.flist, name, [dir])
+    root = Tk()
+    root.title('Class Browser Test Dialog')
+    root.geometry("%dx%d%+d%+d" % (275, 25, 50, 50))
+    flist = PyShellFileList(root)
+
+    def run():
+        ClassBrowser(flist, name, [dir])
+
+    Button(root, text='ClassBrowser', command=run,).pack()
     if sys.stdin is sys.__stdin__:
-        mainloop()
-
+            root.mainloop()
+    
 if __name__ == "__main__":
+    """Run the dialog"""
     main()
diff -r 5e05d7d3db9c Lib/idlelib/TreeWidget.py
--- a/Lib/idlelib/TreeWidget.py	Sat Mar 01 07:53:28 2014 -0500
+++ b/Lib/idlelib/TreeWidget.py	Sun Mar 02 20:12:09 2014 +0530
@@ -357,6 +357,9 @@
     def OnDoubleClick(self):
         """Called on a double-click on the item."""
 
+    def FormatArgumentList(self):
+        """Return formatted non-Nonetype arguments in argument list"""
+
 
 # Example application