Matt's examples

1 files changed, 47 insertions, 0 deletions

diff --git a/Demo/tkinter/matt/entry-with-shared-variable.py b/Demo/tkinter/matt/entry-with-shared-variable.py
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+++ b/Demo/tkinter/matt/entry-with-shared-variable.py
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+from Tkinter import *
+import string 
+
+# This program  shows how to make a typein box shadow a program variable.
+
+class App(Frame):
+    def __init__(self, master=None):
+	Frame.__init__(self, master)
+	self.pack()
+
+	self.entrythingy = Entry()
+	self.entrythingy.pack()
+
+	self.button = Button(self, {"text" : "Uppercase The Entry", "command" : self.upper})
+	self.button.pack()
+
+	
+	# here we have the text in the entry widget tied to a variable.
+	# changes in the variable are echoed in the widget and vice versa. 
+	# Very handy.
+	# there are other Variable types. See Tkinter.py for all
+	# the other variable types that can be shadowed
+	self.contents = StringVar()
+	self.contents.set("this is a variable")
+	self.entrythingy.config({"textvariable":self.contents})
+
+	# and here we get a callback when the user hits return. we could
+	# make the key that triggers the callback anything we wanted to.
+	# other typical options might be <Key-Tab> or <Key> (for anything)
+	self.entrythingy.bind('<Key-Return>', self.print_contents)
+
+    def upper(self):
+	# notice here, we don't actually refer to the entry box.
+	# we just operate on the string variable and we 
+        # because it's being looked at by the entry widget, changing
+	# the variable changes the entry widget display automatically.
+	# the strange get/set operators are clunky, true...
+	str = string.upper(self.contents.get())
+	self.contents.set(str)
+
+    def print_contents(self, event):
+	print "hi. contents of entry is now ---->", self.contents.get()
+
+root = App()
+root.master.title("Foo")
+root.mainloop()
+