Major update of all demo programs to use new PEP8 bindings, etc

DemoPrograms old/Demo_Design_Patterns.py

@@ -0,0 +1,54 @@
+"""
+When creating a new PySimpleGUI program from scratch, start here.
+These are the accepted design patterns that cover the two primary use cases
+
+1. A "One Shot" window
+2. A persistent window that stays open after button clicks (uses an event loop)
+3. A persistent window that need to perform Update of an element before the window.read
+"""
+# ---------------------------------#
+# DESIGN PATTERN 1 - Simple Window #
+# ---------------------------------#
+import PySimpleGUI as sg
+
+layout = [[ sg.Text('My Oneshot') ],
+          [ sg.Button('OK') ]]
+
+window = sg.Window('My Oneshot', layout)
+event, values = window.read()
+window.close()
+
+
+# -------------------------------------#
+# DESIGN PATTERN 2 - Persistent Window #
+# -------------------------------------#
+import PySimpleGUI as sg
+
+layout = [[ sg.Text('My layout') ],
+          [ sg.Button('OK'), sg.Button('Cancel') ]]
+
+window = sg.Window('Design Pattern 2', layout)
+
+while True:     # Event Loop
+    event, values = window.read()
+    if event in (None, 'Cancel'):
+        break
+window.close()
+
+# ------------------------------------------------------------------#
+# DESIGN PATTERN 3 - Persistent Window with "early update" required #
+# ------------------------------------------------------------------#
+import PySimpleGUI as sg
+
+layout = [[ sg.Text('My layout', key='-TEXT-KEY-') ],
+          [ sg.Button('OK'), sg.Button('Cancel') ]]
+
+window = sg.Window('Design Pattern 3', layout, finalize=True)
+
+window['-TEXT-KEY-'].Update('NEW Text')     # Change the text field. Finalize allows us to do this
+
+while True:     # Event Loop
+    event, values = window.read()
+    if event in (None, 'Cancel'):
+        break
+window.close()