New Demos - Multiple windows design patterns

DemoPrograms/Demo_Design_Pattern_Multiple_Windows1.py

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+"""
+    PySimpleGUI The Complete Course
+    Lesson 7 - Multiple Windows
+"""
+import PySimpleGUI as sg
+
+# Design pattern 1 - First window does not remain active
+
+layout = [[ sg.Text('Window 1'),],
+          [sg.Input(do_not_clear=True)],
+          [sg.Text('', key='_OUTPUT_')],
+          [sg.Button('Launch 2')]]
+
+win1 = sg.Window('Window 1').Layout(layout)
+win2_active=False
+while True:
+    ev1, vals1 = win1.Read(timeout=100)
+    if ev1 is None:
+        break
+    win1.FindElement('_OUTPUT_').Update(vals1[0])
+
+    if ev1 == 'Launch 2' and not win2_active:
+        win2_active = True
+        win1.Hide()
+        layout2 = [[sg.Text('Window 2')],
+                   [sg.Button('Exit')]]
+
+        win2 = sg.Window('Window 2').Layout(layout2)
+        while True:
+            ev2, vals2 = win2.Read()
+            if ev2 is None or ev2 == 'Exit':
+                win2.Close()
+                win2_active = False
+                win1.UnHide()
+                break