Latest updates from Tony

ProgrammingClassExamples/MacOS versions/5a PSG (listboxes add remove).py

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+#PySimple examples (v 3.9)
+#Tony Crewe
+#Oct 2018 MacOs
+
+import PySimpleGUI as sg
+
+#sg.ChangeLookAndFeel('BlueMono')
+sg.SetOptions (background_color = 'LightBlue',
+            element_background_color = 'LightBlue',
+            text_element_background_color = 'LightBlue',
+               font = ('Calibri', 14, 'bold'),
+               text_color = 'Black',
+               input_text_color ='Black',
+               button_color = ('Black', 'White'))
+
+#use column feature with height listbox takes up
+column1 = [
+    [sg.Text('Add or Delete Items\nfrom a Listbox')],
+     [sg.InputText( size = (15,1), key = 'add'), sg.ReadButton('Add', size = (5,1))],
+    [sg.ReadButton('Delete selected entry', size = (18,1))]]
+
+#initial listbox entries
+List = ['Austalia', 'Canada', 'Greece']         
+
+#add initial List  to listbox
+layout = [
+    [sg.Listbox(values=[l for l in List], size = (20,8), key ='_listbox_'),
+     sg.Column(column1)]]
+
+window = sg.Window('Listbox').Layout(layout)
+
+while True:
+    button, value = window.Read()
+    if button is not None:
+        #value[listbox] returns a list
+        #using value[listbox][0] gives the string
+        if button == 'Delete selected entry':
+            #ensure something is selected
+            if value['_listbox_'] == []:               
+                sg.Popup('Error','You must select a Country')
+            else:
+                #find and remove this
+                List.remove(value['_listbox_'][0])  
+        if button == 'Add':
+            #add string in add box to list
+            List.append(value['add'])          
+        List.sort()                         
+        #update listbox
+        window.FindElement('_listbox_').Update(List)
+    else:
+        break