Latest updates from Tony

ProgrammingClassExamples/MacOS versions/7b PSG (add validation and error trap).py

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+#PySimple examples (v 3.9)
+#Tony Crewe
+#Oct 2018 MacOs
+
+import PySimpleGUI as sg
+import os                       #to work with windows OS
+
+#sg.ChangeLookAndFeel('GreenTan')
+
+sg.SetOptions(background_color = 'LightBlue',
+            element_background_color = 'LightBlue',
+            text_element_background_color = 'LightBlue',
+              font= ('Calibri', 14, 'bold'))   
+
+layout = [
+    [sg.Text('Enter a Name and four Marks')],
+    [sg.Text('Name:', size =(8,1)), sg.InputText(size = (10,1), key = '_name_')],
+     [sg.Text('Mark1:', size =(8,1)), sg.InputText(size = (5,1), key = '_m1_')],
+         [sg.Text('Mark2:', size =(8,1)), sg.InputText(size = (5,1), key = '_m2_')],
+         [sg.Text('Mark3:', size =(8,1)), sg.InputText(size = (5,1), key = '_m3_')],
+         [sg.Text('Mark4:', size =(8,1)), sg.InputText(size = (5,1), key = '_m4_')],
+    [sg.ReadButton('Save', size = (6,1),key = '_save_'),  sg.Text('Press to Save to file')],
+    [sg.ReadButton('Display',size = (6,1), key = '_display_'), sg.Text('To retrieve and Display')],
+    [sg.Multiline(size = (24,4), key = '_multiline_', pad = (2,15))]]
+
+window = sg.Window('Simple Average Finder').Layout(layout)   
+
+
+while True:
+    button, value = window.Read()   #value is a dictionary holding name and marks (4)
+    if button is not None:  
+        #initialise variables
+        total = 0.0
+        index = ''
+        name = value['_name_']
+        #get pathname to current file
+        dirname, filename = os.path.split(os.path.abspath(__file__))
+        #add desired file name for saving to path
+        pathname = os.path.join(dirname , 'results.txt' )             
+        #generic catch error - blanks or wrong data types
+        try:
+            if button == '_save_':
+                for i in range (1,5):
+                    index = '_m' + str(i) + '_'         
+
+                    #Check for values between 0 and 100
+                    if float(value[index])  < 0 or float(value[index]) >100:
+                        sg.Popup('Out of Range', 'Enter Marks between 0 and 100')
+                    else:
+                        total += float(value[index])
+                        average = total/4
+                        f = open(pathname, 'w')         
+                        print (name, file = f)
+                        print (total, file = f)
+                        print (average, file = f)
+                        f.close()
+        except ValueError:
+            sg.Popup('Error','Check entries and try again') 
+            
+        if button == '_display_':
+            #This loads the file line by line into a list called data.
+            #the strip() removes whitespaces from beginning and end of each line.
+            try:
+                data = [line.strip() for line in open(pathname)]
+                #create single string to display in multiline object.
+                string = 'Name:  ' + data[0] +'\nTotal:  ' + str(data[1]) + '\nAverage:  ' + str(data[2])
+                window.FindElement('_multiline_').Update(string)
+            except:
+                sg.PopupError('Error', 'Problem finding or reading file') 
+    else:
+        break  
+