TextEditor v1

from guizero import App, Box, PushButton, TextBox, Combo, Text, info

app = App(title="Text Editor",width="800",height="600")

# Event Handlers

def btnSaveClicked():
    f =  open(txtFilename.value, "w")
    f.write(txtEditor.value)
    f.close()
    info('SAVE','Your file has been saved')

def btnLoadClicked():
    with open(txtFilename.value, "r") as f:
        txtEditor.value = f.read()

def cboBgChanged():
    boxEditor.bg = cboBg.value

def cboFontChanged():
    boxEditor.font = cboFont.value

def cboFontSizeChanged():
    boxEditor.text_size = int(cboFontSize.value)

# Your GUI widgets go here

####################################################################

boxFileControls = Box(app, align="top", width='fill', height = 30)
boxFileControls.bg = "forest green"
boxFileControls.text_color = 'white'
btnOpen = PushButton(boxFileControls, align="left", text = "Open", width = 15, command = btnLoadClicked)
btnSave = PushButton(boxFileControls, align="left", text = "Save", width = 15, command = btnSaveClicked)
txtFilename = TextBox(boxFileControls, text = 'editor.txt', width = 20, height = 'fill', align = 'right')
lblFilename = Text(boxFileControls, text = 'Filename:',align = 'right',size = 12)

####################################################################

boxMenu = Box(app, align="top", width='fill', height = 25  )
boxMenu.bg ='deep sky blue'
lblFont = Text(boxMenu, text="Font: ", color = 'black', align = 'left')
cboFont = Combo(boxMenu, options=["Palatino Linotype","Arial","Segoe UI", "Times New Roman","Courier New"], width = 20, height = 'fill', align = 'left', command = cboFontChanged)
lblBg = Text(boxMenu, text="Background: ", color = 'black', align = 'left')
cboBg = Combo(boxMenu, options=["light yellow", "linen", "honeydew", "LightBlue1", "gray98", "white"], width = 20, height = 'fill', align = 'left', command = cboBgChanged)
lblFontSize = Text(boxMenu, text="Size: ", color = 'black', align = 'left')
cboFontSize = Combo(boxMenu, options=[10,12,14,16,18], width = 20, height = 'fill', align = 'left', command = cboFontSizeChanged)

####################################################################

boxEditor = Box(app, align = 'top', width='fill', height = 'fill', border = 1)
boxEditor.bg = 'light yellow'
boxEditor.font ='Palatino Linotype'
txtEditor = TextBox(boxEditor, width = 'fill', height = 'fill', multiline = True, scrollbar = True)

####################################################################

# Show the GUI on the screen
app.display()