How to use Application.Top in the xlwings API way

The Application object in Excel’s object model represents the entire Excel application, and through xlwings’ API, we can control many high-level settings and behaviors. Here, we focus on some of its most frequently used members for automation and customization.

1. Application.ScreenUpdating

• Functionality: Controls whether screen updates occur while a macro runs. Turning it off can significantly speed up code execution by preventing the screen from refreshing.
• Syntax: app.screen_updating = boolean_value
• boolean_value: True to enable screen updates (default), False to disable.
• Example:

import xlwings as xw
app = xw.App(visible=False) # Start Excel in background
app.screen_updating = False # Disable updates
# Perform operations like writing large data
wb = app.books.add()
wb.sheets[0].range('A1').value = [[1, 2], [3, 4]]
app.screen_updating = True # Re-enable updates
wb.save('output.xlsx')
wb.close()
app.quit()

2. Application.Calculation

• Functionality: Sets the calculation mode for Excel, such as automatic, manual, or semi-automatic, which is useful when working with large workbooks to control when formulas recalc.
• Syntax: app.calculation = mode_value
• mode_value: Can be 'automatic', 'manual', or 'semiautomatic'. In xlwings, these correspond to Excel’s constants.
• Example:

import xlwings as xw
app = xw.App()
wb = app.books.open('data.xlsx')
app.calculation = 'manual' # Set to manual calculation
# Change values without triggering recalc
wb.sheets[0].range('B1').value = 100
app.calculate() # Manually trigger calculation
result = wb.sheets[0].range('C1').value # Get calculated result
print(result)
wb.close()
app.quit()

3. Application.DisplayAlerts

• Functionality: Determines whether Excel displays alert messages (e.g., save prompts). Disabling alerts allows for smoother automated processes.
• Syntax: app.display_alerts = boolean_value
• boolean_value: True to show alerts, False to suppress them.
• Example:

import xlwings as xw
app = xw.App()
app.display_alerts = False # Suppress alerts
wb = app.books.open('temp.xlsx')
wb.close() # No prompt to save changes
app.display_alerts = True # Restore alerts
app.quit()

4. Application.Visible

• Functionality: Controls the visibility of the Excel application window. Hiding Excel can be useful for running scripts in the background.
• Syntax: app.visible = boolean_value
• boolean_value: True to make Excel visible, False to hide.
• Example:

import xlwings as xw
app = xw.App(visible=False) # Start hidden
# Perform operations without showing UI
wb = app.books.add()
wb.sheets[0].range('A1').value = 'Hidden Process'
wb.save('hidden_output.xlsx')
app.visible = True # Show Excel to user
wb.close()
app.quit()

5. Application.Version

• Functionality: Returns the version number of Excel, which can be helpful for compatibility checks.
• Syntax: app.version
• This is a read-only property returning a string.
• Example:

import xlwings as xw
app = xw.App()
version = app.version
print(f"Excel version: {version}") # e.g., '16.0' for Office 2016
if version.startswith('16'):
    print("Compatible with Office 2016+ features.")
app.quit()