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How to use Application.AddCustomList in the xlwings API way

The AddCustomList member of the Application object in Excel is a method that allows you to define a custom list for sorting and auto-filling data. Custom lists are particularly useful for creating personalized sorting orders, such as days of the week, months, or any user-defined sequence, which can then be applied across worksheets to ensure consistent data organization. In xlwings, this functionality is accessed through the api property, which provides direct access to the underlying Excel object model, enabling precise control over Excel’s features from Python.

Functionality:
The primary function of AddCustomList is to add a new custom list to Excel’s memory. Once added, this list can be used in sorting operations or for auto-fill actions, where dragging a cell’s fill handle will populate cells based on the defined sequence. This is beneficial for standardizing data entry and maintaining order in datasets that follow non-alphabetical or non-numeric sequences.

Syntax in xlwings:
The xlwings API call follows the pattern:

app.api.AddCustomList(ListArray, ByRow)

• ListArray: This parameter specifies the items to be included in the custom list. It can be provided as a Python list or tuple containing strings or numbers. For example, ['Low', 'Medium', 'High'] or ('Q1', 'Q2', 'Q3', 'Q4'). The list must be one-dimensional.
• ByRow: This is a Boolean parameter that indicates whether the list is arranged by rows. In most cases, setting ByRow to False is appropriate, as custom lists are typically column-oriented. If set to True, the list is interpreted as a row-based array, but this is less common. The default behavior in Excel VBA is False, and it is generally recommended to use False in xlwings unless specific row-based data is provided.

Example Usage:
Below is an xlwings code example that demonstrates how to add a custom list and then use it for sorting data in an Excel worksheet. This example assumes an existing Excel workbook is open via xlwings.

import xlwings as xw

# Connect to the active Excel application
app = xw.apps.active

# Define a custom list for priority levels
custom_list = ['Low', 'Medium', 'High']

# Add the custom list using the Application object's AddCustomList method
app.api.AddCustomList(ListArray=custom_list, ByRow=False)

# Now, use the custom list to sort data in a specific worksheet
wb = xw.books.active
ws = wb.sheets['Sheet1']

# Assume column A contains priority data to be sorted based on the custom list
# Set the sort range (e.g., A1:A10)
sort_range = ws.range('A1:A10')

# Apply sorting with the custom order
sort_range.api.Sort(
Key1=ws.range('A1').api,
Order1=1, # Ascending order
CustomOrder=custom_list[0], # Use the first item of the list to reference the custom list
DataOption1=0
)

# Note: In Excel, the custom list is stored globally, so it can be reused across workbooks during the session.

How to use Application.ActivateMicrosoftApp in the xlwings API way

The ActivateMicrosoftApp method in the Excel object model is accessible via the Application object in xlwings. This method serves a specific purpose: it activates a separate Microsoft application window, bringing it to the foreground. This is particularly useful when automating workflows that involve switching between Excel and other Microsoft Office programs like Word or PowerPoint, allowing for seamless integration and control from within an Excel VBA macro or, in this context, an xlwings-powered Python script.

Functionality
The primary function of ActivateMicrosoftApp is to launch or switch to another Microsoft application. It does not create new documents within that application but activates the application window itself. If the requested application is not already running, the method will typically start it. This enables automated processes to prepare data in Excel and then directly present it in another Office program without manual intervention.

Syntax in xlwings
The xlwings API provides a direct mapping to this method through the Application object. The syntax is:

app.api.ActivateMicrosoftApp(Index)

Here, app refers to the xlwings App instance (which corresponds to the Excel Application object). The .api property exposes the underlying pywin32 object, allowing access to the native VBA method.

Parameters
The method requires a single argument, Index, which is a Long integer specifying the application to activate. The standard values are:

Note: The availability and behavior might depend on the specific Office version installed. Indexes like 5 (Schedule+) are largely obsolete.

Code Examples
Below are practical xlwings code snippets demonstrating the use of ActivateMicrosoftApp.

1. Activating Microsoft Word:
   This script opens Excel, writes a value to a cell, and then switches to Microsoft Word.

import xlwings as xw

# Connect to the active Excel instance or start a new one
app = xw.App(visible=True)
wb = app.books.active
wb.sheets[0].range('A1').value = "Data for Word"

# Activate Microsoft Word (Index = 1)
app.api.ActivateMicrosoftApp(1)

2. Switching to PowerPoint from an Existing Workbook:
   This example assumes Excel is already open and controlled by xlwings. It activates PowerPoint.

import xlwings as xw

# Connect to the currently running Excel
app = xw.apps.active
# Bring PowerPoint to the foreground
app.api.ActivateMicrosoftApp(2)

3. Checking Application Activation with Error Handling:
   A more robust example includes basic error handling, acknowledging that the target application might fail to start.

import xlwings as xw
import time

app = xw.App(visible=True)
try:
    # Attempt to activate Microsoft Access
    app.api.ActivateMicrosoftApp(4)
    print("Microsoft Access activation attempted.")
    # A brief pause can be helpful for the window switch to complete
    time.sleep(1)
except Exception as e:
    print(f"An error occurred: {e}")
finally:
    # Perform cleanup or other tasks
    pass