1. Create an enumeration: Create an enumeration in Mendix that represents the months (e.g., "January," "February," etc.). This enumeration will be used as the data source for the dropdown selection.
2. Add a dropdown to the page: Place a dropdown widget on your page and configure it to use the month enumeration as its data source.
3. Retrieve data based on the selected month: In the microflow associated with the page, retrieve the data for the selected month. Use a retrieve action to fetch the data based on a filter that matches the selected month.
4. Update the DataGrid: Bind the DataGrid widget to the retrieved data entity. Configure the DataGrid's data source to display the filtered data based on the selected month.
5. Update the DataGrid upon dropdown selection: Set up an event listener for the dropdown widget's "on change" event. In the microflow or nanoflow associated with this event, re-retrieve the data based on the newly selected month and update the DataGrid accordingly.