How to Add a Dropdown Box in Google Spreadsheet

Google spreadsheet does not support dropdown control. But, here is a workaround solution to add the dropdown in google spreadsheet:

Step 1:
Add the entries for the dropdown in a column in worksheet. I wanted a dropdown which lists all the months for the current year. I created a separate worksheet called " Config " and entered all the months in "Month" column. This column will act as a dropdown control for us.

Step 2:
Now in the target worksheet, I have a month column and wanted a feature to be able to pick a month from the dropdown . This is how I got my month column in the target worksheet working:
- Select the column for which you want the dropdown to show up for each cell in the column
- Select "Data->Validation" from the Google Docs menu
- In the "Cell Range" section, you should see the cell range for the column you selected (target column)
- From the "Criteria" dropdown select "Item from a list" entry
- Select "Create a list from range" radio button and the range section next to the radio button enter the cell range for the dropdown list (source). In my case I had the entries for the month dropdown in a separate worksheet and the cell range was like this: " Config !B2:B13"
- Leave other default settings as it is and save the data validation

Step 3:
Now go to your target column and select one of the cell. You should see the dropdown list at the right side of the cell.