Support Send SMS message textbox toggle.
If true, the textbox will be displayed on the state editor. The content of the textbox will be used as the header in the SMS menu message. For example, if the content of the textbox is "Transactions:" then the menu will be shown as follow.
Transactions:
1. 26 Jan 2012 09:16 - USD 10.00 Pay cab
2. 26 Jan 2012 10:10 - USD 3.45 Starbucks
3. 26 Jan 2012 12:25 - USD 20.00 Lunch
4. 26 Jan 2012 13:30 - USD 3.00 Starbucks
9: More
0: Exit
Subclass has the option to turn it off by override this method.