1. Add the highlighted code to the Click event for the Hello button (it appends the word 'Hello ' to the #STD_TEXT field):
#STD_TEXT:= #STD_TEXT + 'Hello '
The AutoComplete prompter shows up as you start to type. You can use it to select a command and the command's parameter values. It also completes parameter values as you type them.
Note that there is a space between the word Hello and the closing quote.
Please review the points noted in Some Things to Note about Entering Code.