I believe you want to capture the button clicked action insider your coach behavior tab. If my assumptions is right then you can capture the button action in "change" tab as follows
- Take a config option ex- buttonA, type- Boolean.
- Bind with the button also map the config variable in parent coach where this coach view has been used.
- Now in change tab event.property will capture the config option name (here buttonA) if the button is clicked.