There are 3 tabs in a tabbedpanel, a TextField component is in the first tab,
and several form components in the other tabs for user input. I added a save
button in the tabbedpanel(instead add 3 buttons in each tab, because I just
want to save all user inputs by one click), my question is, how
there are 6 options in a RadioChoice, when user selects different option,
different containner will be displayed to user. In my understanding, when user
clicks on the different option, it should display a black point to tell user
which option he/she selects. But why there is no black point in
