Where can i "signal" refresh requirement of my widget ?

[buxx]

Hello,

I wrote a very basic text input here: https://github.com/buxx/rollgui/blob/master/src/ui/widget/text_input.rs

But I have a little bug: When text is larger than size, words are correctly put at the next line, but this line is invisible. If I resize window, line is visible:

What can I do to fix this ?