Flutter won't rebuild a text - flutter

Question

In my app, I have some (youtube)links, which always have the text value of "Link", but their tap launch parameter is different as the content of the page is changing.
I recognized that the app first builds these links with the initial correct value, then, upon changes, they won't get updated.
RichText _createExerciseLink(String url) {
return new RichText(
text: new TextSpan(
children: [
new TextSpan(
text: Translate.of(context).trans("exercise.link"),
recognizer: new TapGestureRecognizer()
..onTap = () {
print("Launcihng: ${url}");
launch(url);
},
),
],
),
);
}
But, if I change the text "link" to the corresponding HTTP link then it gets rerendered...
RichText _createExerciseLink(String url) {
return new RichText(
text: new TextSpan(
children: [
new TextSpan(
text: url,
recognizer: new TapGestureRecognizer()
..onTap = () {
print("Launcihng: ${url}");
launch(url);
},
),
],
),
);
}
I assume this is some kind of a caching mechanism?
Is there any way to force to recreate the whole widget?

Answer 1

Seems like adding a Key is the trick here:
Parent widget:
Key key = new Key(link);
...
link != null ? _createExerciseLink(link, key) : Container(),
and in the text:
RichText _createExerciseLink(String url, Key key) {
return new RichText(
key: key,
text: new TextSpan(
children: [
new TextSpan(
text: Translate.of(context).trans("exercise.link"),
recognizer: new TapGestureRecognizer()
..onTap = () {
print("Launcihng: ${url}");
launch(url);
},
),
],
),
);
}