Migrate 104-complete to NNBD. #211
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
rami-a
approved these changes
Oct 16, 2020
| super(key: key, listenable: listenable); | ||
|
|
||
| final Animation<double> _listenable; |
There was a problem hiding this comment.
Why was the type changed and no longer using the super's listenable anymore?
There was a problem hiding this comment.
Super's listenable has type Listenable.
In this widget, listenable is used as an Animation<double> for its value, so listenable must be an Animation<double>. Animation<double> is a subclass of Listenable.
If we use super's listenable, then we must do a casting similar to
final Animation<double> animation = this.listenable; on line 77 (before the change).
This also permits the user to pass in any Listenable, including ones that don't have a value, which breaks the widget. By restricting listenable to Animation<double>, we can ensure that the animation passed in by the user is valid, and all errors can be caught at compile-time.
JoseAlba
approved these changes
Oct 16, 2020
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
No description provided.