DEV/flutter_flutter
1
0
Fork 0
mirror of https://github.com/flutter/flutter.git synced 2026-02-20 02:29:02 +08:00
Code Issues Packages Projects Releases Wiki Activity

Merge pull request #1698 from abarth/set_state_error

Browse Source 
Provide a better error for setState on a defunct State
This commit is contained in:
Adam Barth 2016-02-08 21:10:32 -08:00
commit 8fdaf4af49
1 changed files with 15 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
packages/flutter/lib/src/widgets/framework.dart
View File

@ -334,7 +334,21 @@ abstract class State<T extends StatefulComponent> {
/// component will not be scheduled for rebuilding, meaning that its rendering
/// will not be updated.
void setState(VoidCallback fn) {
assert(_debugLifecycleState != _StateLifecycle.defunct);
assert(() {
if (_debugLifecycleState == _StateLifecycle.defunct) {
throw new WidgetError(
'setState() called after dipose(): $this\n'
'This error happens if you call setState() on State object for a widget that\n'
'no longer appears in the widget tree (e.g., whose parent widget no longer\n'
'includes the widget in its build). This error can occur when code calls\n'
'setState() from a timer or an animation callback. The preferred solution is\n'
'to cancel the timer or stop listening to the animation in the dispose()\n'
'callback. Another solution is to check the "mounted" property of this\n'
'object before calling setState() to ensure the object is still in the tree.'
);
}
return true;
});
fn();
_element.markNeedsBuild();
}