flutter - Hive.box ('box_name').listenable()get，在null上调用 `The method ' toSet'，在flutter上出错

Question

当我尝试使用here is an example on web Hive.box('box_name')。listenable()时，如果没有键，则会发生错误；

════════ Exception caught by widgets library ═══════════════════════════════════
The following NoSuchMethodError was thrown building FutureBuilder<dynamic>(dirty, state: _FutureBuilderState<dynamic>#566bb):
The method 'toSet' was called on null.
Receiver: null
Tried calling: toSet()

The relevant error-causing widget was
    FutureBuilder<dynamic> 
package:hive_benchmark/sketcpad/sketchpad.dart:109
When the exception was thrown, this was the stack
#0      Object.noSuchMethod  (dart:core-patch/object_patch.dart:53:5)
#1      BoxX.listenable 
package:hive_flutter/src/box_extensions.dart:11
#2      _DrawingScreenState.build.<anonymous closure> 
package:hive_benchmark/sketcpad/sketchpad.dart:120
#3      _FutureBuilderState.build 
package:flutter/…/widgets/async.dart:732
#4      StatefulElement.build 
package:flutter/…/widgets/framework.dart:4619
...
════════════════════════════════════════════════════════════════════════════════

Answer 1

由于hive_flutter: ^0.3.0+2只是升级了依赖项，因此已解决此问题