Flutter 3.0：在 flutter 中添加和使用 marquee 插件后出现错误

Question

我添加跑马灯插件并使用后，总是出现这个错误

../../../development/flutter/.pub-cache/hosted/pub.dartlang.org/fading_edge_scrollview-2.0.1/lib/src/fading_edge_scrollview.dart:195:20: Warning: Operand of null-aware operation '?.' has type 'WidgetsBinding' which excludes null.
 - 'WidgetsBinding' is from 'package:flutter/src/widgets/binding.dart' ('../../../development/flutter/packages/flutter/lib/src/widgets/binding.dart').
    WidgetsBinding.instance?.let((it) {
                   ^
../../../development/flutter/.pub-cache/hosted/pub.dartlang.org/fading_edge_scrollview-2.0.1/lib/src/fading_edge_scrollview.dart:220:20: Warning: Operand of null-aware operation '?.' has type 'WidgetsBinding' which excludes null.
 - 'WidgetsBinding' is from 'package:flutter/src/widgets/binding.dart' ('../../../development/flutter/packages/flutter/lib/src/widgets/binding.dart').
    WidgetsBinding.instance?.removeObserver(this);

我删除了插件并删除了选取框，应用程序运行没有错误。跑马灯插件有问题吗？

Answer 1

不幸的是，Flutter 3.0.0 对某些属性的可空性进行了一些更改。

仍在积极开发的最常见的软件包发布了更新版本以支持它。

fading_edge_scrollview 似乎是这里（还）没有更新版本的那个。我不知道它是否正在积极开发中。

您可以尝试自己创建并修复它，或者您可以忽略警告。因为它实际上只是一个警告。即使出现这些警告，您的应用仍应正常运行。

Flutter 3.0：在 flutter 中添加和使用 marquee 插件后出现错误

Flutter 3.0 : Getting error after adding and using the marquee plugin in flutter

flutter

mobile

plugins

marquee