换成这个了
ScaffoldMessenger.of(context).showSnackBar( SnackBar( content: Text("Incremented"), duration: Duration(milliseconds: 300), ), );
Demo如下
IconButton(
icon: const Icon(Icons.markunread_sharp),
onPressed: () {
Clipboard.setData(ClipboardData(text: ''));
ScaffoldMessenger.of(context)
.showSnackBar(const SnackBar(content: Text("复制成功")));
},
),