是否可以使用Timer而不是执行异步步骤Future.delayed?主要原因是类cancel()中方法的可用性Timer,它允许我在 Flutter 中处理小部件时取消正在运行的计时器。
import 'dart:async';
const kFirstStepDuration = Duration(seconds: 1);
const kSecondStepDuration = Duration(seconds: 1);
const kThirdStepDuration = Duration(seconds: 1);
void main() async{
await Future.delayed(kFirstStepDuration);
print('first step');
await Future.delayed(kSecondStepDuration);
print('second step');
await Future.delayed(kThirdStepDuration);
print('end');
}
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使用 Richard Heap 答案后的计时器,我想尽可能取消这些步骤,但下面的代码提示:
first timer to begin
cancel first
cancel second
cancel third
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我的期望是提示:
first timer to begin
cancel first
second timer to begin
cancel second
third timer to begin
cancel third
executed in 0:00:00.06000
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import …Run Code Online (Sandbox Code Playgroud)