我正在尝试制作一个玩具秒表应用程序，以学习本机。 I made a lap system, but it is getting way too slow when there are >15 laps. I think the poor performance point is the laps: this.state.laps.concat([d - this.state.lapTimerStart]) part, because of .concat is making a new object eve...

每当我回到主屏幕时，都会遇到此错误，并尝试了所有操作，因为我读到此错误与“平面列表”有关，所以我尝试更改keyExtractor = {（item，index）=> index.toString（）}，但它也不起作用。 How I can fix the following error: Encountered two children with the same key, %s. Keys should be unique so that components maintain their identit...