几年来，我使用这个简单的代码来读取和操作Swift:中的列表
if (Helper.hasSubscription()) {
self.allVisitedTrackHandles = Database.getAllCompletedTrackHandles(withDeleted: false, userid: self.userid)
if (self.allVisitedTrackHandles.count > 0) {
var counter = 0
for th: TrackHandle in self.allTrackHandles {
if self.allVisitedTrackHandles.contains(where: { $0.trackid == th.trackid }) {
for thv: TrackHandle in self.allVisitedTrackHandles {
if thv.trackid == th.trackid {
self.allTrackHandles[counter].date_in_milliseconds = thv.date_in_milliseconds
break
}
}
self.allTrackHandles[counter].visited = 1
}
counter += 1
}
}
}
在将我的iOS设备更新到iOS 14.4.2后，应用程序在以下行崩溃：
for th: TrackHandle in self.allTrackHandles
Xcode给我的唯一反馈是：线程79:EXC_BAD_ACCESS(代码=1，地址=0x12f100010(
我不知道为什么那条线会突然崩溃；所显示的代码中没有任何内容会导致崩溃。你在其他地方更新数组吗？这可能是线程问题吗？
您可以重构此代码，使其更简单、更清晰、更高效。这可能会有所帮助；
if Helper.hasSubscription() {
self.allVisitedTrackHandles = Database.getAllCompletedTrackHandles(withDeleted: false, userid: self.userid)
if !self.allVisitedTrackHandles.isEmpty {
for index in 0..<self.allTrackHandles.count {
if let visited = self.allVisitedTrackHandles.first { $0.track id == self.allTrackHandles[index].track id } {
self.allTrackHandles[index].date_in_milliseconds = visited.date_in_milliseconds
}
self.allTrackHandles[index].visited = 1
}
}
}