我正在创建一个简单的桌面视图应用程序来显示和播放所有iOS系统声音。
我以[ID(Int):Name(String)]的形式将所有的声音和ID都放在一个字典中(我现在意识到这是一个不好的方法),问题是当我加载我的视图时它加载得很好,但如果我向下滚动最初在顶部更改的单元格。从底部滚动到顶部时相同。
例如,视图加载,我可以点击并听到我点击的任何单元格中的各种声音。让我们说第一个单元格是" SMS-Sound1"秒数是" SMS-Sound2"。现在,当我向下滚动到那些单元格不在视图的位置,然后向后滚动到顶部时,它们被命名为不同的东西(仍然来自我的数据字典)。
如何解决此问题,以便加载tableview,然后tableview数据不会更改?
编辑:我认为问题可能是for for循环执行了大约300,000次,但事实并非如此,制作了一个IDS数组,所以它只执行了大约1000次,问题仍然存在< / p>
我的代码:
单元格设置
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("soundCell", forIndexPath: indexPath)
let button = cell.viewWithTag(3) as! UILabel //UILabel in "SoundCell"
for i: Int in 999..<4100 {
//Lowest id sound is 1000, highest is 4095
if (sounds[i] != nil) && loadedSoundStrings.contains(sounds[i]!) == false {
button.text = sounds[i]
loadedSoundStrings.append(sounds[i]!)
cell.tag = i
break
}
}
return cell
}
行/部分
override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
return 1
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return sounds.count
}
变量:
let sounds =
[ 1000:"new-mail.caf",
1001:"mail-sent.caf",
1002:"Voicemail.caf",
1003:"ReceivedMessage.caf",
1004:"SentMessag.caf",
1005:"alarm.caf",
1006:"low-power.caf",
1007:"sms-received1.caf",
1008:"sms-received2.caf",
1009:"sms-received3.caf",
1010:"sms-received4.caf",
1011:"-(SMSReceived_Vibrate)",
1012:"sms-received1.caf",
1013:"sms-received5.caf",
1014:"sms-received6.caf",
1015:"Voicemail.caf",
1016:"tweet_sent.caf",
1020:"Anticipate.caf",
1021:"Bloom.caf",
1022:"Calypso.caf",
1023:"Choo_Choo.caf",
1024:"Descent.caf",
1025:"Fanfare.caf",
1026:"Ladder.caf",
1027:"Minuet.caf",
1028:"News_Flash.caf",
1029:"Noir.caf",
1030:"Sherwood_Forest.caf",
1031:"Spell.caf",
1032:"Suspense.caf",
1033:"Telegraph.caf",
1034:"Tiptoes.caf",
1035:"Typewriters.caf",
1036:"Update.caf",
1050:"ussd.caf",
1051:"SIMToolkitCallDropped.caf",
1052:"SIMToolkitGeneralBeep.caf",
1053:"SIMToolkitNegativeACK.caf",
1054:"SIMToolkitPositiveACK.caf",
1055:"SIMToolkitSMS.caf",
1057:"Tink.caf",
1070:"ct-busy.caf",
1071:"ct-congestion.caf",
1072:"ct-path-ack.caf",
1073:"ct-error.caf",
1074:"ct-call-waiting.caf",
1075:"ct-keytone2.caf",
1100:"lock.caf",
1101:"unlock.caf",
1102:"-(FailedUnlock)",
1103:"Tink.caf",
1104:"Tock.caf",
1105:"Tock.caf",
1106:"beep-beep.caf",
1107:"RingerChanged.caf",
1108:"photoShutter.caf",
1109:"shake.caf",
1110:"jbl_begin.caf",
1111:"jbl_confirm.caf",
1112:"jbl_cancel.caf",
1113:"begin_record.caf",
1114:"end_record.caf",
1115:"jbl_ambiguous.caf",
1116:"jbl_no_match.caf",
1117:"begin_video_record.caf",
1118:"end_video_record.caf",
1150:"vc~invitation-accepted.caf",
1151:"vc~ringing.caf",
1152:"vc~ended.caf",
1153:"ct-call-waiting.caf",
1154:"vc~ringing.caf",
1200:"dtmf-0.caf",
1201:"dtmf-1.caf",
1202:"dtmf-2.caf",
1203:"dtmf-3.caf",
1204:"dtmf-4.caf",
1205:"dtmf-5.caf",
1206:"dtmf-6.caf",
1207:"dtmf-7.caf",
1208:"dtmf-8.caf",
1209:"dtmf-9.caf",
1210:"dtmf-star.caf",
1211:"dtmf-pound.caf",
1254:"long_low_short_high.caf",
1255:"short_double_high.caf",
1256:"short_low_high.caf",
1257:"short_double_low.caf",
1258:"short_double_low.caf",
1259:"middle_9_short_double_low.caf",
1300:"Voicemail.caf",
1301:"ReceivedMessage.caf",
1302:"new-mail.caf",
1303:"mail-sent.caf",
1304:"alarm.caf",
1305:"lock.caf",
1306:"Tock.caf",
1307:"sms-received1.caf",
1308:"sms-received2.caf",
1309:"sms-received3.caf",
1310:"sms-received4.caf",
1311:"-(SMSReceived_Vibrate)",
1312:"sms-received1.caf",
1313:"sms-received5.caf",
1314:"sms-received6.caf",
1315:"Voicemail.caf",
1320:"Anticipate.caf",
1321:"Bloom.caf",
1322:"Calypso.caf",
1323:"Choo_Choo.caf",
1324:"Descent.caf",
1325:"Fanfare.caf",
1326:"Ladder.caf",
1327:"Minuet.caf",
1328:"News_Flash.caf",
1329:"Noir.caf",
1330:"Sherwood_Forest.caf",
1331:"Spell.caf",
1332:"Suspense.caf",
1333:"Telegraph.caf",
1334:"Tiptoes.caf",
1335:"Typewriters.caf",
1336:"Update.caf",
1350:"-(RingerVibeChanged)",
1351:"-(SilentVibeChanged)",
4095:"-(Vibrate)"]
var loadedSoundStrings = [String]()
答案 0 :(得分:0)
如果我正确理解你的代码,那你就是错误的做法。你有一个加载一次的声音字典。 cellForRowAtIndexPath
函数应返回一个tableViewCell,其中包含一个声音的详细信息。
UITableView
会自动丢弃屏幕外的单元格以节省内存,并将其重新用于新显示的单元格。这就是你致电dequeueReusableCellWithIdentifier
的原因。因此,您应该这样做:
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("soundCell", forIndexPath: indexPath)
let button = cell.viewWithTag(3) as! UILabel //UILabel in "SoundCell"
//Lowest id sound is 1000, highest is 4095
let i = indexPath.row + 1000
button.text = sounds[i]
cell.tag = i
return cell
}
由于您正在对声音编号范围进行硬编码,所以我也做了同样的事情。
答案 1 :(得分:0)
表视图最适合数组,因为数组具有已定义的顺序,您可以快速访问给定元素; cellForRowAtIndexPath
中的for循环很少是好事。
但是,你有几个问题,因为你的声音标识符不是从0开始,你不能使用标识符作为数组的直接索引,但标识符也不是顺序的,所以你可以甚至使用简单的偏移量(为行号添加一个常量值)。
我认为最好的解决方案不是像你的字典一样直接依赖内在类型,而是为每个声音创建一个结构并存储它们的数组。像这样:
class MyViewController: UIViewController, UITableViewDelegate, UITableViewDatasource
struct Sound {
var id:Int
var fileName:String
}
var sounds=[Sound]()
func loadSounds() {
let soundsDict =
[1000:"new-mail.caf",
1001:"mail-sent.caf",
1002:"Voicemail.caf",
1003:"ReceivedMessage.caf",
1004:"SentMessag.caf",
1005:"alarm.caf",
1006:"low-power.caf",
1007:"sms-received1.caf",
1008:"sms-received2.caf",
...
]
for (id,fileName) in soundsDict {
self.sounds.append(Sound(id: id, fileName: fileName))
}
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("soundCell", forIndexPath: indexPath)
let button = cell.viewWithTag(3) as! UILabel //UILabel in "SoundCell"
button.text=self.sounds[indexPath.row].fileName
return cell
}
override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
return 1
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return self.sounds.count
}
}
答案 2 :(得分:0)
当您实际想要仅为加载的行实例化声音时,您正在实例化每一行的所有声音。要修复订单问题,请更改您的订单
cellForRowAtIdexPath
到此:
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("soundCell", forIndexPath: indexPath)
let button = cell.viewWithTag(3) as! UILabel //UILabel in "SoundCell"
button.text = sounds[i]
cell.tag = indexPath.row
return cell
}
由于您将NumberOfRowsInSection设置为sounds.count,因此每个单元格会发出1个声音。对于您拥有的每个声音,都会调用行的单元格。