【发布时间】：2017-06-21 20:56:12
【问题描述】：
为了提高 UITableView 的性能，我正在考虑将 UITableViewCell 的所有设置重新定位到 cellForRowAtIndexPath 之外。
此时，我的 tableview 中有几个自定义单元格，我在 cellForRowAtIndexPath 中设置了这些单元格。但正因为如此，每次我在表格视图中滚动时，每次必须在屏幕上显示一个单元格时，都会再次完成设置，导致延迟。
我尝试通过为我的单元格使用类变量将设置放入 viewDidLoad 中，但没有任何效果。你知道我可以在哪里移动我所有的单元格的设置，尤其是如果可能的话？
提前致谢，祝您有美好的一天！
编辑： 如所问，这是我的 cellForRowAtIndexPathMethod ：
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
NSString *CellIdentifier = [menuItems objectAtIndex:indexPath.row];
cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
cell.delegate = self;
if ([appliedTheme hasPrefix:@"DarkMode"]) {
self.tableView.backgroundColor = [UIColor colorWithRed:0.20 green:0.20 blue:0.20 alpha:1.0];
cell.backgroundColor = [UIColor colorWithRed:0.20 green:0.20 blue:0.20 alpha:1.0];
cell.cardView.backgroundColor = [UIColor colorWithRed:0.30 green:0.30 blue:0.30 alpha:1.0];
cell.webServerIntroLabel.textColor = [UIColor whiteColor];
cell.webServerOptionsTitle.textColor = [UIColor whiteColor];
cell.webServerOptionsReachableAtLabel.textColor = [UIColor whiteColor];
}else {
self.tableView.backgroundColor = [UIColor colorWithRed:0.92 green:0.92 blue:0.92 alpha:1.0];
cell.backgroundColor = [UIColor colorWithRed:0.92 green:0.92 blue:0.92 alpha:1.0];
cell.cardView.backgroundColor = [UIColor whiteColor];
cell.webServerIntroLabel.textColor = [UIColor blackColor];
cell.webServerOptionsTitle.textColor = [UIColor blackColor];
cell.webServerOptionsReachableAtLabel.textColor = [UIColor blackColor];
}
if ([CellIdentifier isEqualToString:@"webServerIntro"]) {
cell.webServerIntroImageView.image = [UIImage imageNamed:webServerIntroIconToShow];
cell.webServerIntroLabel.adjustsFontSizeToFitWidth = YES;
cell.webServerIntroLabel.numberOfLines = 0;
[cell.webServerIntroLabel sizeToFit];
cell.webServerIntroLabel.text = @"Some text";
}else if ([CellIdentifier isEqualToString:@"webServerOptions"]) {
cell.webServerOptionsTitle.adjustsFontSizeToFitWidth = YES;
cell.webServerOptionsTitle.text = NSLocalizedString(@"Web Server Options", nil);
cell.webServerOptionsStatusLabel.adjustsFontSizeToFitWidth = YES;
if (!webServerStarted) {
cell.webServerOptionsImageView.image = [UIImage imageNamed:@"Not-Checked"];
cell.webServerOptionsStatusLabel.text = NSLocalizedString(@"Not Running", nil);
cell.serverURLLabel.text = NSLocalizedString(@"Not Reachable", nil);
cell.ipAddressURLLabel.text = NSLocalizedString(@"Not Reachable", nil);
[cell.startStopWebServerButton setTitle:NSLocalizedString(@"Start Web Server", nil) forState:UIControlStateNormal];
cell.webServerStartedBool = NO;
}else {
NSString *serverURL = [self deviceName];
serverURL = [serverURL stringByReplacingOccurrencesOfString:@" " withString:@"-"];
cell.webServerOptionsImageView.image = [UIImage imageNamed:@"Checked"];
cell.webServerOptionsStatusLabel.text = NSLocalizedString(@"Running", nil);
cell.serverURLLabel.text = [NSString stringWithFormat:@"http://%@.local", serverURL];
cell.ipAddressURLLabel.text = [NSString stringWithFormat:@"%@", webUploader.serverURL];
[cell.startStopWebServerButton setTitle:NSLocalizedString(@"Stop Web Server", nil) forState:UIControlStateNormal];
cell.webServerStartedBool = YES;
}
cell.webServerOptionsStatusLabel.textColor = [UIColor lightGrayColor];
cell.webServerOptionsReachableAtLabel.adjustsFontSizeToFitWidth = YES;
cell.webServerOptionsReachableAtLabel.text = NSLocalizedString(@"Reachable At :", nil);
cell.ipAddressURLLabel.adjustsFontSizeToFitWidth = YES;
cell.ipAddressURLLabel.textColor = [UIColor lightGrayColor];
cell.ipAddressURLLabel.layer.borderWidth = 1.0f;
cell.ipAddressURLLabel.layer.borderColor = [[UIColor lightGrayColor] CGColor];
cell.ipAddressURLLabel.layer.cornerRadius = 5;
cell.serverURLLabel.adjustsFontSizeToFitWidth = YES;
cell.serverURLLabel.textColor = [UIColor lightGrayColor];
cell.serverURLLabel.layer.borderWidth = 1.0f;
cell.serverURLLabel.layer.borderColor = [[UIColor lightGrayColor] CGColor];
cell.serverURLLabel.layer.cornerRadius = 5;
cell.startStopWebServerButton.layer.borderWidth = 1.0f;
cell.startStopWebServerButton.layer.borderColor = [[UIColor clearColor] CGColor];
cell.startStopWebServerButton.layer.cornerRadius = 5;
cell.startStopWebServerButton.titleLabel.adjustsFontSizeToFitWidth = YES;
if ([appliedTheme isEqualToString:@"Default-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0 green:0.478 blue:0.875 alpha:1]; /*#007ADF : Bleu iOS*/
}else if ([appliedTheme isEqualToString:@"Red-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.90 green:0.07 blue:0.00 alpha:1.0]; /*#E61100 : Rouge*/
}else if ([appliedTheme isEqualToString:@"Orange-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.83 green:0.33 blue:0.00 alpha:1.0]; /*#D35400 : Orange*/
}else if ([appliedTheme isEqualToString:@"Yellow-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.95 green:0.61 blue:0.07 alpha:1.0]; /*#F39C12 : Jaune*/
}else if ([appliedTheme isEqualToString:@"Green-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.15 green:0.68 blue:0.38 alpha:1.0]; /*#27AE60 : Vert*/
}else if ([appliedTheme isEqualToString:@"Purple-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.56 green:0.27 blue:0.68 alpha:1.0]; /*#8E44AD : Violet*/
}else if ([appliedTheme isEqualToString:@"Gray-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.74 green:0.76 blue:0.78 alpha:1.0]; /*#BDC3C7 : Gris*/
}else if ([appliedTheme isEqualToString:@"DarkGray-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.50 green:0.55 blue:0.55 alpha:1.0]; /*#7F8C8D : Gris foncé*/
}else if ([appliedTheme isEqualToString:@"DesaturatedBlue-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.17 green:0.24 blue:0.31 alpha:1.0]; /*#2C3E50 : Bleu désaturé*/
}else if ([appliedTheme isEqualToString:@"VeryDarkGray-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.20 green:0.20 blue:0.20 alpha:1.0]; /*#333333 : Gris très foncé*/
}else if ([appliedTheme isEqualToString:@"Black-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.00 green:0.00 blue:0.00 alpha:1.0]; /*#000000 : Noir*/
}else if ([appliedTheme isEqualToString:@"DarkModeDefault-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0 green:0.478 blue:0.875 alpha:1]; /*#007ADF : Bleu iOS*/
}else if ([appliedTheme isEqualToString:@"DarkModeRed-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.90 green:0.07 blue:0.00 alpha:1.0]; /*#E61100 : Rouge*/
}else if ([appliedTheme isEqualToString:@"DarkModeOrange-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.83 green:0.33 blue:0.00 alpha:1.0]; /*#D35400 : Orange*/
}else if ([appliedTheme isEqualToString:@"DarkModeYellow-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.95 green:0.61 blue:0.07 alpha:1.0]; /*#F39C12 : Jaune*/
}else if ([appliedTheme isEqualToString:@"DarkModeGreen-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.15 green:0.68 blue:0.38 alpha:1.0]; /*#27AE60 : Vert*/
}else if ([appliedTheme isEqualToString:@"DarkModePurple-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.56 green:0.27 blue:0.68 alpha:1.0]; /*#8E44AD : Violet*/
}else if ([appliedTheme isEqualToString:@"DarkModeGray-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.74 green:0.76 blue:0.78 alpha:1.0]; /*#BDC3C7 : Gris*/
}else if ([appliedTheme isEqualToString:@"DarkModeDarkGray-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.50 green:0.55 blue:0.55 alpha:1.0]; /*#7F8C8D : Gris foncé*/
}else if ([appliedTheme isEqualToString:@"DarkModeDesaturatedBlue-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.17 green:0.24 blue:0.31 alpha:1.0]; /*#2C3E50 : Bleu désaturé*/
}else if ([appliedTheme isEqualToString:@"DarkModeVeryDarkGray-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.20 green:0.20 blue:0.20 alpha:1.0]; /*#333333 : Gris très foncé*/
}else if ([appliedTheme isEqualToString:@"DarkModeBlack-Theme"]) {
cell.startStopWebServerButton.backgroundColor = [UIColor colorWithRed:0.00 green:0.00 blue:0.00 alpha:1.0]; /*#000000 : Noir*/
}
}else {
}
return cell;
}
【问题讨论】：
-
显示您的代码。
cellForRowAt应该是一个相对较小、快速的函数，因为它被多次调用。您不应在此方法中获取数据或执行复杂的计算。 -
现在可以在edit中找到代码了！
标签： ios objective-c uitableview