《iOS13的特性和适配》

Xcode11

【WWDC2019 Session】Xcode 11新特性
Xcode官方文档

iOS13的特性

众多新功能，随iOS13而来。

iOS13的适配

1. SceneDelegate

In iOS 13 and later, use UISceneDelegate objects to respond to life-cycle events in a scene-based app.
In iOS 12 and earlier, use the UIApplicationDelegate object to respond to life-cycle events.

Q: 基于Xcode11新建的工程，在iOS13以前的版本不展示window，如何解决？
A：在AppDelegate.h 中添加window:

@property (strong, nonatomic) UIWindow *window;

如果不使用场景功能，在info.plist文键中删除Application Scene Manifast。
注释掉AppDelegate中 UISceneSession lifecycle

//- (UISceneConfiguration *)application:(UIApplication *)application configurationForConnectingSceneSession:(UISceneSession *)connectingSceneSession options:(UISceneConnectionOptions *)options {
//    // Called when a new scene session is being created.
//    // Use this method to select a configuration to create the new scene with.
//    return [[UISceneConfiguration alloc] initWithName:@"Default Configuration" sessionRole:connectingSceneSession.role];
//}
//
//
//- (void)application:(UIApplication *)application didDiscardSceneSessions:(NSSet *)sceneSessions {
//    // Called when the user discards a scene session.
//    // If any sessions were discarded while the application was not running, this will be called shortly after application:didFinishLaunchingWithOptions.
//    // Use this method to release any resources that were specific to the discarded scenes, as they will not return.
//}

2. 不允许使用 `valueForKey`、`setValue: forKey` 获取和设置私有属性;

// crash代码 
[tf setValue:[UIColor greenColor] forKeyPath:@"_placeholderLabel.textColor"];
[tf setValue:[UIFont systemFontOfSize:12.f] forKeyPath:@"_placeholderLabel.font"];

// 修复代码
tf.attributedPlaceholder = [[NSMutableAttributedString alloc] initWithString:tf.placeholder attributes:@{NSFontAttributeName:[UIFont systemFontOfSize:12.f],NSForegroundColorAttributeName:[UIColor redColor]}];

(注意: 使用富文本修改placeholder时, tf.placeholder不能为空.)

// crash代码
UIButton *cancelBtn = [searchBar valueForKey:@"_cancelButton"];

// 修复代码 (不建议)
UIButton *cancelBtn = [searchBar valueForKey:@"cancelButton"];

// 获取状态栏视图 crash
UIView *statusBar = [[[UIApplication sharedApplication] valueForKey:@"statusBarWindow"] valueForKey:@"statusBar"];

3. 控制器的 `modalPresentationStyle` 新增`UIModalPresentationAutomatic`, 且在iOS13上被设置为默认值;

iOS13效果:

1). 如果使用此效果模式, 需要适配页面布局, 否则底部内容会被遮挡;
2). 如果不使用, 修改控制器的 modalPresentationStyle为其他值.
(注意: 系统类如发送短信修改style无效.)

4. 之前标记为 API_DEPRECATED 部分类被移除

MPMoviePlayerController ==> AVPlayerViewController
UISearchDisplayController ==> UISearchController
UIAlertView

5. Sign in with Apple

使用 Sign in with Apple 会更加方便、快捷、安全，苹果不会追踪用户在应用中的行为。所以，对于用户来说使用 Sign in with Apple 会更加安全。
App 没有提供第三方登录，不需要集成。如果用到了第三方登录，那么需要提供 Sign in with Apple，而且必须放在最前面。
集成 Sign in with Apple 功能.

6. 即将废弃的 LaunchImage

iOS 8 之前我们是在 LaunchImage 来设置启动图，但是随着苹果设备尺寸越来越多，我们需要在对应的 aseets 里面放入所有尺寸的启动图，这是非常繁琐的一个步骤。因此在 iOS 8 苹果引入了 LaunchScreen.storyboard，支持界面布局用的 AutoLayout + SizeClass ，可以很方便适配各种屏幕。

需要注意的是，苹果在 Modernizing Your UI for iOS 13 section 中提到
，从2020年4月开始，所有支持 iOS 13 的 App 必须提供 LaunchScreen.storyboard，否则将无法提交到 App Store 进行审批。

7. DeviceToken 获取

// 以前的
- (void)application:(UIApplication*)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData*)deviceToken {
    /// Required - 注册 DeviceToken
    [JPUSHService registerDeviceToken:deviceToken];
}

// iOS13
- (void)application:(UIApplication *)application
    didRegisterForRemoteNotificationsWithDeviceToken:(NSData *)deviceToken {
  const unsigned int *tokenBytes = [deviceToken bytes];
  NSString *tokenString = [NSString stringWithFormat:@"%08x%08x%08x%08x%08x%08x%08x%08x",
                        ntohl(tokenBytes[0]), ntohl(tokenBytes[1]), ntohl(tokenBytes[2]),
                        ntohl(tokenBytes[3]), ntohl(tokenBytes[4]), ntohl(tokenBytes[5]),
                        ntohl(tokenBytes[6]), ntohl(tokenBytes[7])];
  rootViewController.deviceTokenValueLabel.text = tokenString;
  rootViewController.deviceTokenValueLabel.textColor =
      [UIColor colorWithRed:0.0 / 255
                      green:122.0 / 255
                       blue:255.0 / 255
                      alpha:1];
  NSLog(@"Device Token: %@", tokenString);
  [JPUSHService registerDeviceToken:deviceToken];
}

https://developer.umeng.com/docs/66632/detail/126489

8. UISegmentedControl 默认样式改变

iOS13以前:

iOS13:

9. 蓝牙需要新增权限描述

iOS13 以后废弃 NSBluetoothPeripheralUsageDescription,
iOS13新增 NSBluetoothAlwaysUsageDescription;

10. 废弃UIWebview APIs

从 iOS13 开始苹果将 UIWebview 列为过期API。目前提交苹果应用市场（App Store）会反馈以下邮件提示：

ITMS-90809: Deprecated API Usage - Apple will stop accepting submissions of apps that use UIWebView APIs .
See developer.apple.com/documentati… for more information.

11. CNCopyCurrentNetworkInfo 变化

 An app that fails to meet any of the above requirements receives the following return value:

- An app linked against iOS 12 or earlier receives a dictionary with pseudo-values. In this case, the SSID is Wi-Fi (or WLAN in the China region), and the BSSID is 00:00:00:00:00:00.
- An app linked against iOS 13 or later receives NULL.

iOS13 以后只有开启了 Access WiFi Information capability，才能获取到 SSID 和 BSSID

12. Dark Mode

Apps on iOS 13 are expected to support dark mode
Use system colors and materials
Create your own dynamic colors and images Leverage flexible infrastructure

不适配暗黑模式情况下处理方式:

方法一: 修改代码
if (@available(iOS 13.0, *)) {
    [UIApplication sharedApplication].keyWindow.overrideUserInterfaceStyle = UIUserInterfaceStyleLight;
} 

方法二: 修改info.plist
UIUserInterfaceStyle
Light

UIUserInterfaceStyle

适配暗黑模式:

使用 QMUITheme 实现换肤并适配 iOS 13 Dark Mode

千里之行，始于足下。

参考文档:
【WWDC2019 Session】Xcode 11新特性
Xcode官方文档
众多新功能，随iOS13而来。
集成 Sign in with Apple 功能.
适配 iOS13（持续更新）
使用 QMUITheme 实现换肤并适配 iOS 13 Dark Mode