详细说明iOS11、iPhone X、Xcode9 适配向导_IOS

// 有些界面以下使用代理方法来设置，发现并没有生效
- (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section;
- (CGFloat)tableView:(UITableView *)tableView heightForFooterInSection:(NSInteger)section;

// 这样的原理是因为之前只是实现了高度的代理方法，却没有实现View的代理方法，iOS10及以前这么写是没问题的，iOS11开启了行高估算机制引起的bug，因此有以下几种解决方法：

// 解决方法一：添加实现View的代理方法
- (UIView *)tableView:(UITableView *)tableView viewForFooterInSection:(NSInteger)section {
  return nil;
}
- (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section {
  return nil;
}

// 解决方法二：直接使用tableView属性进行设置,修复该UI错乱
self.tableView.sectionHeaderHeight = 0;
self.tableView.sectionFooterHeight = 5;

[_optionTableView setContentInset:UIEdgeInsetsMake(-35, 0, 0, 0)];

// 解决方法三：添加以下代码关闭估算行高
self.tableView.estimatedRowHeight = 0;
self.tableView.estimatedSectionHeaderHeight = 0;
self.tableView.estimatedSectionFooterHeight = 0;

// A view controller that will be shown inside of a navigation controller can assign a UISearchController to this property to display the search controller's search bar in its containing navigation controller's navigation bar.
@property (nonatomic, retain, nullable) UISearchController *searchController API_AVAILABLE(ios(11.0)) API_UNAVAILABLE(tvos);

// If this property is true (the default), the searchController's search bar will hide as the user scrolls in the top view controller's scroll view. If false, the search bar will remain visible and pinned underneath the navigation bar.

// 测试代码
#import <objc/runtime.h>
NSMutableString *resultStr = [NSMutableString string];
//获取指定类的Ivar列表及Ivar个数
unsigned int count = 0;
Ivar *member = class_copyIvarList([[application valueForKeyPath:@"_statusBar"] class], &count);
  
for(int i = 0; i < count; i++){
  Ivar var = member[i];
  //获取Ivar的名称
  const char *memberAddress = ivar_getName(var);
  //获取Ivar的类型
  const char *memberType = ivar_getTypeEncoding(var);
  NSString *str = [NSString stringWithFormat:@"key = %s       type = %s \n",memberAddress,memberType];
   [resultStr appendString:str];
}
NSLog(@"%@", resultStr);

// 其他版本的手机
key = _inProcessProvider      type = @"<UIStatusBarStateProvider>"
key = _showsForeground       type = B
key = _backgroundView        type = @"UIStatusBarBackgroundView"
key = _doubleHeightLabel      type = @"UILabel"
key = _doubleHeightLabelContainer  type = @"UIView"
key = _currentDoubleHeightText   type = @"NSString"
key = _currentRawData        type = {超长。。}
key = _interruptedAnimationCompositeViews type = @"NSMutableArray"
key = _newStyleBackgroundView    type = @"UIStatusBarBackgroundView"
key = _newStyleForegroundView    type = @"UIStatusBarForegroundView"
key = _slidingStatusBar       type = @"UIStatusBar"
key = _styleAttributes       type = @"UIStatusBarStyleAttributes"
key = _waitingOnCallbackAfterChangingStyleOverridesLocally type = B
key = _suppressGlow         type = B
key = _translucentBackgroundAlpha  type = d
key = _showOnlyCenterItems     type = B
key = _foregroundViewShouldIgnoreStatusBarDataDuringAnimation type = B
key = _tintColor          type = @"UIColor"
key = _lastUsedBackgroundColor   type = @"UIColor"
key = _nextTintTransition      type = @"UIStatusBarStyleAnimationParameters"
key = _overrideHeight        type = @"NSNumber"
key = _disableRasterizationReasons type = @"NSMutableSet"
key = _timeHidden          type = B
key = _statusBarWindow       type = @"UIStatusBarWindow"

// iPhone X
key = _statusBar ; type = @"_UIStatusBar"

// 因此可见iPhone X的状态栏是多嵌套了一层，多取一次即可，最终适配代码为：
NSArray *children;
// 不能用 [[self deviceVersion] isEqualToString:@"iPhone X"] 来判断，因为模拟器不会返回 iPhone X
  if ([[application valueForKeyPath:@"_statusBar"] isKindOfClass:NSClassFromString(@"UIStatusBar_Modern")]) {
    children = [[[[application valueForKeyPath:@"_statusBar"] valueForKeyPath:@"_statusBar"] valueForKeyPath:@"foregroundView"] subviews];
  } else {
    children = [[[application valueForKeyPath:@"_statusBar"] valueForKeyPath:@"foregroundView"] subviews];
  }