iOS 7.1 UITableView layoutSubviews 问题

Question

我正在开发一个必须同时支持 iOS 8 和 iOS 7.1 的项目。现在我遇到了一个只出现在 iOS 7.1 上但在 iOS 8 上正常工作的问题。我有一个 ViewController，它包含一个 tableview 和一个 tableHeaderView 中的自定义视图。我将发布代码如下。所有约束都是以编程方式添加的。

//视图控制器。

-(void)viewDidLoad
{
  [super viewDidLoad];

  self.commentsArray = [NSMutableArray new];

  [self.commentsArray addObject:@"TEST"];
  [self.commentsArray addObject:@"TEST"];
  [self.commentsArray addObject:@"TEST"];
  [self.commentsArray addObject:@"TEST"];
  [self.commentsArray addObject:@"TEST"];
  [self.commentsArray addObject:@"TEST"];

  [self.view addSubview:self.masterTableView];

  self.masterTableView.tableHeaderView = self.detailsView;

  [self.view setNeedsUpdateConstraints];


}

- (void)viewWillAppear:(BOOL)animated
{
  [super viewWillAppear:animated];
  [self.view layoutIfNeeded];
}


//Table view getter
- (UITableView *)masterTableView
{
  if(!_masterTableView)
  {
    _masterTableView = [UITableView new];
    _masterTableView.translatesAutoresizingMaskIntoConstraints = NO;

    _masterTableView.backgroundColor                = [UIColor greyColor];

    _masterTableView.delegate                       = self;
    _masterTableView.dataSource                     = self;

    _masterTableView.separatorStyle                 = UITableViewCellSeparatorStyleNone;
    _masterTableView.showsVerticalScrollIndicator   = NO;
    _masterTableView.separatorInset                 = UIEdgeInsetsZero;

  }

  return _masterTableView;
}

-(void)updateViewConstraints
{
 NSDictionary *views = @{
      @"table"        : self.masterTableView,
      @"details"      : self.detailsView,
 };


  NSDictionary *metrics = @{
                            @"width"  : @([UIScreen mainScreen].applicationFrame.size.width)
                            };
    //Table view constraints
    [self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|-0-[table]-0-|" options:0 metrics:0 views:views]];
    [self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-0-[table]-0-|" options:0 metrics:0 views:views]];

  //Details View
  [self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:|-0-[details(width)]-0-|" options:0 metrics:metrics views:views]];
  [self.view addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-0-[details]-0-|" options:0 metrics:metrics views:views]];

}


//Details View Getter
- (DetailsView *)detailsView
{
  if(!_detailsView)
  {

   _detailsView = [[DetailsView alloc]initWithFrame:CGRectMake(0, 0, 0, 100)];
    _detailsView.backgroundColor = [UIColor orangeColor];

  return _detailsView;
}

现在细节视图包含一些基本的子视图，它们都派生自 UIView，细节视图本身派生自更通用的超类。我将发布代码如下。

//Parent View 
@interface ParentView (): UIView

- (instancetype)init
{
  self = [super init];

  if (self)
  {
    [self setupViews];
  }

  return self;
}


- (void)setupViews
{
  [self addSubview:self.publishedTimeView];
}

- (void)updateConstraints
{
  NSDictionary *views = @{
                          @"time"         : self.publishedTimeView,
                          };


  // Header with published video time
  [self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"H:[time]-10-|" options:0 metrics:0 views:views]];
  [self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:[time(11)]" options:0 metrics:0 views:views]];

  [super updateConstraints];
}

//Getter for the timePublished view added to the detail view. Will not post all its related code for //the sake of brevity.
- (TimePublishedDetailView *)publishedTimeView
{
  if(!_publishedTimeView)
  {
    _publishedTimeView = [TimePublishedDetailView new];
    _publishedTimeView.translatesAutoresizingMaskIntoConstraints = NO;
  }

  return _publishedTimeView;
}

//Child View (or the detailsView) of the view controller.

@interface DetailsView : ParentView


@implementation RecordingDetailsView

- (void)updateConstraints
{
  NSDictionary *views = @{
                          @"time"         : self.publishedTimeView,
                          };

   //Vertical alignment of all views

  [self addConstraints:[NSLayoutConstraint constraintsWithVisualFormat:@"V:|-20-[time]" options:0 metrics:nil views:views]];

  [super updateConstraints];

}


- (void)setModel:(DetailViewModel *)model
{
  self.publishedTimeView.date = model.dateTime;

  [self setNeedsUpdateConstraints];
  [self layoutSubviews];
}

现在在 iOS 8 上看起来像这样：

但是在 iOS 7.1 上，这将崩溃并显示以下错误消息：

“异常：执行-layoutSubviews后仍然需要自动布局。UITableView的-layoutSubviews实现需要调用super”

我已经用谷歌搜索了这个并在我的布局调用中使用了代码，看看我是否可以解决这个问题，但到目前为止还没有成功。如果有人可以就如何解决此问题发布一些提示或建议，我将不胜感激。

Answer 1

我知道这个问题很老，但我最近遇到了类似的问题，经过大量谷歌搜索、尝试和失败后，我在 this answer 的帮助和一些更改下使它工作。

只需将此类别添加到您的项目中并仅调用一次[UITableView fixLayoutSubviewsMethod];（我建议在AppDelegate 内）。

#import <objc/runtime.h>
#import <objc/message.h>

@implementation UITableView (FixUITableViewAutolayoutIHope)

+ (void)fixLayoutSubviewsMethod
{
    Method existing = class_getInstanceMethod(self, @selector(layoutSubviews));
    Method new = class_getInstanceMethod(self, @selector(_autolayout_replacementLayoutSubviews));

    method_exchangeImplementations(existing, new);
}

- (void)_autolayout_replacementLayoutSubviews
{
    [super layoutSubviews];
    [self _autolayout_replacementLayoutSubviews]; // not recursive due to method swizzling
    [super layoutSubviews];
}

@end