Ios 在导航栏中将动态大小的“标题视图”居中，而不使用自动布局

我不熟悉iOS布局，我正试图以编程方式将自定义视图（实际上是一个React Native

RCTrotView

，它扩展了

UIView

，如果相关的话），它具有固有大小的动态内容（在javascript中定义）

我见过解决方案覆盖

intrinsicallySizedContent

，但这似乎只与自动布局相关，而RN不使用自动布局。我能够测量

rcrootview

内容大小的唯一方法是将其添加到视图中，然后等待几次

layoutSubViews

，直到其

frame

具有大小。这使我做出了以下努力：

尝试：在LayoutSubView中包装并设置包装大小 我正在另一个

UIView

中包装

rcrootview

，并试图覆盖

layoutSubViews

，一旦我有了本机内容的大小，就设置包装框的大小

我的包装被创建并添加到My

UIViewController

中的导航栏中，如下所示：

  RCTBridge *bridge = ((RCTRootView*)self.view).bridge;
  RCTRootView *reactView = [[RCTRootView alloc] initWithBridge:bridge moduleName:navBarCustomView initialProperties:initialProps];
  RCCCustomTitleView *titleView = [[TitleWrapperView alloc] initWithFrame:self.navigationController.navigationBar.bounds subView:reactView];
  self.navigationItem.titleView = titleView;
  self.navigationItem.titleView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin;

#import "TitleWrapperView.h"
#import <React/RCTRootView.h>

@interface TitleWrapperView ()
@property (nonatomic, strong) RCTRootView *subView;
@end

@implementation TitleWrapperView // Extends UIView

-(instancetype)initWithFrame:(CGRect)frame subView:(RCTRootView*)subView {
    self = [super initWithFrame:frame];
    
    if (self) {
        self.subView = subView;
        self.subView.sizeFlexibility = RCTRootViewSizeFlexibilityWidthAndHeight;
        self.clipsToBounds = true;

        // Prevent the wrapper from being so large initially as to squash the '< Back' button down to '<'
        self.frame = CGRectZero;

        [self addSubview:subView];
    }
    
    return self;
}

-(void)layoutSubviews {
    [super layoutSubviews];
    CGRect contentViewFrame = self.subView.contentView.frame;
    if (contentViewFrame.size.width > 0) {
        // Once we have a measurement for the sub-view's content, set the wrapper's frame
        if (self.frame.size.width != contentViewFrame.size.width) {
            self.frame = contentViewFrame;
        }
    }
}
@end

包装器的实现方式如下：

  RCTBridge *bridge = ((RCTRootView*)self.view).bridge;
  RCTRootView *reactView = [[RCTRootView alloc] initWithBridge:bridge moduleName:navBarCustomView initialProperties:initialProps];
  RCCCustomTitleView *titleView = [[TitleWrapperView alloc] initWithFrame:self.navigationController.navigationBar.bounds subView:reactView];
  self.navigationItem.titleView = titleView;
  self.navigationItem.titleView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin;

#import "TitleWrapperView.h"
#import <React/RCTRootView.h>

@interface TitleWrapperView ()
@property (nonatomic, strong) RCTRootView *subView;
@end

@implementation TitleWrapperView // Extends UIView

-(instancetype)initWithFrame:(CGRect)frame subView:(RCTRootView*)subView {
    self = [super initWithFrame:frame];
    
    if (self) {
        self.subView = subView;
        self.subView.sizeFlexibility = RCTRootViewSizeFlexibilityWidthAndHeight;
        self.clipsToBounds = true;

        // Prevent the wrapper from being so large initially as to squash the '< Back' button down to '<'
        self.frame = CGRectZero;

        [self addSubview:subView];
    }
    
    return self;
}

-(void)layoutSubviews {
    [super layoutSubviews];
    CGRect contentViewFrame = self.subView.contentView.frame;
    if (contentViewFrame.size.width > 0) {
        // Once we have a measurement for the sub-view's content, set the wrapper's frame
        if (self.frame.size.width != contentViewFrame.size.width) {
            self.frame = contentViewFrame;
        }
    }
}
@end

#导入“titleRapperView.h”
#进口
@接口标题RapperView（）
@属性（非原子，强）RCTRootView*子视图；
@结束
@实现标题rapperview//扩展UIView
-（instancetype）initWithFrame:（cRect）框架子视图：（RCTRootView*）子视图{
self=[super initWithFrame:frame]；
如果（自我）{
self.subView=子视图；
self.subView.sizeFlexibility=rctrootviewsizeflexibilitywidthandhight；
self.clipstobunds=true；
//防止包装器最初太大，以至于将“