iOS 11导航栏/ uibarbutton项目渲染问题

Question

我尝试在左边添加多个UIBarButtonItem项，在右边添加一个。{p>这在iOS10上工作得很好，但iOS11似乎打破了它。

这都是用Xamarin编写的，但类/方法名称等几乎都是映射，所以你想要的答案。

当使用最简单的方法添加两个按钮时，直接在按钮上设置图像/动作，我只得到两个中的一个，它是巨大的，居中的，我的标题丢失了：< / p>

var leftMenuBarBackBtn = new UIBarButtonItem(UIImage.FromBundle("arrowBackButton"), UIBarButtonItemStyle.Plain, leftBackButtonTap);
var leftMenuBarItem = new UIBarButtonItem(UIImage.FromBundle("menu"), UIBarButtonItemStyle.Plain, leftMenuButtonTap);
UIBarButtonItem[] navItems = { 
    leftMenuBarBackBtn,
    leftMenuBarItem
};

var rightMenuBarItem = new UIBarButtonItem(UIImage.FromBundle("bell").ImageWithRenderingMode(UIImageRenderingMode.AlwaysOriginal), UIBarButtonItemStyle.Plain, rightMenuButtonTap);

NavigationItem.LeftItemsSupplementBackButton = false;
NavigationItem.LeftBarButtonItems = navItems;
NavigationItem.RightBarButtonItem = rightMenuBarItem;

之前我们正在创建UIImage项并将其添加为自定义视图（请忽略可怕的做法，这是继承的）：

var leftBackBtn = new UIButton(UIButtonType.Custom);
leftBackBtn.SetImage(UIImage.FromBundle("arrowBackButton").ImageWithRenderingMode(UIImageRenderingMode.AlwaysOriginal), UIControlState.Normal);
leftBackBtn.Frame = new CGRect(0, 0, 27, 20);
leftBackBtn.ContentMode = UIViewContentMode.ScaleAspectFit;
leftBackBtn.TouchUpInside += leftBackButtonTap;
UIBarButtonItem leftMenuBarBackBtn = new UIBarButtonItem(leftBackBtn);

var leftMenuBtn = new UIButton(UIButtonType.Custom);
leftMenuBtn.SetImage(UIImage.FromBundle("menu").ImageWithRenderingMode(UIImageRenderingMode.AlwaysOriginal), UIControlState.Normal);
leftMenuBtn.Frame = new CGRect(0, 0, 27, 20);
leftMenuBtn.ContentMode = UIViewContentMode.ScaleAspectFit;
leftMenuBtn.TouchUpInside += leftMenuButtonTap;
UIBarButtonItem leftMenuBarItem = new UIBarButtonItem(leftMenuBtn);
UIBarButtonItem[] navItems = { leftMenuBarBackBtn, leftMenuBarItem };

var rightMenuBtn = new UIButton(UIButtonType.Custom);
rightMenuBtn.SetImage(UIImage.FromBundle("bell").ImageWithRenderingMode(UIImageRenderingMode.AlwaysOriginal), UIControlState.Normal);
rightMenuBtn.Frame = new CGRect(0, 0, 19, 22);
rightMenuBtn.ContentMode = UIViewContentMode.ScaleAspectFit;
rightMenuBtn.TouchUpInside += rightMenuButtonTap;
UIBarButtonItem righttMenuBarItem = new UIBarButtonItem(rightMenuBtn);
UIBarButtonItem[] navItems2 = { righttMenuBarItem };

this.NavigationItem.LeftBarButtonItems = navItems;
this.NavigationItem.RightBarButtonItems = navItems2;

我得到一个奇怪的，伸展的＆＃39;回来＆＃39;按钮，以及一个非常小的汉堡菜单：

最后，虽然我不同意，但我们的客户坚持使用自定义后退按钮。当我按照我认为合适的方法进行操作时，使用原生后退按钮，它有点工作，我的标题视图又回来了。这可以作为一个止损，但它并不是我们想要的用户体验：

var leftMenuBarItem = new UIBarButtonItem(UIImage.FromBundle("menu"), UIBarButtonItemStyle.Plain, leftMenuButtonTap);
var rightMenuBarItem = new UIBarButtonItem(UIImage.FromBundle("bell").ImageWithRenderingMode(UIImageRenderingMode.AlwaysOriginal), UIBarButtonItemStyle.Plain, rightMenuButtonTap);

NavigationItem.LeftItemsSupplementBackButton = true;

NavigationItem.LeftBarButtonItem = leftMenuBarItem;
NavigationItem.RightBarButtonItem = rightMenuBarItem;

谢谢！

Answer 1

参考UIBarButtonItem on iOS 11

UIBarButtonItem使用autolayout而不是处理帧。

这就是按钮拉伸的原因。

修改：

widthConstraint = leftBackBtn.WidthAnchor.ConstraintEqualTo(27);
heightConstraint = leftBackBtn.HeightAnchor.ConstraintEqualTo(20);
widthConstraint.Active = true;
heightConstraint.Active = true;