PROSAGA码农传奇-IOS-xamarin.forms在Android上引发的webview.focused事件，但在iOS上没有

<div class =“post-text”itemprop =“text”>
  
    的
      原因：
    </强>
  
  
    财产
     <code>
 Focus
 </code>
     在Forms中对应我们调用的方法
    <a href="https://developer.apple.com/documentation/appkit/nstextview/1807130-becomefirstresponder?language=occ" rel="nofollow noreferrer">
      becomeFirstResponder
    </A>
     在原生iOS平台上。遗憾的是，UIWebView和WKwebview不支持该方法
     <code>
 becomeFirstResponder
 </code>
    。这种方法仅适用于某些“输入控件”，例如UITextField和UITextView（表单中的条目）。即使你在一个'输入控件'上设置事件
     <code>
 webview
 </code>
    。它不适用于iOS。
  
  
    的
      解决方法：
    </强>
  
  
    你可以添加一个
     <code>
 TapGestureRecognizer
 </code>
     在webview上。你必须使用CustomRenderer来实现它。因为如果你在表单中添加TapGestureRecognizer会产生冲突。
请参阅以下代码。
  
  <BLOCKQUOTE>
    
      在表格中
    
  </BLOCKQUOTE>
   <pre>
 <code>
 public MainPage()
{
 if (Device.RuntimePlatform == "iOS")
 {

MessagingCenter.Subscribe<Object,string>(this,"webview_click", (sender,arg)=> {

// int index = Convert.ToInt16(arg));

});
   }
}

</code>
 </pre>
  <BLOCKQUOTE>
    
      在iOS中
    
  </BLOCKQUOTE>
   <pre>
 <code>
 using System;
using Foundation;
using UIKit;
using Xamarin.Forms;
using Xamarin.Forms.Platform.iOS;
using xxx;
using xxx.iOS;
using ObjCRuntime;
[assembly:ExportRenderer(typeof(WebView),typeof(MyWebViewRenderer))]
namespace xxx.iOS
{
 public class MyWebViewRenderer : WebViewRenderer, IUIGestureRecognizerDelegate
 {

public bool isFirstLoad = true;

public MyWebViewRenderer()
    {

}

protected override void OnElementChanged(VisualElementChangedEventArgs e)
    {
        base.OnElementChanged(e);

if (e != null)
        {
            UITapGestureRecognizer tap = new UITapGestureRecognizer(this, new Selector("Tap_Handle:"));
            tap.WeakDelegate = this;
            this.AddGestureRecognizer(tap);
        }

}

[Export("gestureRecognizer:shouldRecognizeSimultaneouslyWithGestureRecognizer:")]
    public bool ShouldRecognizeSimultaneously(UIGestureRecognizer gestureRecognizer, UIGestureRecognizer otherGestureRecognizer)
    {
        return true;
    }

[Export("Tap_Handle:")]
 void Tap_Handle(UITapGestureRecognizer tap)
 {
 if(isFirstLoad)
 {
 isFirstLoad = false;
 MessagingCenter.Send<Object,string>(this, "webview_click",Element.AutomationId);
 }
 }

}
}

</code>
 </pre>
</DIV>