How To Pass a Query String in Xamarin WebView Source On Navigating - xamarin

Question

I need to pass a query string into a WebView Xamarin Source on Navigating (www.websiteexmple.com?mobileapp=true).
In Android works perfect, but in IOS does not seems to work correctly sometimes . I am missing someting ?
I have notice it does not work in IOS when Net Core website needs to do some redirects : Ex: User Enter Email and click Next Step.
public void WebView_NavigatingAsync(object sender, WebNavigatingEventArgs args)
{
if (!args.Url.Contains(Source) && !args.Url.Contains("facebook") && !args.Url.Contains("google"))
{
var uri = new Uri(args.Url);
// Device.OpenUri(uri);
Launcher.OpenAsync(uri);
args.Cancel = true;
}
else
{
var src = args.Url;
string prefix = "?";
if (src.Contains("?"))
{
prefix = "&";
}
if (!args.Url.Contains("mobileapp=true"))
{
args.Cancel = true;
var webview = (WebView)sender;
webview.Source = src + prefix + "mobileapp=true";
}
}
}

Answer 1

I think there is a bug in WebView.Source for iOS, the question mark is coming encoded and the system didn't recognize the URL.
You can create a custom WebViewRender and replace %3F to ?
On iOS project create a CustomWebViewRender
[assembly: ExportRenderer(typeof(CustomWebView), typeof(CustomWebViewRenderer))]
namespace Test.iOS.Renders
{
public class CustomWebViewRenderer : WkWebViewRenderer
{
public override WKNavigation LoadRequest (NSUrlRequest request)
{
var url = request.Url.ToString().Replace("html%3F", "html?");
var dotnetURI = new System.Uri(url);
var idn = new System.Globalization.IdnMapping();
NSUrl nsURL = new NSUrl(dotnetURI.Scheme, idn.GetAscii(dotnetURI.DnsSafeHost), dotnetURI.PathAndQuery);
return base.LoadRequest(new NSUrlRequest(nsURL));
}
}
}
On Xamarin project use your custom WebView
cs file:
namespace Test.Renders
{
public class CustomWebView : WebView
{
}
}
Xaml file:
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
xmlns:test="clr-namespace:Test.Renders"
...>
<ContentPage.Content>
<StackLayout>
<test:CustomWebView x:Name="map"
HorizontalOptions="FillAndExpand"
VerticalOptions="FillAndExpand"/>
...