How to suppress alert message that appears when tapping on hyperlink in Xamarin.Android PDF Viewer?
The alert message that appears when a hyperlink is clicked can be suppressed by setting the `HyperlinkClickedEventArgs.Handled` property to `true` inside the handler method of the `HyperlinkClicked` event. This will prevent the clicked hyperlink from being opened. So, it must be opened at the application level using the `HyperlinkClickedEventArgs.Uri` property. Refer to the following code snippets.
Portable
Include an interface that defines the method to open the clicked hyperlink.
C#
namespace DisableAlertDemo
{
public interface IOpenURL
{
void OpenURL(string url);
}
}
Define the handler method for the HyperlinkClicked event. In the handler method, set the HyperlinkClickedEventArgs.Handled property to true and call the method to open hyperlinks using DependencyService.
C#
public partial class MainPage : ContentPage
{
public MainPage()
{
InitializeComponent();
Stream fileStream = typeof(MainPage).GetTypeInfo().Assembly.GetManifestResourceStream("DisableAlertDemo.Assets.HTTP_Succinctly.pdf");
pdfViewerControl.LoadDocument(fileStream);
pdfViewerControl.HyperlinkClicked += PdfViewerControl_HyperlinkClicked;
}
private void PdfViewerControl_HyperlinkClicked(object sender, Syncfusion.SfPdfViewer.XForms.HyperlinkClickedEventArgs args)
{
// Block the alert message and URL navigation
args.Handled = true;
// Open the URL from the application
DependencyService.Get<IOpenURL>().OpenURL(args.Uri);
}
}
Android
Add a new static class with a static property to the Android project.
C#
// Static class to store the context of the MainActivity
internal static class ContextHelper
{
internal static Context context;
}
To open the URL, store the context of the MainActivity in the static property inside the OnCreate method of the activity.
C#
ContextHelper.context = ApplicationContext;
Implement the IOpenURL interface in Android.
C#
// Register the Android implementation of IOpenURL with DependencyService
[assembly:Xamarin.Forms.Dependency(typeof(OpenURLAndroid))]
namespace DisableAlertDemo.Droid
{
class OpenURLAndroid : IOpenURL
{
public void OpenURL(string url)
{
Context context = ContextHelper.context;
string annotationUri = url;
Uri outURI;
// Check whether the given URL is in valid format
if (Uri.TryCreate(Uri.UnescapeDataString(annotationUri), UriKind.Absolute, out outURI) || Uri.TryCreate("http://" + annotationUri, UriKind.Absolute, out outURI))
{
var uri = global::Android.Net.Uri.Parse(annotationUri);
var intent = new Intent(Intent.ActionView, uri);
intent.SetFlags(ActivityFlags.NewTask);
global::Android.Content.PM.PackageManager packageManager = context.PackageManager;
if (intent.ResolveActivity(packageManager) != null)
{
context.StartActivity(intent);
}
}
}
}
}
iOS
Implement the IOpenURL interface in the iOS.
C#
// Register the iOS implementation of IOpenURL with DependencyService
[assembly:Dependency(typeof(OpenURLiOS))]
namespace DisableAlertDemo.iOS
{
class OpenURLiOS : IOpenURL
{
public void OpenURL(string url)
{
string urlAnnotation = url;
Uri outURI;
// Check whether the URL is in valid format
if (Uri.TryCreate(Uri.UnescapeDataString(urlAnnotation), UriKind.Absolute, out outURI) || Uri.TryCreate("http://" + urlAnnotation, UriKind.Absolute, out outURI))
{
UriBuilder builder = new UriBuilder(outURI);
UIApplication.SharedApplication.OpenUrl(new NSUrl(builder.ToString()));
}
}
}
}
UWP
Implement the IOpenURL interface in the UWP.
C#
// Register the UWP implementation of IOpenURL with DependencyService
[assembly:Dependency(typeof(OpenURLWindows))]
namespace Syncfusion.SfPdfViewer.XForms.UWP
{
class OpenURLWindows : IOpenURL
{
public async void OpenURL(string url)
{
Uri outURI;
// Check whether the URL is in valid format
if (Uri.TryCreate(Uri.UnescapeDataString(url), UriKind.Absolute, out outURI) || Uri.TryCreate("http://" + url, UriKind.Absolute, out outURI))
{
UriBuilder builder = new UriBuilder(url);
await Windows.System.Launcher.LaunchUriAsync(builder.Uri);
}
}
}
}
Sample link
