WebView Pdf

WebViewExtended.cs

 public class WebViewExtended : WebView {
        public static BindableProperty TotalPagesProperty =
            BindableProperty.Create (nameof (TotalPages), typeof (int), typeof (WebViewExtended));

        public int TotalPages {
            get => (int) GetValue (TotalPagesProperty);
            set => SetValue (TotalPagesProperty, value);
        }

        public static BindableProperty CurrentPageProperty =
            BindableProperty.Create (nameof (CurrentPage), typeof (int), typeof (WebViewExtended));

        public int CurrentPage {
            get => (int) GetValue (CurrentPageProperty);
            set => SetValue (CurrentPageProperty, value);
        }
    }

WebViewExtendedRenderer.Android.cs

//Android
//Just add Pdf.js in assets folder and name its folder PdfViewer

public class WebViewExtendedRenderer : WebViewRenderer {
        public WebViewExtendedRenderer (Context context) : base (context) {

        }
        private readonly string _documentsPath = Environment.GetFolderPath (Environment.SpecialFolder.MyDocuments);
        private string _pdfPath;
        private readonly string _pdfFileName = "thePDFDocument.pdf";
        private string _pdfFilePath;
        private readonly WebClient _webClient = new WebClient ();

        protected override void OnElementChanged (ElementChangedEventArgs<WebView> e) {
            base.OnElementChanged (e);

            var settings = Control.Settings;
            settings.JavaScriptEnabled = true;
            settings.AllowFileAccessFromFileURLs = true;
            settings.AllowUniversalAccessFromFileURLs = true;
            settings.BuiltInZoomControls = true;
            settings.DefaultZoom = WebSettings.ZoomDensity.Far;
            Control.SetWebChromeClient (new WebChromeClient ());

            DownloadPdfDocument ();
        }

        private void DownloadPdfDocument () {
            _pdfPath = _documentsPath + "/PDFView";
            _pdfFilePath = Path.Combine (_pdfPath, _pdfFileName);

            // Check if the PDFDirectory Exists
            if (!Directory.Exists (_pdfPath)) {
                Directory.CreateDirectory (_pdfPath);
            } else {
                // Check if the pdf is there, If Yes Delete It. Because we will download the fresh one just in a moment
                if (File.Exists (_pdfFilePath)) {
                    File.Delete (_pdfFilePath);
                }
            }

            // This will be executed when the pdf download is completed
            _webClient.DownloadDataCompleted += OnPdfDownloadCompleted;
            // Lets downlaod the PDF Document
            var url = new Uri (Control.Url);
            _webClient.DownloadDataAsync (url);
        }

        private void OnPdfDownloadCompleted (object sender, DownloadDataCompletedEventArgs e) {
            try {
                // Okay the download's done, Lets now save the data and reload the webview.
                var pdfBytes = e.Result;
                File.WriteAllBytes (_pdfFilePath, pdfBytes);

                Control.LoadUrl ("file:///android_asset/PdfViewer/index.html?file=" + _pdfFilePath);
            } catch (Exception ep) {
                Console.WriteLine (ep);
            }

        }
    }

WebViewExtendedRenderer.iOS.cs

 //iOS
 public class WebViewExtendedRenderer : WkWebViewRenderer {
        protected override void OnElementChanged (VisualElementChangedEventArgs e) {
            base.OnElementChanged (e);
            if (NativeView != null && e.NewElement != null) {
                if (!(NativeView is WKWebView wKWebView))
                    return;
                BackgroundColor = Colors.Gray.ToUIColor ();
                ScrollView.Scrolled += ScrollViewOnScrolled;
                ScrollView.BackgroundColor = Color.Gray.ToUIColor ();
                wKWebView.BackgroundColor = Color.Gray.ToUIColor ();
            }
        }
//Get current page 
        void ScrollViewOnScrolled (object sender, EventArgs e) {
            HidePageNumberView (this);
            GetPages (this);
        }

        void GetPages (UIView view) {
            if (!view.Subviews.Any ()) return;
            foreach (var subView in view.Subviews) {
                if (subView is UILabel label) {
                    if (!(Element is WebViewExtended webViewExtended)) return;
                    var text = label.Text;
                    if (!string.IsNullOrEmpty (text)) {
                        if (text.Length > text.LastIndexOf (" ", StringComparison.Ordinal))
                            webViewExtended.TotalPages =
                            Convert.ToInt32 (text.Substring (text.LastIndexOf (" ", StringComparison.Ordinal))
                                .Trim ());
                        webViewExtended.CurrentPage = Convert.ToInt32 (text.Substring (0,
                                text.IndexOf (" ", StringComparison.Ordinal))
                            .Trim ());
                    }
                } else GetPages (subView);
            }
        }

        void HidePageNumberView (UIView view) {
            foreach (var subView in view.Subviews) {
                if (subView.Description.Contains ("Backdrop")) {
                    subView.Hidden = true;
                } else {
                    HidePageNumberView (subView);
                }
            }
        }
    }