I've been trying for hours to send a form to a printing service for both Android and iOS, something I have absolutely no experience with. I've seen https://forums.xamarin.com/discussion/42417/printing-on-ipad-from-webview which, I thought, sent me on the right path but this prints a WebView control. In my case, I want to print a ContentPage.
As an alternative, I thought of creating a HtmlWebViewSource that would generate the equivalent view of the information I want to print, but again, it doesn't work. My main issue is to go from Xamarin.Forms.WebView to (lets say) Android.Webkit.WebView to access the CreatePrintDocumentAdapter()
In my form, I have:
private void OnPrint()
{
var WebViewSource = new HtmlWebViewSource()
{
Html =
"<html>" +
"<body>" +
"Hello world" +
"</body>" +
"</html>"
};
var WebView = new WebView() { Source = WebViewSource };
DependencyService.Get<IPrintService>().Print(WebView);
}
IPrintService is
public interface IPrintService
{
void Print(WebView webView);
}
and my DependencyService is
[assembly: Dependency(typeof(PrintService))]
namespace Whatever.ApplicationLayer.Droid
{
public class PrintService : IPrintService
{
public void Print(WebView webView)
{
var PrintManager = (PrintManager)Forms.Context.GetSystemService(Context.PrintService);
var AndroidWebView = (Android.Webkit.WebView)webView.On<Xamarin.Forms.PlatformConfiguration.Android>();
var JobName = "Test";
PrintManager.Print(JobName, AndroidWebView.CreatePrintDocumentAdapter(JobName), null);
}
}
}
When it's time to cast webView, it dies ("System.InvalidCastException: Specified cast is not valid.") What am I doing wrong? What am I missing?