private void StartPrinterSearch()
{
DiscoveryHandlerImplementation discoveryHandler = new DiscoveryHandlerImplementation();
try
{
DependencyService.Get <IConnectionManager>().FindBluetoothPrinters(discoveryHandler);
}
catch (NotImplementedException)
{
Device.BeginInvokeOnMainThread(async() =>
{
await Application.Current.MainPage.DisplayAlert("Error", "Bluetooth discovery not supported on this platform", "OK");
});
}
}
private async Task DiscoverPrintersAsync()
{
await ClearDiscoveredPrinterListAsync();
await Task.Factory.StartNew(() => {
viewModel.IsPrinterListRefreshing = true;
});
Device.BeginInvokeOnMainThread(async() => {
await AnimateRefreshIconAsync();
});
await Task.Factory.StartNew(() => {
try {
List <DiscoveredPrinter> usbDriverPrinters = DependencyService.Get <IConnectionManager>().GetZebraUsbDriverPrinters();
foreach (DiscoveredPrinter printer in usbDriverPrinters)
{
Device.BeginInvokeOnMainThread(() => {
viewModel.DiscoveredPrinterList.Add(printer); // ListView view model operations must be done on UI thread due to iOS issues when clearing list while item is selected: https://forums.xamarin.com/discussion/19114/invalid-number-of-rows-in-section
});
}
} catch (Exception) {
// Do nothing
}
try {
DiscoveryHandlerImplementation usbDiscoveryHandler = new DiscoveryHandlerImplementation(this);
DependencyService.Get <IConnectionManager>().GetZebraUsbDirectPrinters(usbDiscoveryHandler);
while (!usbDiscoveryHandler.IsFinished)
{
Thread.Sleep(100);
}
} catch (Exception) {
// Do nothing
}
DiscoveryHandlerImplementation networkDiscoveryHandler = new DiscoveryHandlerImplementation(this);
NetworkDiscoverer.LocalBroadcast(networkDiscoveryHandler);
while (!networkDiscoveryHandler.IsFinished)
{
Thread.Sleep(100);
}
if (Device.RuntimePlatform != Device.WPF || DependencyService.Get <IPlatformHelper>().IsWindows10())
{
try {
DiscoveryHandlerImplementation bluetoothDiscoveryHandler = new DiscoveryHandlerImplementation(this);
DependencyService.Get <IConnectionManager>().FindBluetoothPrinters(bluetoothDiscoveryHandler);
while (!bluetoothDiscoveryHandler.IsFinished)
{
Thread.Sleep(100);
}
} catch (Exception) {
// Do nothing
}
}
});
await Task.Factory.StartNew(() => {
viewModel.IsPrinterListRefreshing = false;
});
ViewExtensions.CancelAnimations(RefreshIcon);
}
private async void DiscoverPrintersButton_Clicked(object sender, EventArgs eventArgs)
{
SetInputEnabled(false);
try {
ClearDiscoveredPrinters();
DiscoveryHandlerImplementation discoveryHandler = new DiscoveryHandlerImplementation(this);
await Task.Factory.StartNew(() => {
switch (GetSelectedDiscoveryMethod())
{
case DiscoveryMethod.LocalBroadcast:
NetworkDiscoverer.LocalBroadcast(discoveryHandler);
break;
case DiscoveryMethod.DirectedBroadcast:
NetworkDiscoverer.DirectedBroadcast(discoveryHandler, IpAddressEntry.Text);
break;
case DiscoveryMethod.MulticastBroadcast:
if (string.IsNullOrWhiteSpace(NumberOfHopsEntry.Text))
{
throw new ArgumentException("Number of hops must not be empty");
}
try {
NetworkDiscoverer.Multicast(discoveryHandler, int.Parse(NumberOfHopsEntry.Text));
} catch (FormatException) {
Device.BeginInvokeOnMainThread(async() => {
await DisplayAlert("Format Error", "Number of hops must be an integer", "OK");
});
} finally {
SetInputEnabled(true);
}
break;
case DiscoveryMethod.SubnetSearch:
if (string.IsNullOrWhiteSpace(SubnetRangeEntry.Text))
{
throw new ArgumentException("Subnet range must not be empty");
}
NetworkDiscoverer.SubnetSearch(discoveryHandler, SubnetRangeEntry.Text);
break;
case DiscoveryMethod.ZebraUsbDrivers:
try {
foreach (DiscoveredPrinter printer in DependencyService.Get <IConnectionManager>().GetZebraUsbDriverPrinters())
{
Device.BeginInvokeOnMainThread(() => {
discoveredPrinters.Add(printer);
});
}
} catch (NotImplementedException) {
Device.BeginInvokeOnMainThread(async() => {
await DisplayAlert("Error", "USB driver discovery not supported on this platform", "OK");
});
} finally {
SetInputEnabled(true);
}
break;
case DiscoveryMethod.UsbDirect:
try {
DependencyService.Get <IConnectionManager>().GetZebraUsbDirectPrinters(discoveryHandler);
} catch (NotImplementedException) {
Device.BeginInvokeOnMainThread(async() => {
await DisplayAlert("Error", "USB direct discovery not supported on this platform", "OK");
});
} finally {
SetInputEnabled(true);
}
break;
case DiscoveryMethod.FindPrintersNearMe:
NetworkDiscoverer.FindPrinters(discoveryHandler);
break;
case DiscoveryMethod.FindAllBluetoothDevices:
try {
DependencyService.Get <IConnectionManager>().FindBluetoothPrinters(discoveryHandler);
} catch (NotImplementedException) {
Device.BeginInvokeOnMainThread(async() => {
await DisplayAlert("Error", "Bluetooth discovery not supported on this platform", "OK");
});
} finally {
SetInputEnabled(true);
}
break;
}
});
} catch (Exception e) {
await DisplayAlert("Error", e.Message, "OK");
SetInputEnabled(true);
}
}
