Ensure the same item only appears once on the list

Sample Apps/BLE Explorer/Robotics.Mobile.BtLEExplorer.Core/Pages/CharacteristicList.xaml.cs

@@ -14,6 +14,7 @@ public partial class CharacteristicList : ContentPage
  IService service; 
 
  ObservableCollection<ICharacteristic> characteristics;
+ Dictionary<Guid, ICharacteristic> guidToCharacteristic;
 
  public CharacteristicList (IAdapter adapter, IDevice device, IService service)
  {
@@ -22,6 +23,7 @@ public CharacteristicList (IAdapter adapter, IDevice device, IService service)
  this.device = device;
  this.service = service;
  this.characteristics = new ObservableCollection<ICharacteristic> ();
+ this.guidToCharacteristic = new Dictionary<Guid, ICharacteristic> ();
 
  listView.ItemsSource = characteristics;
 
@@ -31,7 +33,11 @@ public CharacteristicList (IAdapter adapter, IDevice device, IService service)
  if (characteristics.Count == 0)
  Device.BeginInvokeOnMainThread(() => {
  foreach (var characteristic in service.Characteristics) {
- characteristics.Add(characteristic);
+ if (!guidToCharacteristic.ContainsKey(characteristic.ID))
+ {
+ characteristics.Add(characteristic);
+ guidToCharacteristic.Add(characteristic.ID, characteristic);
+ }
  }
  });
  };

Sample Apps/BLE Explorer/Robotics.Mobile.BtLEExplorer.Core/Pages/DeviceList.xaml.cs

@@ -12,17 +12,23 @@ public partial class DeviceList : ContentPage
  { 
  IAdapter adapter;
  ObservableCollection<IDevice> devices;
+ Dictionary<Guid, IDevice> guidToDevices;
 
  public DeviceList (IAdapter adapter)
  {
  InitializeComponent ();
  this.adapter = adapter;
  this.devices = new ObservableCollection<IDevice> ();
+ this.guidToDevices = new Dictionary<Guid, IDevice> ();
  listView.ItemsSource = devices;
 
  adapter.DeviceDiscovered += (object sender, DeviceDiscoveredEventArgs e) => {
  Device.BeginInvokeOnMainThread(() => {
- devices.Add (e.Device);
+ if (!guidToDevices.ContainsKey(e.Device.ID))
+ {
+ devices.Add (e.Device);
+ guidToDevices.Add(e.Device.ID, e.Device);
+ }
  });
  };
 
@@ -66,6 +72,7 @@ void StartScanning (Guid forService) {
  Debug.WriteLine ("adapter.StopScanningForDevices()");
  } else {
  devices.Clear();
+ guidToDevices.Clear ();
  adapter.StartScanningForDevices(forService);
  Debug.WriteLine ("adapter.StartScanningForDevices("+forService+")");
  }

Sample Apps/BLE Explorer/Robotics.Mobile.BtLEExplorer.Core/Pages/ServiceList.xaml.cs

@@ -13,13 +13,15 @@ public partial class ServiceList : ContentPage
  IDevice device;
 
  ObservableCollection<IService> services;
+ Dictionary<Guid, IService> guidToServices;
 
  public ServiceList (IAdapter adapter, IDevice device)
  {
  InitializeComponent ();
  this.adapter = adapter;
  this.device = device;
  this.services = new ObservableCollection<IService> ();
+ this.guidToServices = new Dictionary<Guid, IService> ();
  listView.ItemsSource = services;
 
  // when device is connected
@@ -33,7 +35,11 @@ public ServiceList (IAdapter adapter, IDevice device)
  if (services.Count == 0)
  Device.BeginInvokeOnMainThread(() => {
  foreach (var service in device.Services) {
- services.Add(service);
+ if (!guidToServices.ContainsKey(service.ID))
+ {
+ services.Add(service);
+ guidToServices.Add(service.ID, service);
+ }
  }
  });
  };