Fix for Xamarin.Forms Android issue #10

samples/DO.Samples.Forms/DO.Samples.Forms/DO.Samples.Forms.Android/MainActivity.cs

@@ -20,21 +20,18 @@ protected override void OnCreate(Bundle bundle)
             // Step 1:
             CrossCurrentActivity.Current.Activity = this;
 
-            // Step 2:
-            DeviceOrientationImplementation.Init();
-
             // ...
 
             global::Xamarin.Forms.Forms.Init(this, bundle);
             LoadApplication(new App());
         }
 
-        // Step 3:
+        // Step 2:
         public override void OnConfigurationChanged(Configuration newConfig)
         {
             base.OnConfigurationChanged(newConfig);
 
-            DeviceOrientationImplementation.NotifyOrientationChange(newConfig);
+            DeviceOrientationImplementation.NotifyOrientationChange(newConfig.Orientation);
         }
     }
 }

samples/DO.Samples.Forms/DO.Samples.Forms/DO.Samples.Forms/MainPage.xaml

@@ -4,8 +4,10 @@
              xmlns:local="clr-namespace:DO.Samples.Forms"
              x:Class="DO.Samples.Forms.MainPage">
 
-	<Label Text="Welcome to Xamarin.Forms!" 
-           VerticalOptions="Center" 
-           HorizontalOptions="Center" />
+    <Button x:Name="btn"
+            Text="---------" 
+            VerticalOptions="Center" 
+            HorizontalOptions="Center"
+            Clicked="Button_Click" />
 
 </ContentPage>

samples/DO.Samples.Forms/DO.Samples.Forms/DO.Samples.Forms/MainPage.xaml.cs

@@ -3,17 +3,38 @@
 using System.Linq;
 using System.Text;
 using System.Threading.Tasks;
+using Plugin.DeviceOrientation;
+using Plugin.DeviceOrientation.Abstractions;
 using Xamarin.Forms;
 
 namespace DO.Samples.Forms
 {
-	public partial class MainPage : ContentPage
-	{
-		public MainPage()
-		{
-			InitializeComponent();
+    public partial class MainPage : ContentPage
+    {
+        private bool _isLocked = false;
+
+        public MainPage()
+        {
+            InitializeComponent();
 
             var a = new DSImage(1, 2, 3, 4);
-		}
-	}
+
+            CrossDeviceOrientation.Current.OrientationChanged += CurrentOnOrientationChanged;
+        }
+
+        private void CurrentOnOrientationChanged(object sender, OrientationChangedEventArgs orientationChangedEventArgs)
+        {
+            btn.Text = orientationChangedEventArgs.Orientation.ToString();
+        }
+
+        public void Button_Click(object sender, EventArgs args)
+        {
+            if (_isLocked)
+                CrossDeviceOrientation.Current.LockOrientation(CrossDeviceOrientation.Current.CurrentOrientation);
+            else
+                CrossDeviceOrientation.Current.UnlockOrientation();
+
+            _isLocked = !_isLocked;
+        }
+    }
 }

src/DeviceOrientation/Plugin.DeviceOrientation.Android/DeviceOrientationImplementation.cs

@@ -2,6 +2,7 @@
 using Android.App;
 using Android.Content;
 using Android.Content.PM;
+using Android.Content.Res;
 using Android.Hardware;
 using Android.Runtime;
 using Android.Views;
@@ -14,12 +15,37 @@ public class DeviceOrientationImplementation : BaseDeviceOrientationImplementati
     {
         private readonly OrientationListener _listener;
         private bool _disposed;
+        private bool _isListenerEnabled = true;
+
+        protected bool IsListenerEnabled
+        {
+            set
+            {
+                if (_listener == null) return;
+
+                if (value == _isListenerEnabled) return;
+
+                if (value)
+                {
+                    _listener.Enable();
+                }
+                else
+                {
+                    _listener.Disable();
+                }
+
+                _isListenerEnabled = value;
+            }
+        }
 
         public DeviceOrientationImplementation()
         {
             _listener = new OrientationListener(OnOrientationChanged);
+
             if (_listener.CanDetectOrientation())
+            {
                 _listener.Enable();
+            }
         }
 
         public override DeviceOrientations CurrentOrientation
@@ -63,6 +89,21 @@ public override void Dispose(bool disposing)
             base.Dispose(disposing);
         }
 
+        public static void NotifyOrientationChange(Orientation newOrientation, bool isForms = true)
+        {
+            var instance = (DeviceOrientationImplementation)CrossDeviceOrientation.Current;
+
+            if (instance == null)
+                throw new InvalidCastException("Cast from IDeviceOrientation to Android.DeviceOrientationImplementation");
+
+            instance.IsListenerEnabled = !isForms;
+
+            instance.OnOrientationChanged(new OrientationChangedEventArgs
+            {
+                Orientation = CrossDeviceOrientation.Current.CurrentOrientation
+            });
+        }
+
         private ScreenOrientation Convert(DeviceOrientations orientation)
         {
             switch (orientation)