From ba6b2899a2251844846261e2291871fc65641cfd Mon Sep 17 00:00:00 2001
From: James Montemagno <james.montemagno@gmail.com>
Date: Tue, 17 Jul 2018 14:16:47 -0700
Subject: [PATCH] Sample Project Tweaks and Optimizations (#353)

* Make sure orientation sensor stops on sample.

* Fix up all sensors page to start and stop correctly

* Only check permission if unknown status

* Update to latest sdk.extras

* fix back button press on TTS page. Check for null.

* Add samples sln for CI/CD

* Update readme and samples sln

* Don't use code sign key for simbuilds

* let's try this gain

* Update to projects

* Cleanup sample config

* bump sdk extras
---
 .../DeviceTests.Android.csproj                |  14 +++
 .../DeviceTests.UWP/DeviceTests.UWP.csproj    |  36 ++++++
 .../DeviceTests.iOS/DeviceTests.iOS.csproj    |  34 +++++
 README.md                                     |  57 +++++----
 .../Samples.Android/Samples.Android.csproj    |  12 ++
 Samples/Samples.UWP/Samples.UWP.csproj        |  36 ++++++
 Samples/Samples.iOS/Samples.iOS.csproj        |  25 +++-
 Samples/Samples/Samples.csproj                |   7 +-
 Samples/Samples/View/AllSensorsPage.xaml      |  12 +-
 Samples/Samples/View/AllSensorsPage.xaml.cs   |  28 ++++-
 Samples/Samples/View/BasePage.cs              |  20 ++-
 .../ViewModel/OrientationSensorViewModel.cs   |   2 +-
 .../ViewModel/TextToSpeechViewModel.cs        |   2 +-
 Tests/Tests.csproj                            |   3 +-
 Xamarin.Essentials.sln                        | 118 ++++++++++++++++++
 .../Permissions/Permissions.ios.cs            |   7 +-
 Xamarin.Essentials/Xamarin.Essentials.csproj  |   8 +-
 17 files changed, 372 insertions(+), 49 deletions(-)

diff --git a/DeviceTests/DeviceTests.Android/DeviceTests.Android.csproj b/DeviceTests/DeviceTests.Android/DeviceTests.Android.csproj
index 71efa7f..07d8b8a 100644
--- a/DeviceTests/DeviceTests.Android/DeviceTests.Android.csproj
+++ b/DeviceTests/DeviceTests.Android/DeviceTests.Android.csproj
@@ -43,6 +43,20 @@
     <JavaMaximumHeapSize>1G</JavaMaximumHeapSize>
     <AndroidLinkSkip />
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Samples|AnyCPU'">
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>pdbonly</DebugType>
+    <Optimize>true</Optimize>
+    <OutputPath>bin\Samples</OutputPath>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+    <AndroidManagedSymbols>true</AndroidManagedSymbols>
+    <AndroidUseSharedRuntime>false</AndroidUseSharedRuntime>
+    <AndroidSupportedAbis>armeabi;armeabi-v7a;x86;x86_64;arm64-v8a</AndroidSupportedAbis>
+    <EmbedAssembliesIntoApk>true</EmbedAssembliesIntoApk>
+    <JavaMaximumHeapSize>1G</JavaMaximumHeapSize>
+    <AndroidLinkSkip />
+  </PropertyGroup>
   <ItemGroup>
     <Reference Include="Mono.Android" />
     <Reference Include="System" />
diff --git a/DeviceTests/DeviceTests.UWP/DeviceTests.UWP.csproj b/DeviceTests/DeviceTests.UWP/DeviceTests.UWP.csproj
index 6090645..792be1b 100644
--- a/DeviceTests/DeviceTests.UWP/DeviceTests.UWP.csproj
+++ b/DeviceTests/DeviceTests.UWP/DeviceTests.UWP.csproj
@@ -89,6 +89,42 @@
     <Prefer32Bit>true</Prefer32Bit>
     <UseDotNetNativeToolchain>true</UseDotNetNativeToolchain>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Samples|ARM'">
+    <OutputPath>bin\ARM\Samples\</OutputPath>
+    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
+    <Optimize>true</Optimize>
+    <NoWarn>;2008;NU1603</NoWarn>
+    <DebugType>pdbonly</DebugType>
+    <PlatformTarget>ARM</PlatformTarget>
+    <UseVSHostingProcess>false</UseVSHostingProcess>
+    <ErrorReport>prompt</ErrorReport>
+    <Prefer32Bit>true</Prefer32Bit>
+    <UseDotNetNativeToolchain>true</UseDotNetNativeToolchain>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Samples|x64'">
+    <OutputPath>bin\x64\Samples\</OutputPath>
+    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
+    <Optimize>true</Optimize>
+    <NoWarn>;2008;NU1603</NoWarn>
+    <DebugType>pdbonly</DebugType>
+    <PlatformTarget>x64</PlatformTarget>
+    <UseVSHostingProcess>false</UseVSHostingProcess>
+    <ErrorReport>prompt</ErrorReport>
+    <Prefer32Bit>true</Prefer32Bit>
+    <UseDotNetNativeToolchain>true</UseDotNetNativeToolchain>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Samples|x86'">
+    <OutputPath>bin\x86\Samples\</OutputPath>
+    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
+    <Optimize>true</Optimize>
+    <NoWarn>;2008;NU1603</NoWarn>
+    <DebugType>pdbonly</DebugType>
+    <PlatformTarget>x86</PlatformTarget>
+    <UseVSHostingProcess>false</UseVSHostingProcess>
+    <ErrorReport>prompt</ErrorReport>
+    <Prefer32Bit>true</Prefer32Bit>
+    <UseDotNetNativeToolchain>true</UseDotNetNativeToolchain>
+  </PropertyGroup>
   <ItemGroup>
     <PackageReference Include="UnitTests.HeadlessRunner" Version="2.0.0" />
     <PackageReference Include="Xamarin.Forms" Version="3.1.0.583944" />
diff --git a/DeviceTests/DeviceTests.iOS/DeviceTests.iOS.csproj b/DeviceTests/DeviceTests.iOS/DeviceTests.iOS.csproj
index fd10680..d23c4b3 100644
--- a/DeviceTests/DeviceTests.iOS/DeviceTests.iOS.csproj
+++ b/DeviceTests/DeviceTests.iOS/DeviceTests.iOS.csproj
@@ -27,6 +27,10 @@
     <CodesignKey>iPhone Developer</CodesignKey>
     <CodesignKey />
     <CodesignEntitlements>Entitlements.plist</CodesignEntitlements>
+    <CodesignProvision>
+    </CodesignProvision>
+    <CodesignExtraArgs />
+    <CodesignResourceRules />
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|iPhoneSimulator' ">
     <DebugSymbols>true</DebugSymbols>
@@ -69,6 +73,36 @@
     <CodesignKey>iPhone Developer</CodesignKey>
     <CodesignEntitlements>Entitlements.plist</CodesignEntitlements>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Samples|iPhoneSimulator'">
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>pdbonly</DebugType>
+    <Optimize>true</Optimize>
+    <OutputPath>bin\iPhoneSimulator\Samples</OutputPath>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+    <MtouchLink>SdkOnly</MtouchLink>
+    <MtouchArch>x86_64</MtouchArch>
+    <ConsolePause>false</ConsolePause>
+    <CodesignKey>iPhone Developer</CodesignKey>
+    <CodesignKey />
+    <CodesignEntitlements>Entitlements.plist</CodesignEntitlements>
+    <MtouchExtraArgs>--linkskip=Xamarin.Forms.Platform.iOS --linkskip=Xamarin.Forms.Platform --linkskip=Xamarin.Forms.Core --linkskip=Xamarin.Forms.Xaml</MtouchExtraArgs>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Samples|iPhone'">
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>pdbonly</DebugType>
+    <Optimize>true</Optimize>
+    <OutputPath>bin\iPhone\Samples</OutputPath>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+    <MtouchArch>ARM64</MtouchArch>
+    <ConsolePause>false</ConsolePause>
+    <CodesignKey>iPhone Developer</CodesignKey>
+    <CodesignEntitlements>Entitlements.plist</CodesignEntitlements>
+  </PropertyGroup>
+  <PropertyGroup Condition=" '$(RunConfiguration)' == 'Default' ">
+    <AppExtensionDebugBundleId />
+  </PropertyGroup>
   <ItemGroup>
     <Reference Include="System" />
     <Reference Include="System.Xml" />
diff --git a/README.md b/README.md
index 858eb30..188b217 100644
--- a/README.md
+++ b/README.md
@@ -13,6 +13,8 @@ iOS, Android, and UWP offer unique operating system and platform APIs that devel
 | Jenkins      | Build        | Windows  | [![Jenkins Build Status](https://jenkins.mono-project.com/buildStatus/icon?job=Components-Essentials)](https://jenkins.mono-project.com/view/Components/job/Components-Essentials/)        |
 | VSTS         | Build        | Windows  | ![VSTS Build Status](https://devdiv.visualstudio.com/_apis/public/build/definitions/0bdbc590-a062-4c3f-b0f6-9383f67865ee/8538/badge)                                                   |
 | Jenkins      | Device Tests | macOS    | [![Build Status](https://jenkins.mono-project.com/buildStatus/icon?job=Components-Essentials-DeviceTests-Mac)](https://jenkins.mono-project.com/job/Components-Essentials-DeviceTests-Mac) |
+| App Center   | Sample App   | Android  | [![Build status](https://build.appcenter.ms/v0.1/apps/7a1f46ca-ba2f-477e-aacc-ff013c7d5f7a/branches/master/badge)](https://appcenter.ms) |
+| App Center   | Sample App   | iOS      | [![Build status](https://build.appcenter.ms/v0.1/apps/43b39e9e-2b2b-482f-8afa-e9906334c85e/branches/master/badge)](https://appcenter.ms) |
 
 ## Installation
 Xamarin.Essentials is available via:
@@ -31,34 +33,35 @@ Xamarin.Essentials is focused on the following platforms:
  - Android (4.4+)
  - UWP (Fall Creators Update+)
 
-## Current APIs:
+## API Documentation:
 The following cross-platform APIs are available in Xamarin.Essentials:
- - [x] [Accelerometer](https://docs.microsoft.com/xamarin/essentials/accelerometer)
- - [X] [App Information](https://docs.microsoft.com/xamarin/essentials/app-information)
- - [x] [Battery](https://docs.microsoft.com/xamarin/essentials/battery)
- - [x] [Clipboard](https://docs.microsoft.com/xamarin/essentials/clipboard)
- - [x] [Compass](https://docs.microsoft.com/xamarin/essentials/compass)
- - [x] [Connectivity](https://docs.microsoft.com/xamarin/essentials/connectivity)
- - [x] [Data Transfer (Share)](https://docs.microsoft.com/xamarin/essentials/data-transfer)
- - [x] [Device Display Information](https://docs.microsoft.com/en-us/xamarin/essentials/device-display)
- - [x] [Device Information](https://docs.microsoft.com/xamarin/essentials/device-information)
- - [x] [Email](https://docs.microsoft.com/xamarin/essentials/email)
- - [x] [File System Helpers](https://docs.microsoft.com/xamarin/essentials/file-system-helpers)
- - [x] [Flashlight](https://docs.microsoft.com/xamarin/essentials/flashlight)
- - [x] [Geocoding](https://docs.microsoft.com/xamarin/essentials/geocoding)
- - [x] [Geolocation](https://docs.microsoft.com/xamarin/essentials/geolocation)
- - [x] [Gyroscope](https://docs.microsoft.com/xamarin/essentials/gyroscope)
- - [x] [Magnetometer](https://docs.microsoft.com/xamarin/essentials/magnetometer)
- - [x] [Open Browser](https://docs.microsoft.com/xamarin/essentials/open-browser)
- - [x] [Orientation Sensor](https://docs.microsoft.com/en-us/xamarin/essentials/orientation-sensor)
- - [x] [Phone Dialer](https://docs.microsoft.com/xamarin/essentials/phone-dialer)
- - [x] [Preferences](https://docs.microsoft.com/xamarin/essentials/preferences)
- - [x] [Screen Lock](https://docs.microsoft.com/xamarin/essentials/screen-lock)
- - [x] [Secure Storage](https://docs.microsoft.com/xamarin/essentials/secure-storage)
- - [x] [SMS](https://docs.microsoft.com/xamarin/essentials/sms)
- - [x] [Text-to-Speech](https://docs.microsoft.com/xamarin/essentials/text-to-speech)
- - [x] [Version Tracking](https://docs.microsoft.com/xamarin/essentials/version-tracking)
- - [x] [Vibrate](https://docs.microsoft.com/xamarin/essentials/vibrate)
+ - [Accelerometer](https://docs.microsoft.com/xamarin/essentials/accelerometer)
+ - [App Information](https://docs.microsoft.com/xamarin/essentials/app-information)
+ - [Battery](https://docs.microsoft.com/xamarin/essentials/battery)
+ - [Clipboard](https://docs.microsoft.com/xamarin/essentials/clipboard)
+ - [Compass](https://docs.microsoft.com/xamarin/essentials/compass)
+ - [Connectivity](https://docs.microsoft.com/xamarin/essentials/connectivity)
+ - [Data Transfer (Share)](https://docs.microsoft.com/xamarin/essentials/data-transfer)
+ - [Device Display Information](https://docs.microsoft.com/en-us/xamarin/essentials/device-display)
+ - [Device Information](https://docs.microsoft.com/xamarin/essentials/device-information)
+ - [Email](https://docs.microsoft.com/xamarin/essentials/email)
+ - [File System Helpers](https://docs.microsoft.com/xamarin/essentials/file-system-helpers)
+ - [Flashlight](https://docs.microsoft.com/xamarin/essentials/flashlight)
+ - [Geocoding](https://docs.microsoft.com/xamarin/essentials/geocoding)
+ - [Geolocation](https://docs.microsoft.com/xamarin/essentials/geolocation)
+ - [Gyroscope](https://docs.microsoft.com/xamarin/essentials/gyroscope)
+ - [Magnetometer](https://docs.microsoft.com/xamarin/essentials/magnetometer)
+ - [Open Browser](https://docs.microsoft.com/xamarin/essentials/open-browser)
+ - [Orientation Sensor](https://docs.microsoft.com/en-us/xamarin/essentials/orientation-sensor)
+ - [Power](https://docs.microsoft.com/en-us/xamarin/essentials/power)
+ - [Phone Dialer](https://docs.microsoft.com/xamarin/essentials/phone-dialer)
+ - [Preferences](https://docs.microsoft.com/xamarin/essentials/preferences)
+ - [Screen Lock](https://docs.microsoft.com/xamarin/essentials/screen-lock)
+ - [Secure Storage](https://docs.microsoft.com/xamarin/essentials/secure-storage)
+ - [SMS](https://docs.microsoft.com/xamarin/essentials/sms)
+ - [Text-to-Speech](https://docs.microsoft.com/xamarin/essentials/text-to-speech)
+ - [Version Tracking](https://docs.microsoft.com/xamarin/essentials/version-tracking)
+ - [Vibrate](https://docs.microsoft.com/xamarin/essentials/vibrate)
  
 ## Contributing
 Please read through our [Contribution Guide](CONTRIBUTING.md). We are not accepting new PRs for full features, however any issue that is marked as `up for grabs` are open for community contributions. We encourage creating new issues for bugs found during usage that the team will triage. Additionally, we are open for code refactoring suggestions in PRs.
diff --git a/Samples/Samples.Android/Samples.Android.csproj b/Samples/Samples.Android/Samples.Android.csproj
index a9dce9e..c3e8598 100644
--- a/Samples/Samples.Android/Samples.Android.csproj
+++ b/Samples/Samples.Android/Samples.Android.csproj
@@ -42,6 +42,18 @@
     <AndroidSupportedAbis />
     <JavaMaximumHeapSize>1G</JavaMaximumHeapSize>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Samples|AnyCPU'">
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>pdbonly</DebugType>
+    <Optimize>true</Optimize>
+    <OutputPath>bin\Samples</OutputPath>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+    <AndroidManagedSymbols>true</AndroidManagedSymbols>
+    <AndroidUseSharedRuntime>false</AndroidUseSharedRuntime>
+    <AndroidSupportedAbis />
+    <JavaMaximumHeapSize>1G</JavaMaximumHeapSize>
+  </PropertyGroup>
   <ItemGroup>
     <Reference Include="Mono.Android" />
     <Reference Include="System" />
diff --git a/Samples/Samples.UWP/Samples.UWP.csproj b/Samples/Samples.UWP/Samples.UWP.csproj
index 5eb3276..def986a 100644
--- a/Samples/Samples.UWP/Samples.UWP.csproj
+++ b/Samples/Samples.UWP/Samples.UWP.csproj
@@ -89,6 +89,42 @@
     <Prefer32Bit>true</Prefer32Bit>
     <UseDotNetNativeToolchain>true</UseDotNetNativeToolchain>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Samples|ARM'">
+    <OutputPath>bin\ARM\Samples\</OutputPath>
+    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
+    <Optimize>true</Optimize>
+    <NoWarn>;2008</NoWarn>
+    <DebugType>pdbonly</DebugType>
+    <PlatformTarget>ARM</PlatformTarget>
+    <UseVSHostingProcess>false</UseVSHostingProcess>
+    <ErrorReport>prompt</ErrorReport>
+    <Prefer32Bit>true</Prefer32Bit>
+    <UseDotNetNativeToolchain>true</UseDotNetNativeToolchain>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Samples|x64'">
+   <OutputPath>bin\x64\Samples\</OutputPath>
+    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
+    <Optimize>true</Optimize>
+    <NoWarn>;2008</NoWarn>
+    <DebugType>pdbonly</DebugType>
+    <PlatformTarget>x64</PlatformTarget>
+    <UseVSHostingProcess>false</UseVSHostingProcess>
+    <ErrorReport>prompt</ErrorReport>
+    <Prefer32Bit>true</Prefer32Bit>
+    <UseDotNetNativeToolchain>true</UseDotNetNativeToolchain>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Samples|x86'">
+   <OutputPath>bin\x86\Samples\</OutputPath>
+    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
+    <Optimize>true</Optimize>
+    <NoWarn>;2008</NoWarn>
+    <DebugType>pdbonly</DebugType>
+    <PlatformTarget>x86</PlatformTarget>
+    <UseVSHostingProcess>false</UseVSHostingProcess>
+    <ErrorReport>prompt</ErrorReport>
+    <Prefer32Bit>true</Prefer32Bit>
+    <UseDotNetNativeToolchain>true</UseDotNetNativeToolchain>
+  </PropertyGroup>
   <ItemGroup>
     <PackageReference Include="Xamarin.Forms" Version="3.1.0.583944" />
     <PackageReference Include="Microsoft.NETCore.UniversalWindowsPlatform" Version="6.1.5" />
diff --git a/Samples/Samples.iOS/Samples.iOS.csproj b/Samples/Samples.iOS/Samples.iOS.csproj
index cdcfd18..26f82e1 100644
--- a/Samples/Samples.iOS/Samples.iOS.csproj
+++ b/Samples/Samples.iOS/Samples.iOS.csproj
@@ -26,8 +26,8 @@
     <MtouchDebug>true</MtouchDebug>
     <MtouchExtraArgs>--linkskip=Xamarin.Forms.Platform.iOS --linkskip=Xamarin.Forms.Platform --linkskip=Xamarin.Forms.Core --linkskip=Xamarin.Forms.Xaml --linkskip=Samples</MtouchExtraArgs>
     <CodesignKey>iPhone Developer</CodesignKey>
-    <CodesignKey />
     <CodesignEntitlements>Entitlements.plist</CodesignEntitlements>
+    <CodesignProvision />
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|iPhoneSimulator' ">
     <DebugSymbols>true</DebugSymbols>
@@ -68,6 +68,29 @@
     <CodesignKey>iPhone Developer</CodesignKey>
     <CodesignEntitlements>Entitlements.plist</CodesignEntitlements>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Samples|iPhoneSimulator'">
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>pdbonly</DebugType>
+    <Optimize>true</Optimize>
+    <OutputPath>bin\iPhoneSimulator\Samples</OutputPath>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+    <MtouchLink>None</MtouchLink>
+    <MtouchArch>x86_64</MtouchArch>
+    <ConsolePause>false</ConsolePause>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Samples|iPhone'">
+    <DebugSymbols>true</DebugSymbols>
+    <DebugType>pdbonly</DebugType>
+    <Optimize>true</Optimize>
+    <OutputPath>bin\iPhone\Samples</OutputPath>
+    <ErrorReport>prompt</ErrorReport>
+    <WarningLevel>4</WarningLevel>
+    <MtouchArch>ARM64</MtouchArch>
+    <ConsolePause>false</ConsolePause>
+    <CodesignKey>iPhone Developer</CodesignKey>
+    <CodesignEntitlements>Entitlements.plist</CodesignEntitlements>
+  </PropertyGroup>
   <ItemGroup>
     <Reference Include="System" />
     <Reference Include="System.Xml" />
diff --git a/Samples/Samples/Samples.csproj b/Samples/Samples/Samples.csproj
index 121bb84..720c7a3 100644
--- a/Samples/Samples/Samples.csproj
+++ b/Samples/Samples/Samples.csproj
@@ -1,7 +1,8 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
+    <Configurations>Debug;Release;Samples</Configurations>
   </PropertyGroup>
 
   <PropertyGroup Condition=" '$(Configuration)'=='Debug' ">
@@ -12,6 +13,10 @@
     <DebugType>pdbonly</DebugType>
     <DebugSymbols>true</DebugSymbols>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)'=='Samples'">
+    <DebugType>pdbonly</DebugType>
+    <DebugSymbols>true</DebugSymbols>
+  </PropertyGroup>
 
   <ItemGroup>
     <PackageReference Include="Xamarin.Forms" Version="3.1.0.583944" />
diff --git a/Samples/Samples/View/AllSensorsPage.xaml b/Samples/Samples/View/AllSensorsPage.xaml
index 5064198..c2444f6 100644
--- a/Samples/Samples/View/AllSensorsPage.xaml
+++ b/Samples/Samples/View/AllSensorsPage.xaml
@@ -1,7 +1,7 @@
 <views:BasePage xmlns="http://xamarin.com/schemas/2014/forms"
              xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
-             xmlns:views="clr-namespace:Samples.View"
              xmlns:viewmodels="clr-namespace:Samples.ViewModel"
+             xmlns:views="clr-namespace:Samples.View"
              x:Class="Samples.View.AllSensorsPage"
              Title="All Sensors">
 
@@ -12,7 +12,7 @@
             <StackLayout Padding="12,0,12,12" Spacing="6">
 
                 <Label Text="Accelerometer" FontAttributes="Bold" Margin="0,6,0,0" />
-                <Grid>
+                <Grid x:Name="GridAccelerometer">
                     <Grid.BindingContext>
                         <viewmodels:AccelerometerViewModel />
                     </Grid.BindingContext>
@@ -46,7 +46,7 @@
                 </Grid>
 
                 <Label Text="Compass" FontAttributes="Bold" Margin="0,6,0,0" />
-                <Grid>
+                <Grid x:Name="GridCompass">
                     <Grid.BindingContext>
                         <viewmodels:CompassViewModel />
                     </Grid.BindingContext>
@@ -75,7 +75,7 @@
                 </Grid>
 
                 <Label Text="Gyroscope" FontAttributes="Bold" Margin="0,6,0,0" />
-                <Grid>
+                <Grid x:Name="GridGyro">
                     <Grid.BindingContext>
                         <viewmodels:GyroscopeViewModel />
                     </Grid.BindingContext>
@@ -109,7 +109,7 @@
                 </Grid>
 
                 <Label Text="Magnetometer" FontAttributes="Bold" Margin="0,6,0,0" />
-                <Grid>
+                <Grid x:Name="GridMagnetometer">
                     <Grid.BindingContext>
                         <viewmodels:MagnetometerViewModel />
                     </Grid.BindingContext>
@@ -143,7 +143,7 @@
                 </Grid>
                 
                 <Label Text="Orientation Sensor" FontAttributes="Bold" Margin="0,6,0,0" />
-                <Grid>
+                <Grid x:Name="GridOrientation">
                     <Grid.BindingContext>
                         <viewmodels:OrientationSensorViewModel />
                     </Grid.BindingContext>
diff --git a/Samples/Samples/View/AllSensorsPage.xaml.cs b/Samples/Samples/View/AllSensorsPage.xaml.cs
index 3846ebc..882e1cf 100644
--- a/Samples/Samples/View/AllSensorsPage.xaml.cs
+++ b/Samples/Samples/View/AllSensorsPage.xaml.cs
@@ -1,4 +1,8 @@
-namespace Samples.View
+using System.Threading.Tasks;
+using Samples.ViewModel;
+using Xamarin.Forms;
+
+namespace Samples.View
 {
     public partial class AllSensorsPage : BasePage
     {
@@ -6,5 +10,27 @@
         {
             InitializeComponent();
         }
+
+        protected override void OnAppearing()
+        {
+            base.OnAppearing();
+
+            SetupBinding(GridAccelerometer.BindingContext);
+            SetupBinding(GridCompass.BindingContext);
+            SetupBinding(GridGyro.BindingContext);
+            SetupBinding(GridMagnetometer.BindingContext);
+            SetupBinding(GridOrientation.BindingContext);
+        }
+
+        protected override void OnDisappearing()
+        {
+            TearDownBinding(GridAccelerometer.BindingContext);
+            TearDownBinding(GridCompass.BindingContext);
+            TearDownBinding(GridGyro.BindingContext);
+            TearDownBinding(GridMagnetometer.BindingContext);
+            TearDownBinding(GridOrientation.BindingContext);
+
+            base.OnDisappearing();
+        }
     }
 }
diff --git a/Samples/Samples/View/BasePage.cs b/Samples/Samples/View/BasePage.cs
index 2362e28..49e1f41 100644
--- a/Samples/Samples/View/BasePage.cs
+++ b/Samples/Samples/View/BasePage.cs
@@ -15,22 +15,32 @@ namespace Samples.View
         {
             base.OnAppearing();
 
-            if (BindingContext is BaseViewModel vm)
+            SetupBinding(BindingContext);
+        }
+
+        protected override void OnDisappearing()
+        {
+            TearDownBinding(BindingContext);
+
+            base.OnDisappearing();
+        }
+
+        protected void SetupBinding(object bindingContext)
+        {
+            if (bindingContext is BaseViewModel vm)
             {
                 vm.DoDisplayAlert += OnDisplayAlert;
                 vm.OnAppearing();
             }
         }
 
-        protected override void OnDisappearing()
+        protected void TearDownBinding(object bindingContext)
         {
-            if (BindingContext is BaseViewModel vm)
+            if (bindingContext is BaseViewModel vm)
             {
                 vm.OnDisappearing();
                 vm.DoDisplayAlert -= OnDisplayAlert;
             }
-
-            base.OnDisappearing();
         }
 
         Task OnDisplayAlert(string message)
diff --git a/Samples/Samples/ViewModel/OrientationSensorViewModel.cs b/Samples/Samples/ViewModel/OrientationSensorViewModel.cs
index 3ec9e8e..29f91f0 100644
--- a/Samples/Samples/ViewModel/OrientationSensorViewModel.cs
+++ b/Samples/Samples/ViewModel/OrientationSensorViewModel.cs
@@ -100,7 +100,7 @@ namespace Samples.ViewModel
         void OnStop()
         {
             IsActive = false;
-            Accelerometer.Stop();
+            OrientationSensor.Stop();
         }
 
         void OnReadingChanged(OrientationSensorChangedEventArgs e)
diff --git a/Samples/Samples/ViewModel/TextToSpeechViewModel.cs b/Samples/Samples/ViewModel/TextToSpeechViewModel.cs
index 89cc3dd..13a3227 100644
--- a/Samples/Samples/ViewModel/TextToSpeechViewModel.cs
+++ b/Samples/Samples/ViewModel/TextToSpeechViewModel.cs
@@ -77,7 +77,7 @@ namespace Samples.ViewModel
 
         void OnCancel()
         {
-            if (!IsBusy && !cts.IsCancellationRequested)
+            if (!IsBusy && (cts == null || !cts.IsCancellationRequested))
                 return;
 
             cts.Cancel();
diff --git a/Tests/Tests.csproj b/Tests/Tests.csproj
index 1a2c5f8..f7ff1e7 100644
--- a/Tests/Tests.csproj
+++ b/Tests/Tests.csproj
@@ -3,10 +3,11 @@
   <PropertyGroup>
     <TargetFramework>netcoreapp2.0</TargetFramework>
     <IsPackable>false</IsPackable>
+    <Configurations>Debug;Release;Samples</Configurations>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.5.0" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.7.2" />
     <PackageReference Include="xunit" Version="2.3.1" />
     <PackageReference Include="xunit.runner.visualstudio" Version="2.3.1" />
     <DotNetCliToolReference Include="dotnet-xunit" Version="2.3.1" />
diff --git a/Xamarin.Essentials.sln b/Xamarin.Essentials.sln
index 24ddd0b..5179e0e 100644
--- a/Xamarin.Essentials.sln
+++ b/Xamarin.Essentials.sln
@@ -59,6 +59,12 @@ Global
 		Release|iPhoneSimulator = Release|iPhoneSimulator
 		Release|x64 = Release|x64
 		Release|x86 = Release|x86
+		Samples|Any CPU = Samples|Any CPU
+		Samples|ARM = Samples|ARM
+		Samples|iPhone = Samples|iPhone
+		Samples|iPhoneSimulator = Samples|iPhoneSimulator
+		Samples|x64 = Samples|x64
+		Samples|x86 = Samples|x86
 	EndGlobalSection
 	GlobalSection(ProjectConfigurationPlatforms) = postSolution
 		{63A4F6A1-48BF-4D32-AED7-82F605EDB042}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
@@ -85,6 +91,18 @@ Global
 		{63A4F6A1-48BF-4D32-AED7-82F605EDB042}.Release|x64.Build.0 = Release|Any CPU
 		{63A4F6A1-48BF-4D32-AED7-82F605EDB042}.Release|x86.ActiveCfg = Release|Any CPU
 		{63A4F6A1-48BF-4D32-AED7-82F605EDB042}.Release|x86.Build.0 = Release|Any CPU
+		{63A4F6A1-48BF-4D32-AED7-82F605EDB042}.Samples|Any CPU.ActiveCfg = Samples|Any CPU
+		{63A4F6A1-48BF-4D32-AED7-82F605EDB042}.Samples|Any CPU.Build.0 = Samples|Any CPU
+		{63A4F6A1-48BF-4D32-AED7-82F605EDB042}.Samples|ARM.ActiveCfg = Samples|Any CPU
+		{63A4F6A1-48BF-4D32-AED7-82F605EDB042}.Samples|ARM.Build.0 = Samples|Any CPU
+		{63A4F6A1-48BF-4D32-AED7-82F605EDB042}.Samples|iPhone.ActiveCfg = Samples|Any CPU
+		{63A4F6A1-48BF-4D32-AED7-82F605EDB042}.Samples|iPhone.Build.0 = Samples|Any CPU
+		{63A4F6A1-48BF-4D32-AED7-82F605EDB042}.Samples|iPhoneSimulator.ActiveCfg = Samples|Any CPU
+		{63A4F6A1-48BF-4D32-AED7-82F605EDB042}.Samples|iPhoneSimulator.Build.0 = Samples|Any CPU
+		{63A4F6A1-48BF-4D32-AED7-82F605EDB042}.Samples|x64.ActiveCfg = Samples|Any CPU
+		{63A4F6A1-48BF-4D32-AED7-82F605EDB042}.Samples|x64.Build.0 = Samples|Any CPU
+		{63A4F6A1-48BF-4D32-AED7-82F605EDB042}.Samples|x86.ActiveCfg = Samples|Any CPU
+		{63A4F6A1-48BF-4D32-AED7-82F605EDB042}.Samples|x86.Build.0 = Samples|Any CPU
 		{77C2F93D-6EB7-49F7-A74A-C80499EC206A}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
 		{77C2F93D-6EB7-49F7-A74A-C80499EC206A}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{77C2F93D-6EB7-49F7-A74A-C80499EC206A}.Debug|ARM.ActiveCfg = Debug|Any CPU
@@ -109,6 +127,17 @@ Global
 		{77C2F93D-6EB7-49F7-A74A-C80499EC206A}.Release|x64.Build.0 = Release|Any CPU
 		{77C2F93D-6EB7-49F7-A74A-C80499EC206A}.Release|x86.ActiveCfg = Release|Any CPU
 		{77C2F93D-6EB7-49F7-A74A-C80499EC206A}.Release|x86.Build.0 = Release|Any CPU
+		{77C2F93D-6EB7-49F7-A74A-C80499EC206A}.Samples|Any CPU.ActiveCfg = Samples|Any CPU
+		{77C2F93D-6EB7-49F7-A74A-C80499EC206A}.Samples|ARM.ActiveCfg = Samples|Any CPU
+		{77C2F93D-6EB7-49F7-A74A-C80499EC206A}.Samples|ARM.Build.0 = Samples|Any CPU
+		{77C2F93D-6EB7-49F7-A74A-C80499EC206A}.Samples|iPhone.ActiveCfg = Samples|Any CPU
+		{77C2F93D-6EB7-49F7-A74A-C80499EC206A}.Samples|iPhone.Build.0 = Samples|Any CPU
+		{77C2F93D-6EB7-49F7-A74A-C80499EC206A}.Samples|iPhoneSimulator.ActiveCfg = Samples|Any CPU
+		{77C2F93D-6EB7-49F7-A74A-C80499EC206A}.Samples|iPhoneSimulator.Build.0 = Samples|Any CPU
+		{77C2F93D-6EB7-49F7-A74A-C80499EC206A}.Samples|x64.ActiveCfg = Samples|Any CPU
+		{77C2F93D-6EB7-49F7-A74A-C80499EC206A}.Samples|x64.Build.0 = Samples|Any CPU
+		{77C2F93D-6EB7-49F7-A74A-C80499EC206A}.Samples|x86.ActiveCfg = Samples|Any CPU
+		{77C2F93D-6EB7-49F7-A74A-C80499EC206A}.Samples|x86.Build.0 = Samples|Any CPU
 		{2550ED91-8AE1-4E9A-A964-C11515C8FA28}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
 		{2550ED91-8AE1-4E9A-A964-C11515C8FA28}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{2550ED91-8AE1-4E9A-A964-C11515C8FA28}.Debug|ARM.ActiveCfg = Debug|Any CPU
@@ -133,6 +162,18 @@ Global
 		{2550ED91-8AE1-4E9A-A964-C11515C8FA28}.Release|x64.Build.0 = Release|Any CPU
 		{2550ED91-8AE1-4E9A-A964-C11515C8FA28}.Release|x86.ActiveCfg = Release|Any CPU
 		{2550ED91-8AE1-4E9A-A964-C11515C8FA28}.Release|x86.Build.0 = Release|Any CPU
+		{2550ED91-8AE1-4E9A-A964-C11515C8FA28}.Samples|Any CPU.ActiveCfg = Samples|Any CPU
+		{2550ED91-8AE1-4E9A-A964-C11515C8FA28}.Samples|Any CPU.Build.0 = Samples|Any CPU
+		{2550ED91-8AE1-4E9A-A964-C11515C8FA28}.Samples|ARM.ActiveCfg = Samples|Any CPU
+		{2550ED91-8AE1-4E9A-A964-C11515C8FA28}.Samples|ARM.Build.0 = Samples|Any CPU
+		{2550ED91-8AE1-4E9A-A964-C11515C8FA28}.Samples|iPhone.ActiveCfg = Samples|Any CPU
+		{2550ED91-8AE1-4E9A-A964-C11515C8FA28}.Samples|iPhone.Build.0 = Samples|Any CPU
+		{2550ED91-8AE1-4E9A-A964-C11515C8FA28}.Samples|iPhoneSimulator.ActiveCfg = Samples|Any CPU
+		{2550ED91-8AE1-4E9A-A964-C11515C8FA28}.Samples|iPhoneSimulator.Build.0 = Samples|Any CPU
+		{2550ED91-8AE1-4E9A-A964-C11515C8FA28}.Samples|x64.ActiveCfg = Samples|Any CPU
+		{2550ED91-8AE1-4E9A-A964-C11515C8FA28}.Samples|x64.Build.0 = Samples|Any CPU
+		{2550ED91-8AE1-4E9A-A964-C11515C8FA28}.Samples|x86.ActiveCfg = Samples|Any CPU
+		{2550ED91-8AE1-4E9A-A964-C11515C8FA28}.Samples|x86.Build.0 = Samples|Any CPU
 		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
 		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Debug|Any CPU.Deploy.0 = Debug|Any CPU
@@ -169,6 +210,24 @@ Global
 		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Release|x86.ActiveCfg = Release|Any CPU
 		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Release|x86.Build.0 = Release|Any CPU
 		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Release|x86.Deploy.0 = Release|Any CPU
+		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Samples|Any CPU.ActiveCfg = Samples|Any CPU
+		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Samples|Any CPU.Build.0 = Samples|Any CPU
+		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Samples|Any CPU.Deploy.0 = Samples|Any CPU
+		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Samples|ARM.ActiveCfg = Samples|Any CPU
+		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Samples|ARM.Build.0 = Samples|Any CPU
+		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Samples|ARM.Deploy.0 = Samples|Any CPU
+		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Samples|iPhone.ActiveCfg = Samples|Any CPU
+		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Samples|iPhone.Build.0 = Samples|Any CPU
+		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Samples|iPhone.Deploy.0 = Samples|Any CPU
+		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Samples|iPhoneSimulator.ActiveCfg = Samples|Any CPU
+		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Samples|iPhoneSimulator.Build.0 = Samples|Any CPU
+		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Samples|iPhoneSimulator.Deploy.0 = Samples|Any CPU
+		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Samples|x64.ActiveCfg = Samples|Any CPU
+		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Samples|x64.Build.0 = Samples|Any CPU
+		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Samples|x64.Deploy.0 = Samples|Any CPU
+		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Samples|x86.ActiveCfg = Samples|Any CPU
+		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Samples|x86.Build.0 = Samples|Any CPU
+		{C1CD30D3-52CA-4F8E-8499-BE88567CA2F8}.Samples|x86.Deploy.0 = Samples|Any CPU
 		{E2571C97-C048-4F91-8BB3-546CF7410C4C}.Debug|Any CPU.ActiveCfg = Debug|iPhoneSimulator
 		{E2571C97-C048-4F91-8BB3-546CF7410C4C}.Debug|Any CPU.Build.0 = Debug|iPhoneSimulator
 		{E2571C97-C048-4F91-8BB3-546CF7410C4C}.Debug|ARM.ActiveCfg = Debug|iPhone
@@ -193,6 +252,15 @@ Global
 		{E2571C97-C048-4F91-8BB3-546CF7410C4C}.Release|x64.Build.0 = Release|iPhoneSimulator
 		{E2571C97-C048-4F91-8BB3-546CF7410C4C}.Release|x86.ActiveCfg = Release|iPhoneSimulator
 		{E2571C97-C048-4F91-8BB3-546CF7410C4C}.Release|x86.Build.0 = Release|iPhoneSimulator
+		{E2571C97-C048-4F91-8BB3-546CF7410C4C}.Samples|Any CPU.ActiveCfg = Samples|iPhone
+		{E2571C97-C048-4F91-8BB3-546CF7410C4C}.Samples|Any CPU.Build.0 = Samples|iPhone
+		{E2571C97-C048-4F91-8BB3-546CF7410C4C}.Samples|ARM.ActiveCfg = Samples|iPhone
+		{E2571C97-C048-4F91-8BB3-546CF7410C4C}.Samples|iPhone.ActiveCfg = Samples|iPhone
+		{E2571C97-C048-4F91-8BB3-546CF7410C4C}.Samples|iPhone.Build.0 = Samples|iPhone
+		{E2571C97-C048-4F91-8BB3-546CF7410C4C}.Samples|iPhoneSimulator.ActiveCfg = Samples|iPhoneSimulator
+		{E2571C97-C048-4F91-8BB3-546CF7410C4C}.Samples|iPhoneSimulator.Build.0 = Samples|iPhoneSimulator
+		{E2571C97-C048-4F91-8BB3-546CF7410C4C}.Samples|x64.ActiveCfg = Samples|iPhone
+		{E2571C97-C048-4F91-8BB3-546CF7410C4C}.Samples|x86.ActiveCfg = Samples|iPhone
 		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Debug|Any CPU.ActiveCfg = Debug|x86
 		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Debug|Any CPU.Build.0 = Debug|x86
 		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Debug|Any CPU.Deploy.0 = Debug|x86
@@ -229,6 +297,20 @@ Global
 		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Release|x86.ActiveCfg = Release|x86
 		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Release|x86.Build.0 = Release|x86
 		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Release|x86.Deploy.0 = Release|x86
+		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Samples|Any CPU.ActiveCfg = Samples|x86
+		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Samples|Any CPU.Build.0 = Samples|x86
+		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Samples|Any CPU.Deploy.0 = Samples|x86
+		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Samples|ARM.ActiveCfg = Samples|ARM
+		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Samples|ARM.Build.0 = Samples|ARM
+		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Samples|ARM.Deploy.0 = Samples|ARM
+		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Samples|iPhone.ActiveCfg = Samples|x86
+		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Samples|iPhoneSimulator.ActiveCfg = Samples|x86
+		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Samples|x64.ActiveCfg = Samples|x64
+		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Samples|x64.Build.0 = Samples|x64
+		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Samples|x64.Deploy.0 = Samples|x64
+		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Samples|x86.ActiveCfg = Samples|x86
+		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Samples|x86.Build.0 = Samples|x86
+		{A0798FC9-AB9D-4CCA-AF44-71B7A4691D5A}.Samples|x86.Deploy.0 = Samples|x86
 		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
 		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Debug|Any CPU.Deploy.0 = Debug|Any CPU
@@ -265,6 +347,22 @@ Global
 		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Release|x86.ActiveCfg = Release|Any CPU
 		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Release|x86.Build.0 = Release|Any CPU
 		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Release|x86.Deploy.0 = Release|Any CPU
+		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Samples|Any CPU.ActiveCfg = Samples|Any CPU
+		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Samples|ARM.ActiveCfg = Samples|Any CPU
+		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Samples|ARM.Build.0 = Samples|Any CPU
+		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Samples|ARM.Deploy.0 = Samples|Any CPU
+		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Samples|iPhone.ActiveCfg = Samples|Any CPU
+		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Samples|iPhone.Build.0 = Samples|Any CPU
+		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Samples|iPhone.Deploy.0 = Samples|Any CPU
+		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Samples|iPhoneSimulator.ActiveCfg = Samples|Any CPU
+		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Samples|iPhoneSimulator.Build.0 = Samples|Any CPU
+		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Samples|iPhoneSimulator.Deploy.0 = Samples|Any CPU
+		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Samples|x64.ActiveCfg = Samples|Any CPU
+		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Samples|x64.Build.0 = Samples|Any CPU
+		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Samples|x64.Deploy.0 = Samples|Any CPU
+		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Samples|x86.ActiveCfg = Samples|Any CPU
+		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Samples|x86.Build.0 = Samples|Any CPU
+		{CB2072E0-A437-4811-AE17-16CAE0DDA1B1}.Samples|x86.Deploy.0 = Samples|Any CPU
 		{EE8FC716-27FC-405B-BD27-AF17E01A6671}.Debug|Any CPU.ActiveCfg = Debug|iPhoneSimulator
 		{EE8FC716-27FC-405B-BD27-AF17E01A6671}.Debug|Any CPU.Build.0 = Debug|iPhoneSimulator
 		{EE8FC716-27FC-405B-BD27-AF17E01A6671}.Debug|ARM.ActiveCfg = Debug|iPhone
@@ -289,6 +387,14 @@ Global
 		{EE8FC716-27FC-405B-BD27-AF17E01A6671}.Release|x64.Build.0 = Release|iPhoneSimulator
 		{EE8FC716-27FC-405B-BD27-AF17E01A6671}.Release|x86.ActiveCfg = Release|iPhoneSimulator
 		{EE8FC716-27FC-405B-BD27-AF17E01A6671}.Release|x86.Build.0 = Release|iPhoneSimulator
+		{EE8FC716-27FC-405B-BD27-AF17E01A6671}.Samples|Any CPU.ActiveCfg = Samples|iPhone
+		{EE8FC716-27FC-405B-BD27-AF17E01A6671}.Samples|ARM.ActiveCfg = Samples|iPhone
+		{EE8FC716-27FC-405B-BD27-AF17E01A6671}.Samples|iPhone.ActiveCfg = Samples|iPhone
+		{EE8FC716-27FC-405B-BD27-AF17E01A6671}.Samples|iPhone.Build.0 = Samples|iPhone
+		{EE8FC716-27FC-405B-BD27-AF17E01A6671}.Samples|iPhoneSimulator.ActiveCfg = Samples|iPhoneSimulator
+		{EE8FC716-27FC-405B-BD27-AF17E01A6671}.Samples|iPhoneSimulator.Build.0 = Samples|iPhoneSimulator
+		{EE8FC716-27FC-405B-BD27-AF17E01A6671}.Samples|x64.ActiveCfg = Samples|iPhone
+		{EE8FC716-27FC-405B-BD27-AF17E01A6671}.Samples|x86.ActiveCfg = Samples|iPhone
 		{4BD0D88F-7E7A-4C3B-9E34-BF3717A8FF4B}.Debug|Any CPU.ActiveCfg = Debug|x86
 		{4BD0D88F-7E7A-4C3B-9E34-BF3717A8FF4B}.Debug|Any CPU.Build.0 = Debug|x86
 		{4BD0D88F-7E7A-4C3B-9E34-BF3717A8FF4B}.Debug|Any CPU.Deploy.0 = Debug|x86
@@ -325,6 +431,18 @@ Global
 		{4BD0D88F-7E7A-4C3B-9E34-BF3717A8FF4B}.Release|x86.ActiveCfg = Release|x86
 		{4BD0D88F-7E7A-4C3B-9E34-BF3717A8FF4B}.Release|x86.Build.0 = Release|x86
 		{4BD0D88F-7E7A-4C3B-9E34-BF3717A8FF4B}.Release|x86.Deploy.0 = Release|x86
+		{4BD0D88F-7E7A-4C3B-9E34-BF3717A8FF4B}.Samples|Any CPU.ActiveCfg = Samples|x86
+		{4BD0D88F-7E7A-4C3B-9E34-BF3717A8FF4B}.Samples|ARM.ActiveCfg = Samples|ARM
+		{4BD0D88F-7E7A-4C3B-9E34-BF3717A8FF4B}.Samples|ARM.Build.0 = Samples|ARM
+		{4BD0D88F-7E7A-4C3B-9E34-BF3717A8FF4B}.Samples|ARM.Deploy.0 = Samples|ARM
+		{4BD0D88F-7E7A-4C3B-9E34-BF3717A8FF4B}.Samples|iPhone.ActiveCfg = Samples|x86
+		{4BD0D88F-7E7A-4C3B-9E34-BF3717A8FF4B}.Samples|iPhoneSimulator.ActiveCfg = Samples|x86
+		{4BD0D88F-7E7A-4C3B-9E34-BF3717A8FF4B}.Samples|x64.ActiveCfg = Samples|x64
+		{4BD0D88F-7E7A-4C3B-9E34-BF3717A8FF4B}.Samples|x64.Build.0 = Samples|x64
+		{4BD0D88F-7E7A-4C3B-9E34-BF3717A8FF4B}.Samples|x64.Deploy.0 = Samples|x64
+		{4BD0D88F-7E7A-4C3B-9E34-BF3717A8FF4B}.Samples|x86.ActiveCfg = Samples|x86
+		{4BD0D88F-7E7A-4C3B-9E34-BF3717A8FF4B}.Samples|x86.Build.0 = Samples|x86
+		{4BD0D88F-7E7A-4C3B-9E34-BF3717A8FF4B}.Samples|x86.Deploy.0 = Samples|x86
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
diff --git a/Xamarin.Essentials/Permissions/Permissions.ios.cs b/Xamarin.Essentials/Permissions/Permissions.ios.cs
index 1b97255..408660b 100644
--- a/Xamarin.Essentials/Permissions/Permissions.ios.cs
+++ b/Xamarin.Essentials/Permissions/Permissions.ios.cs
@@ -32,9 +32,10 @@ namespace Xamarin.Essentials
 
         static async Task<PermissionStatus> PlatformRequestAsync(PermissionType permission)
         {
-            // Check status before requesting first
-            if (await PlatformCheckStatusAsync(permission) == PermissionStatus.Granted)
-                return PermissionStatus.Granted;
+            // Check status before requesting first and only request if Unknown
+            var status = await PlatformCheckStatusAsync(permission);
+            if (status != PermissionStatus.Unknown)
+                return status;
 
             EnsureDeclared(permission);
 
diff --git a/Xamarin.Essentials/Xamarin.Essentials.csproj b/Xamarin.Essentials/Xamarin.Essentials.csproj
index 4b2dba1..af7ba34 100644
--- a/Xamarin.Essentials/Xamarin.Essentials.csproj
+++ b/Xamarin.Essentials/Xamarin.Essentials.csproj
@@ -31,6 +31,7 @@
     <PackageRequireLicenseAcceptance>true</PackageRequireLicenseAcceptance>
     <PackageProjectUrl>https://go.microsoft.com/fwlink/?linkid=868960</PackageProjectUrl>
     <MDocDocumentationDirectory>$(MSBuildThisFileDirectory)..\docs\en</MDocDocumentationDirectory>
+    <Configurations>Debug;Release;Samples</Configurations>
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)'=='Debug' ">
     <DebugType>full</DebugType>
@@ -39,9 +40,12 @@
   <PropertyGroup Condition=" '$(Configuration)'=='Release' ">
     <DebugType>pdbonly</DebugType>
   </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)'=='Samples'">
+    <DebugType>pdbonly</DebugType>
+  </PropertyGroup>
   <ItemGroup>
-    <PackageReference Include="mdoc" Version="5.7.0.1" PrivateAssets="All" />
-    <PackageReference Include="MSBuild.Sdk.Extras" Version="1.4.0" PrivateAssets="All" />
+    <PackageReference Include="mdoc" Version="5.7.1" PrivateAssets="All" />
+    <PackageReference Include="MSBuild.Sdk.Extras" Version="1.6.37-preview" PrivateAssets="All" />
     <PackageReference Include="System.Numerics.Vectors" Version="4.5.0" />
     <Compile Include="**\*.shared.cs" />
     <Compile Include="**\*.shared.*.cs" />