From 48e052294ea9dc7203a03befb5077d9b91a197f2 Mon Sep 17 00:00:00 2001
From: Niklas Schilli <schillinik@yahoo.de>
Date: Thu, 19 Dec 2019 17:25:46 +0100
Subject: [PATCH] GH-969 Clipboard Changed (#720)

* Use SharedPreferences.Editor.Apply when editing to force disk write to be asynchronous (#637)

* GH-182 Color/Point/Rect/Size Extension Converters (#651)

* Add extension helpers for iOS and Android

* Add UWP colors and adjsut android colors.

* Add UWP Point/Rect/Size

* Rename and optimize!

* Add tests and color helpers!

* Fix unit test and add WithAlpha

* Cleanup iOS as it stores it from 0-1

* Tests are all green!

* Add generate-docs cmd :)

* Add docs config to all :)

* Additional clenaup for docs

* Added some docs

* Updated the mdoc target and regenerated the docs

* Allow for code reuse on macOS (#665)

Even though macOS is not yet officially supported, it is nice to reuse this code. macOS is exactly the same, except for this single property not supported.

* GH-196 Browser Customization (#646)

* Implemented GH-196

* Apply suggestions from code review: Naming

Renamed incorrectly spelled variables

Co-Authored-By: Mrnikbobjeff <schillinik@yahoo.de>

* Implemented GH-196

* Browser update work as requested. Using System.Drawing.Color now

* Adopted more review changes. Type forwarded.

* Review changes

* Made equals operator null safe, removed constructor

* Add documentation and simplify the API!

* Update viewmodel

* Back to 7.2

* GH-676 Require To Check GPS Location is Fake Or Not In GeoLocation (#677)

* Added  bool IsFromMockProvider in Location class

* Checkin

* csproj original

* Revert "csproj original"

This reverts commit 6302b95782006288862f0ce11100c81936baa7fb.

* Revert "Checkin"

This reverts commit 0881e4f12c36caecd08b3b9bb8757d8bd1025502.

* Revert "Added  bool IsFromMockProvider in Location class"

This reverts commit e56d9406cf0a92d24b04607afe81aef23aca696c.

* Revert the Xamarin.Essentials.csproj and Samples.Android.csproj to original;

Adjust the property IsFromMockProvider in Location.shared and LocationExetensions.

* Edited sample to show if the location is from moking provider.

* Update docs

* Fixes #694 (#699)

* Update the mdoc to use the new minimum for VS2019

* GH-126: Finish Shake Detector API (#693)

* Update CONTRIBUTING.md (#692)

* GH-126 Detect Shake API (#666)

* Added shaken support

* name vhange

* check-in

* doc update

* Implements the Shake API inside Accelerometer Class;
Change sample to AccelorometerViewModel

* Fix the sample project

* Update the docs

* Added Queue mechanism based off seismic with tests as well. Something is not  right yet with calulating isaccelerating.

* Finalize shake detection!!!

* Re-generated the docs.

* Fix the VM after merge

* GH-704 Handle duplicate item in keychain (#705)

* Update CONTRIBUTING.md (#692)

* #704 if we get a duplicate item try to remove and then re-add if possible.

* Initial commit Clipboard Change

* Implemented Clipboard listeners on iOS, tested on android and uwp and fixed other issues related to Visual Studio for Mac and Essentials support.

* Initial commit Clipboard Change

* Implemented Clipboard listeners on iOS, tested on android and uwp and fixed other issues related to Visual Studio for Mac and Essentials support.

* Naming fix

* UI improvements

* Docs update

* docs update part 2

* docs tool breaking fix

* reverted change to csproj
---
 Samples/Samples/View/ClipboardPage.xaml       |  1 +
 .../Samples/ViewModel/ClipboardViewModel.cs   | 25 ++++++++++++++-
 .../Clipboard/Clipboard.android.cs            | 20 +++++++++++-
 Xamarin.Essentials/Clipboard/Clipboard.ios.cs | 19 ++++++++++-
 ...lipboard.netstandard.tvos.watchos.tizen.cs |  6 ++++
 .../Clipboard/Clipboard.shared.cs             | 32 ++++++++++++++++++-
 Xamarin.Essentials/Clipboard/Clipboard.uwp.cs |  8 +++++
 .../xamarin-essentials-android.xml            |  1 +
 .../xamarin-essentials-ios.xml                |  1 +
 .../xamarin-essentials-uwp.xml                |  1 +
 .../en/FrameworksIndex/xamarin-essentials.xml |  1 +
 docs/en/Xamarin.Essentials/Clipboard.xml      | 19 +++++++++++
 12 files changed, 130 insertions(+), 4 deletions(-)

diff --git a/Samples/Samples/View/ClipboardPage.xaml b/Samples/Samples/View/ClipboardPage.xaml
index beeefc60f..b23535a55 100644
--- a/Samples/Samples/View/ClipboardPage.xaml
+++ b/Samples/Samples/View/ClipboardPage.xaml
@@ -17,6 +17,7 @@
                 <Entry Placeholder="Enter text..." Text="{Binding FieldValue}" />
                 <Button Text="Copy to clipboard" Command="{Binding CopyCommand}" />
                 <Button Text="Paste from clipboard" Command="{Binding PasteCommand}" />
+                <Label Text="{Binding LastCopied}" />
             </StackLayout>
         </ScrollView>
     </StackLayout>
diff --git a/Samples/Samples/ViewModel/ClipboardViewModel.cs b/Samples/Samples/ViewModel/ClipboardViewModel.cs
index 73dc02a0e..df2b7965c 100644
--- a/Samples/Samples/ViewModel/ClipboardViewModel.cs
+++ b/Samples/Samples/ViewModel/ClipboardViewModel.cs
@@ -1,4 +1,5 @@
-using System.Windows.Input;
+using System;
+using System.Windows.Input;
 using Xamarin.Essentials;
 using Xamarin.Forms;
 
@@ -7,6 +8,7 @@ namespace Samples.ViewModel
     class ClipboardViewModel : BaseViewModel
     {
         string fieldValue;
+        string lastCopied;
 
         public ClipboardViewModel()
         {
@@ -24,6 +26,27 @@ public string FieldValue
             set => SetProperty(ref fieldValue, value);
         }
 
+        public string LastCopied
+        {
+            get => lastCopied;
+            set => SetProperty(ref lastCopied, value);
+        }
+
+        public override void OnAppearing()
+        {
+            Clipboard.ClipboardContentChanged += OnClipboardContentChanged;
+        }
+
+        public override void OnDisappearing()
+        {
+            Clipboard.ClipboardContentChanged -= OnClipboardContentChanged;
+        }
+
+        void OnClipboardContentChanged(object sender, EventArgs args)
+        {
+            LastCopied = $"Last copied text at {DateTime.UtcNow:T}";
+        }
+
         async void OnCopy() => await Clipboard.SetTextAsync(FieldValue);
 
         async void OnPaste()
diff --git a/Xamarin.Essentials/Clipboard/Clipboard.android.cs b/Xamarin.Essentials/Clipboard/Clipboard.android.cs
index 7d8acecb7..d69118769 100644
--- a/Xamarin.Essentials/Clipboard/Clipboard.android.cs
+++ b/Xamarin.Essentials/Clipboard/Clipboard.android.cs
@@ -1,10 +1,14 @@
-using System.Threading.Tasks;
+using System;
+using System.Threading.Tasks;
 using Android.Content;
 
 namespace Xamarin.Essentials
 {
     public static partial class Clipboard
     {
+        static readonly Lazy<ClipboardChangeListener> clipboardListener
+            = new Lazy<ClipboardChangeListener>(() => new ClipboardChangeListener());
+
         static Task PlatformSetTextAsync(string text)
         {
             Platform.ClipboardManager.PrimaryClip = ClipData.NewPlainText("Text", text);
@@ -16,5 +20,19 @@ static bool PlatformHasText
 
         static Task<string> PlatformGetTextAsync()
             => Task.FromResult(Platform.ClipboardManager.PrimaryClip?.GetItemAt(0)?.Text);
+
+        static void StartClipboardListeners()
+            => Platform.ClipboardManager.AddPrimaryClipChangedListener(clipboardListener.Value);
+
+        static void StopClipboardListeners()
+            => Platform.ClipboardManager.RemovePrimaryClipChangedListener(clipboardListener.Value);
+    }
+
+    public class ClipboardChangeListener : Java.Lang.Object, ClipboardManager.IOnPrimaryClipChangedListener
+    {
+        public void OnPrimaryClipChanged()
+        {
+            Clipboard.ClipboardChangedInternal();
+        }
     }
 }
diff --git a/Xamarin.Essentials/Clipboard/Clipboard.ios.cs b/Xamarin.Essentials/Clipboard/Clipboard.ios.cs
index 569021e47..5f5ccb86f 100644
--- a/Xamarin.Essentials/Clipboard/Clipboard.ios.cs
+++ b/Xamarin.Essentials/Clipboard/Clipboard.ios.cs
@@ -1,4 +1,6 @@
-using System.Threading.Tasks;
+using System;
+using System.Threading.Tasks;
+using Foundation;
 using UIKit;
 
 namespace Xamarin.Essentials
@@ -11,10 +13,25 @@ static Task PlatformSetTextAsync(string text)
             return Task.CompletedTask;
         }
 
+        static NSObject observer;
+
         static bool PlatformHasText
             => UIPasteboard.General.HasStrings;
 
         static Task<string> PlatformGetTextAsync()
             => Task.FromResult(UIPasteboard.General.String);
+
+        static void StartClipboardListeners()
+        {
+            observer = NSNotificationCenter.DefaultCenter.AddObserver(
+                UIPasteboard.ChangedNotification,
+                ClipboardChangedObserver);
+        }
+
+        static void StopClipboardListeners()
+            => NSNotificationCenter.DefaultCenter.RemoveObserver(observer);
+
+        static void ClipboardChangedObserver(NSNotification notification)
+            => ClipboardChangedInternal();
     }
 }
diff --git a/Xamarin.Essentials/Clipboard/Clipboard.netstandard.tvos.watchos.tizen.cs b/Xamarin.Essentials/Clipboard/Clipboard.netstandard.tvos.watchos.tizen.cs
index 7f3b4d503..80a7274e2 100644
--- a/Xamarin.Essentials/Clipboard/Clipboard.netstandard.tvos.watchos.tizen.cs
+++ b/Xamarin.Essentials/Clipboard/Clipboard.netstandard.tvos.watchos.tizen.cs
@@ -12,5 +12,11 @@ static bool PlatformHasText
 
         static Task<string> PlatformGetTextAsync()
             => throw ExceptionUtils.NotSupportedOrImplementedException;
+
+        static void StartClipboardListeners()
+            => throw ExceptionUtils.NotSupportedOrImplementedException;
+
+        static void StopClipboardListeners()
+            => throw ExceptionUtils.NotSupportedOrImplementedException;
     }
 }
diff --git a/Xamarin.Essentials/Clipboard/Clipboard.shared.cs b/Xamarin.Essentials/Clipboard/Clipboard.shared.cs
index a490949de..e6c8d50f2 100644
--- a/Xamarin.Essentials/Clipboard/Clipboard.shared.cs
+++ b/Xamarin.Essentials/Clipboard/Clipboard.shared.cs
@@ -1,4 +1,5 @@
-using System.Threading.Tasks;
+using System;
+using System.Threading.Tasks;
 
 namespace Xamarin.Essentials
 {
@@ -12,5 +13,34 @@ public static bool HasText
 
         public static Task<string> GetTextAsync()
             => PlatformGetTextAsync();
+
+        public static event EventHandler<EventArgs> ClipboardContentChanged
+        {
+            add
+            {
+                var wasRunning = ClipboardContentChangedInternal != null;
+
+                ClipboardContentChangedInternal += value;
+
+                if (!wasRunning && ClipboardContentChangedInternal != null)
+                {
+                    StartClipboardListeners();
+                }
+            }
+
+            remove
+            {
+                var wasRunning = ClipboardContentChangedInternal != null;
+
+                ClipboardContentChangedInternal -= value;
+
+                if (wasRunning && ClipboardContentChangedInternal == null)
+                    StopClipboardListeners();
+            }
+        }
+
+        static event EventHandler<EventArgs> ClipboardContentChangedInternal;
+
+        internal static void ClipboardChangedInternal() => ClipboardContentChangedInternal?.Invoke(null, EventArgs.Empty);
     }
 }
diff --git a/Xamarin.Essentials/Clipboard/Clipboard.uwp.cs b/Xamarin.Essentials/Clipboard/Clipboard.uwp.cs
index 9678a3476..abcd90418 100644
--- a/Xamarin.Essentials/Clipboard/Clipboard.uwp.cs
+++ b/Xamarin.Essentials/Clipboard/Clipboard.uwp.cs
@@ -26,5 +26,13 @@ static Task<string> PlatformGetTextAsync()
                 ? clipboardContent.GetTextAsync().AsTask()
                 : Task.FromResult<string>(null);
         }
+
+        static void StartClipboardListeners()
+            => WindowsClipboard.ContentChanged += ClipboardChangedEventListener;
+
+        static void StopClipboardListeners()
+            => WindowsClipboard.ContentChanged -= ClipboardChangedEventListener;
+
+        static void ClipboardChangedEventListener(object sender, object val) => ClipboardChangedInternal();
     }
 }
diff --git a/docs/en/FrameworksIndex/xamarin-essentials-android.xml b/docs/en/FrameworksIndex/xamarin-essentials-android.xml
index ea05429db..d079b1248 100644
--- a/docs/en/FrameworksIndex/xamarin-essentials-android.xml
+++ b/docs/en/FrameworksIndex/xamarin-essentials-android.xml
@@ -127,6 +127,7 @@
       <Member Id="F:Xamarin.Essentials.BrowserTitleMode.Show" />
     </Type>
     <Type Name="Xamarin.Essentials.Clipboard" Id="T:Xamarin.Essentials.Clipboard">
+      <Member Id="E:Xamarin.Essentials.Clipboard.ClipboardContentChanged" />
       <Member Id="M:Xamarin.Essentials.Clipboard.GetTextAsync" />
       <Member Id="M:Xamarin.Essentials.Clipboard.SetTextAsync(System.String)" />
       <Member Id="P:Xamarin.Essentials.Clipboard.HasText" />
diff --git a/docs/en/FrameworksIndex/xamarin-essentials-ios.xml b/docs/en/FrameworksIndex/xamarin-essentials-ios.xml
index 6c55bd7b2..c8266d892 100644
--- a/docs/en/FrameworksIndex/xamarin-essentials-ios.xml
+++ b/docs/en/FrameworksIndex/xamarin-essentials-ios.xml
@@ -114,6 +114,7 @@
       <Member Id="F:Xamarin.Essentials.BrowserTitleMode.Show" />
     </Type>
     <Type Name="Xamarin.Essentials.Clipboard" Id="T:Xamarin.Essentials.Clipboard">
+      <Member Id="E:Xamarin.Essentials.Clipboard.ClipboardContentChanged" />
       <Member Id="M:Xamarin.Essentials.Clipboard.GetTextAsync" />
       <Member Id="M:Xamarin.Essentials.Clipboard.SetTextAsync(System.String)" />
       <Member Id="P:Xamarin.Essentials.Clipboard.HasText" />
diff --git a/docs/en/FrameworksIndex/xamarin-essentials-uwp.xml b/docs/en/FrameworksIndex/xamarin-essentials-uwp.xml
index e8606d888..9fd03cc6c 100644
--- a/docs/en/FrameworksIndex/xamarin-essentials-uwp.xml
+++ b/docs/en/FrameworksIndex/xamarin-essentials-uwp.xml
@@ -114,6 +114,7 @@
       <Member Id="F:Xamarin.Essentials.BrowserTitleMode.Show" />
     </Type>
     <Type Name="Xamarin.Essentials.Clipboard" Id="T:Xamarin.Essentials.Clipboard">
+      <Member Id="E:Xamarin.Essentials.Clipboard.ClipboardContentChanged" />
       <Member Id="M:Xamarin.Essentials.Clipboard.GetTextAsync" />
       <Member Id="M:Xamarin.Essentials.Clipboard.SetTextAsync(System.String)" />
       <Member Id="P:Xamarin.Essentials.Clipboard.HasText" />
diff --git a/docs/en/FrameworksIndex/xamarin-essentials.xml b/docs/en/FrameworksIndex/xamarin-essentials.xml
index 16131fc7d..e258c84d5 100644
--- a/docs/en/FrameworksIndex/xamarin-essentials.xml
+++ b/docs/en/FrameworksIndex/xamarin-essentials.xml
@@ -114,6 +114,7 @@
       <Member Id="F:Xamarin.Essentials.BrowserTitleMode.Show" />
     </Type>
     <Type Name="Xamarin.Essentials.Clipboard" Id="T:Xamarin.Essentials.Clipboard">
+      <Member Id="E:Xamarin.Essentials.Clipboard.ClipboardContentChanged" />
       <Member Id="M:Xamarin.Essentials.Clipboard.GetTextAsync" />
       <Member Id="M:Xamarin.Essentials.Clipboard.SetTextAsync(System.String)" />
       <Member Id="P:Xamarin.Essentials.Clipboard.HasText" />
diff --git a/docs/en/Xamarin.Essentials/Clipboard.xml b/docs/en/Xamarin.Essentials/Clipboard.xml
index 5ae388daf..77c2e7cbd 100644
--- a/docs/en/Xamarin.Essentials/Clipboard.xml
+++ b/docs/en/Xamarin.Essentials/Clipboard.xml
@@ -15,6 +15,25 @@
     <remarks></remarks>
   </Docs>
   <Members>
+    <Member MemberName="ClipboardContentChanged">
+      <MemberSignature Language="C#" Value="public static event EventHandler&lt;EventArgs&gt; ClipboardContentChanged;" />
+      <MemberSignature Language="ILAsm" Value=".event class System.EventHandler`1&lt;class System.EventArgs&gt; ClipboardContentChanged" />
+      <MemberSignature Language="DocId" Value="E:Xamarin.Essentials.Clipboard.ClipboardContentChanged" />
+      <MemberType>Event</MemberType>
+      <AssemblyInfo>
+        <AssemblyName>Xamarin.Essentials</AssemblyName>
+        <AssemblyVersion>1.0.0.0</AssemblyVersion>
+      </AssemblyInfo>
+      <ReturnValue>
+        <ReturnType>System.EventHandler&lt;System.EventArgs&gt;</ReturnType>
+      </ReturnValue>
+      <Docs>
+        <summary>Fires when the clipboard content changes.</summary>
+        <remarks>
+		  <para />
+		</remarks>
+      </Docs>
+    </Member>
     <Member MemberName="GetTextAsync">
       <MemberSignature Language="C#" Value="public static System.Threading.Tasks.Task&lt;string&gt; GetTextAsync ();" />
       <MemberSignature Language="ILAsm" Value=".method public static hidebysig class System.Threading.Tasks.Task`1&lt;string&gt; GetTextAsync() cil managed" />