From 6c9a0ab6b2e3855e95685719d6acb7e7398bd03b Mon Sep 17 00:00:00 2001
From: Zeljko Predjeskovic <Zeljko.Predjeskovic@opti-q.com>
Date: Sun, 9 Oct 2022 17:43:09 +0200
Subject: [PATCH] Share pdf file to this app and render it Android/IOS

---
 .github/workflows/build.yml                   | 25 ++++++
 .github/workflows/test.yml                    | 22 +++++
 iCL.DocumentConverter.sln                     |  2 +-
 src/DocumentPicker.Droid/MainActivity.cs      | 81 ++++++++++++++++++-
 .../Properties/AssemblyInfo.cs                |  2 +-
 src/DocumentPicker.IOS/AppDelegate.cs         | 24 +++++-
 src/DocumentPicker.IOS/Info.plist             | 15 ++++
 .../DocumentConverter.Plugin.csproj           |  5 +-
 .../Shared/FileSharing/SharedStream.cs        | 22 +++++
 src/DocumentPicker.Sample/App.xaml.cs         |  2 +
 .../DocumentPicker.Samples.csproj             |  7 ++
 .../DocumentPickerPage.xaml                   |  6 +-
 .../DocumentPickerPage.xaml.cs                | 41 +++++-----
 .../NotifyVisibility/IObserver.cs             | 11 +++
 .../NotifyVisibility/ISubject.cs              | 13 +++
 .../NotifyVisibility/SharedVisibles.cs        | 29 +++++++
 .../NotifyVisibility/Visibles.cs              | 36 +++++++++
 .../PartialViews/ShareButton.xaml             | 10 +++
 .../PartialViews/ShareButton.xaml.cs          | 45 +++++++++++
 .../PartialViews/ShareNotification.xaml       | 10 +++
 .../PartialViews/ShareNotification.xaml.cs    | 41 ++++++++++
 21 files changed, 416 insertions(+), 33 deletions(-)
 create mode 100644 .github/workflows/build.yml
 create mode 100644 .github/workflows/test.yml
 create mode 100644 src/DocumentPicker.Plugin/Shared/FileSharing/SharedStream.cs
 create mode 100644 src/DocumentPicker.Sample/NotifyVisibility/IObserver.cs
 create mode 100644 src/DocumentPicker.Sample/NotifyVisibility/ISubject.cs
 create mode 100644 src/DocumentPicker.Sample/NotifyVisibility/SharedVisibles.cs
 create mode 100644 src/DocumentPicker.Sample/NotifyVisibility/Visibles.cs
 create mode 100644 src/DocumentPicker.Sample/PartialViews/ShareButton.xaml
 create mode 100644 src/DocumentPicker.Sample/PartialViews/ShareButton.xaml.cs
 create mode 100644 src/DocumentPicker.Sample/PartialViews/ShareNotification.xaml
 create mode 100644 src/DocumentPicker.Sample/PartialViews/ShareNotification.xaml.cs

diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
new file mode 100644
index 0000000..d2b5b5b
--- /dev/null
+++ b/.github/workflows/build.yml
@@ -0,0 +1,25 @@
+name: Build
+on:
+  push:
+    branches: [ feature/github_workflow ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  Build:
+    runs-on: [windows-latest]
+
+    steps:
+    - uses: actions/checkout@v2
+      
+    - name: Setup MSBuild
+      uses: microsoft/setup-msbuild@v1
+
+    - name: Setup NuGet
+      uses: NuGet/setup-nuget@v1.0.5
+
+    - name: Restore NuGet packages
+      run: nuget restore iCL.DocumentConverter.sln
+
+    - name: Build the Solution
+      run: msbuild iCL.DocumentConverter.sln /p:Configuration=Release
\ No newline at end of file
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
new file mode 100644
index 0000000..337ad53
--- /dev/null
+++ b/.github/workflows/test.yml
@@ -0,0 +1,22 @@
+name: Test
+
+on:
+  push:
+    branches: [ feature/github_workflow ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  Build:
+    runs-on: [windows-latest]
+
+    steps:
+    - uses: actions/checkout@v2
+      with:
+        dotnet-version: 6.0.x
+
+    - name: Setup MSBuild
+      uses: microsoft/setup-msbuild@v1
+
+    - name: Execute unit tests
+      run: dotnet test
\ No newline at end of file
diff --git a/iCL.DocumentConverter.sln b/iCL.DocumentConverter.sln
index 8731614..fa91ed8 100644
--- a/iCL.DocumentConverter.sln
+++ b/iCL.DocumentConverter.sln
@@ -19,7 +19,7 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "DocumentConverter.Tests", "
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "DocumentPicker.Droid", "src\DocumentPicker.Droid\DocumentPicker.Droid.csproj", "{F7830ABA-CFCF-481C-9AB7-D5973FFE9B85}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "DocumentConverter.Benchmark", "tests\DocumentConverter.Benchmark\DocumentConverter.Benchmark.csproj", "{0275CD62-6BB8-4DBF-91B1-EB54CB18A184}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "DocumentConverter.Benchmark", "tests\DocumentConverter.Benchmark\DocumentConverter.Benchmark.csproj", "{0275CD62-6BB8-4DBF-91B1-EB54CB18A184}"
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
diff --git a/src/DocumentPicker.Droid/MainActivity.cs b/src/DocumentPicker.Droid/MainActivity.cs
index 968332e..0b21d03 100644
--- a/src/DocumentPicker.Droid/MainActivity.cs
+++ b/src/DocumentPicker.Droid/MainActivity.cs
@@ -1,30 +1,109 @@
-using Android.App;
+using System.IO;
+using Android.App;
+using Android.Content;
 using Android.Content.PM;
+using Android.Net;
 using Android.OS;
+using Android.Provider;
 using Android.Runtime;
+using Android.Views;
+using Android.Widget;
+using DocumentConverter.Plugin.Shared;
+using DocumentConverter.Plugin.Shared.FileSharing;
 using DocumentConverter.Plugin.Shared.StreamProvider;
 using DocumentPicker.Samples;
+using DocumentPicker.Samples.NotifyVisibility;
 using Svg;
 
 namespace DocumentPicker.Droid
 {
     [Activity(Label = "@string/app_name", Theme = "@style/AppTheme", MainLauncher = true, ConfigurationChanges = ConfigChanges.ScreenSize | ConfigChanges.Orientation)]
+    [IntentFilter(new[] { Intent.ActionSend }, Categories = new[] { Intent.CategoryDefault }, DataMimeType = @"application/pdf")]
     public class MainActivity : Xamarin.Forms.Platform.Android.FormsAppCompatActivity
     {
         protected override void OnCreate(Bundle bundle)
         {
             base.OnCreate(bundle);
+            LoadApp(bundle);
+
+
+            if (Intent.ActionSend.Equals(Intent?.Action) &&
+                Intent.Type != null &&
+                "application/pdf".Equals(Intent.Type))
+            {
+                // This is just an example of the data stored in the extras 
+                var uriFromExtras = Intent.GetParcelableExtra(Intent.ExtraStream) as Android.Net.Uri;
+                var subject = Intent.GetStringExtra(Intent.ExtraSubject);
+
+                // Get the info from ClipData 
+                var pdf = Intent.ClipData.GetItemAt(0);
+
+                // Open a stream from the URI 
+                var pdfStream = ContentResolver.OpenInputStream(pdf.Uri);
+
+                SharedStream.Instance = pdfStream;
+                SharedVisibles.ShowShareViews();
+
+                //Save off the path and description here
+                //Remove dialog and navigate back to app or browser that shared                 
+                //the link
+            }
+        }
+
+        private void LoadApp(Bundle bundle)
+        {
             FFImageLoading.Forms.Platform.CachedImageRenderer.Init(true);
             Xamarin.Essentials.Platform.Init(this, bundle);
             Xamarin.Forms.Forms.Init(this, bundle);
             SvgPlatform.Init();
             LoadApplication(new App());
         }
+
+        //private Stream GetFileStream(Uri uri)
+        //{
+
+        //    // Get the info from ClipData 
+        //    var pdf = Intent.ClipData.GetItemAt(0);
+
+        //    // Open a stream from the URI 
+        //    var pdfStream = ContentResolver.OpenInputStream(pdf.Uri);
+
+
+        //    return pdfStream;
+        //}
         public override void OnRequestPermissionsResult(int requestCode, string[] permissions, [GeneratedEnum] Android.Content.PM.Permission[] grantResults)
         {
             Xamarin.Essentials.Platform.OnRequestPermissionsResult(requestCode, permissions, grantResults);
 
             base.OnRequestPermissionsResult(requestCode, permissions, grantResults);
         }
+
+        //private void handleSendUrl()
+        //{
+        //    var view = new LinearLayout(this) { Orientation = Orientation.Vertical };
+        //    var url = Intent.GetStringExtra(Intent.ExtraText);
+
+        //    var urlTextView = new TextView(this) { Gravity = GravityFlags.Center };
+        //    urlTextView.Text = url;
+
+        //    view.AddView(urlTextView);
+        //    var description = new EditText(this) { Gravity = GravityFlags.Top };
+        //    view.AddView(description);
+
+        //    new AlertDialog.Builder(this)
+        //        .SetTitle("Save a URL Link")
+        //        .SetMessage("Type a description for your link")
+        //        .SetView(view)
+        //        .SetPositiveButton("Add", (dialog, whichButton) =>
+        //        {
+        //            var desc = description.Text;
+        //            //Save off the url and description here
+        //            //Remove dialog and navigate back to app or browser that shared                 
+        //            //the link
+        //            FinishAndRemoveTask();
+        //            FinishAffinity();
+        //        })
+        //        .Show();
+        //}
     }
 }
\ No newline at end of file
diff --git a/src/DocumentPicker.Droid/Properties/AssemblyInfo.cs b/src/DocumentPicker.Droid/Properties/AssemblyInfo.cs
index a152854..968b47a 100644
--- a/src/DocumentPicker.Droid/Properties/AssemblyInfo.cs
+++ b/src/DocumentPicker.Droid/Properties/AssemblyInfo.cs
@@ -9,7 +9,7 @@
 [assembly: AssemblyTitle("DocumentPicker.Droid")]
 [assembly: AssemblyDescription("")]
 [assembly: AssemblyConfiguration("")]
-[assembly: AssemblyCompany("")]
+[assembly: AssemblyCompany("Optiq")]
 [assembly: AssemblyProduct("DocumentPicker.Droid")]
 [assembly: AssemblyCopyright("Copyright ©  2018")]
 [assembly: AssemblyTrademark("")]
diff --git a/src/DocumentPicker.IOS/AppDelegate.cs b/src/DocumentPicker.IOS/AppDelegate.cs
index 5221b07..604e105 100644
--- a/src/DocumentPicker.IOS/AppDelegate.cs
+++ b/src/DocumentPicker.IOS/AppDelegate.cs
@@ -1,8 +1,12 @@
-using DocumentConverter.Plugin.Shared.StreamProvider;
+using DocumentConverter.Plugin.Shared.FileSharing;
+using DocumentConverter.Plugin.Shared.StreamProvider;
 using DocumentPicker.Samples;
+using DocumentPicker.Samples.NotifyVisibility;
 using Foundation;
 using Svg;
 using UIKit;
+using Xamarin.Essentials;
+using Xamarin.Forms;
 
 namespace DocumentPicker.IOS
 {
@@ -20,15 +24,29 @@ public override UIWindow Window
         }
 
         public override bool FinishedLaunching(UIApplication app, NSDictionary options)
+        {
+            LoadApp();
+            return base.FinishedLaunching(app, options);
+        }
+
+        public override bool OpenUrl(UIApplication app, NSUrl url, NSDictionary options)
+        {
+            SharedStream.Instance = System.IO.File.Open(url.Path, System.IO.FileMode.OpenOrCreate, System.IO.FileAccess.ReadWrite);
+
+            SharedVisibles.ShowShareViews();
+
+            return true;
+        }
+
+        private void LoadApp()
         {
             FFImageLoading.Forms.Platform.CachedImageRenderer.Init();
             Xamarin.Forms.Forms.Init();
             SvgPlatform.Init();
             LoadApplication(new App());
-
-            return base.FinishedLaunching(app, options);
         }
 
+
         public override void OnResignActivation(UIApplication application)
         {
             // Invoked when the application is about to move from active to inactive state.
diff --git a/src/DocumentPicker.IOS/Info.plist b/src/DocumentPicker.IOS/Info.plist
index 57ba747..e621e2b 100644
--- a/src/DocumentPicker.IOS/Info.plist
+++ b/src/DocumentPicker.IOS/Info.plist
@@ -10,6 +10,21 @@
     <string>1.0</string>
     <key>CFBundleVersion</key>
     <string>1.0</string>
+	<key>CFBundleDocumentTypes</key>
+	<array>
+		<dict>
+			<key>CFBundleTypeName</key>
+			<string>PDF</string>
+			<key>CFBundleTypeRole</key>
+			<string>Viewer</string>
+			<key>LSHandlerRank</key>
+			<string>Alternate</string>
+			<key>LSItemContentTypes</key>
+			<array>
+				<string>com.adobe.pdf</string>
+			</array>
+		</dict>
+	</array>
     <key>LSRequiresIPhoneOS</key>
     <true/>
     <key>MinimumOSVersion</key>
diff --git a/src/DocumentPicker.Plugin/DocumentConverter.Plugin.csproj b/src/DocumentPicker.Plugin/DocumentConverter.Plugin.csproj
index bd0f1f8..37ef8f8 100644
--- a/src/DocumentPicker.Plugin/DocumentConverter.Plugin.csproj
+++ b/src/DocumentPicker.Plugin/DocumentConverter.Plugin.csproj
@@ -1,4 +1,4 @@
-<Project Sdk="MSBuild.Sdk.Extras/2.0.54">
+<Project Sdk="MSBuild.Sdk.Extras/2.0.54">
 	
 	<PropertyGroup>
 		<TargetFrameworks>netstandard2.0;MonoAndroid90;Xamarin.iOS10;uap10.0.17763</TargetFrameworks>
@@ -17,11 +17,8 @@
 
 	<ItemGroup Condition=" $(TargetFramework.StartsWith('uap')) ">
 		<Compile Include="Platforms\UniversalWindows\**\*.cs" />
-
 		<PackageReference Include="Microsoft.NETCore.UniversalWindowsPlatform" Version="6.2.14" />
-
 		<Folder Include="Platforms\UniversalWindows\" />
 	</ItemGroup>
 
-
 </Project>
diff --git a/src/DocumentPicker.Plugin/Shared/FileSharing/SharedStream.cs b/src/DocumentPicker.Plugin/Shared/FileSharing/SharedStream.cs
new file mode 100644
index 0000000..19a68bb
--- /dev/null
+++ b/src/DocumentPicker.Plugin/Shared/FileSharing/SharedStream.cs
@@ -0,0 +1,22 @@
+using System;
+using System.IO;
+using DocumentConverter.Plugin.Shared.StreamProvider;
+
+namespace DocumentConverter.Plugin.Shared.FileSharing
+{
+    public static class SharedStream
+    {
+        private static Stream _stream;
+
+        public static Stream Instance
+        {
+            get => _stream;
+            set => _stream = value;
+        }
+
+        public static void DisposeStream()
+        {
+            Instance.Dispose();
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/DocumentPicker.Sample/App.xaml.cs b/src/DocumentPicker.Sample/App.xaml.cs
index 77fa4fa..bb05526 100644
--- a/src/DocumentPicker.Sample/App.xaml.cs
+++ b/src/DocumentPicker.Sample/App.xaml.cs
@@ -1,4 +1,5 @@
 using DocumentConverter.Plugin.Shared.StreamProvider;
+using DocumentPicker.Samples.NotifyVisibility;
 using Xamarin.Forms;
 using Xamarin.Forms.Xaml;
 
@@ -13,6 +14,7 @@ public App()
 
             CustomStreamProviderInitializer.Init();
             MainPage = new NavigationPage(new DocumentPickerPage());
+            SharedVisibles.Init();
         }
 
         protected override void OnStart()
diff --git a/src/DocumentPicker.Sample/DocumentPicker.Samples.csproj b/src/DocumentPicker.Sample/DocumentPicker.Samples.csproj
index db7a39c..286023a 100644
--- a/src/DocumentPicker.Sample/DocumentPicker.Samples.csproj
+++ b/src/DocumentPicker.Sample/DocumentPicker.Samples.csproj
@@ -2,6 +2,7 @@
 
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
+    <LangVersion>latest</LangVersion>
   </PropertyGroup>
 
 	<ItemGroup>
@@ -19,6 +20,12 @@
 		<EmbeddedResource Update="DocumentPickerPage.xaml">
 			<Generator>MSBuild:UpdateDesignTimeXaml</Generator>
 		</EmbeddedResource>
+		<EmbeddedResource Update="PartialViews\ShareButton.xaml">
+		  <Generator>MSBuild:UpdateDesignTimeXaml</Generator>
+		</EmbeddedResource>
+		<EmbeddedResource Update="PartialViews\ShareNotification.xaml">
+		  <Generator>MSBuild:UpdateDesignTimeXaml</Generator>
+		</EmbeddedResource>
 	</ItemGroup>
 
 </Project>
diff --git a/src/DocumentPicker.Sample/DocumentPickerPage.xaml b/src/DocumentPicker.Sample/DocumentPickerPage.xaml
index a76de90..5404459 100644
--- a/src/DocumentPicker.Sample/DocumentPickerPage.xaml
+++ b/src/DocumentPicker.Sample/DocumentPickerPage.xaml
@@ -1,16 +1,18 @@
 <?xml version="1.0" encoding="utf-8" ?>
 <ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
              xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
+             xmlns:mynamespace="clr-namespace:DocumentPicker.Samples.PartialViews;assembly=DocumentPicker.Samples"
              x:Class="DocumentPicker.Samples.DocumentPickerPage"             
              xmlns:ios="clr-namespace:Xamarin.Forms.PlatformConfiguration.iOSSpecific;assembly=Xamarin.Forms.Core"
              ios:Page.UseSafeArea="True">
 
 
     <StackLayout Spacing="10" Padding="10">
+        <Label Text="Document Picker"></Label>
+        <mynamespace:ShareNotification x:Name="Notification"></mynamespace:ShareNotification>
         <Grid x:Name="Grid">
-
         </Grid>
-        <Button x:Name="pickDocument" Text="Pick Document"/>
+        <mynamespace:ShareButton x:Name="shareButton"></mynamespace:ShareButton>
         <StackLayout Orientation="Horizontal">
         </StackLayout>
         <ScrollView>
diff --git a/src/DocumentPicker.Sample/DocumentPickerPage.xaml.cs b/src/DocumentPicker.Sample/DocumentPickerPage.xaml.cs
index 0408eab..b5b24a1 100644
--- a/src/DocumentPicker.Sample/DocumentPickerPage.xaml.cs
+++ b/src/DocumentPicker.Sample/DocumentPickerPage.xaml.cs
@@ -9,9 +9,12 @@
 using Image = Xamarin.Forms.Image;
 using System.Threading.Tasks;
 using DocumentConverter.Plugin.Shared;
+using DocumentConverter.Plugin.Shared.FileSharing;
 using DocumentConverter.Plugin.Shared.Picker;
 using DocumentConverter.Plugin.Shared.StreamProvider;
+using DocumentPicker.Samples.PartialViews;
 using Xamarin.Essentials;
+using DocumentPicker.Samples.NotifyVisibility;
 
 namespace DocumentPicker.Samples
 {
@@ -22,7 +25,6 @@ public partial class DocumentPickerPage : ContentPage
         private readonly IFilePicker _filePicker;
         private readonly ICustomStreamProvider _streamProvider;
 
-
         ObservableCollection<string> filePaths = new ObservableCollection<string>();
         
         public DocumentPickerPage()
@@ -35,24 +37,22 @@ public DocumentPickerPage()
 
             filePaths.CollectionChanged += Files_CollectionChanged;
 
-            pickDocument.Clicked += async (sender, args) =>
-            {
-                var pickerOptions = new DocumentPickerOptions()
-                {
-                    PickerTitle = "Please pick a pdf file",
-                    FileTypes = new Dictionary<DevicePlatform, IEnumerable<string>>
-                    {
-                        { DevicePlatform.iOS, new[] { "com.adobe.pdf" } }, // or general UTType values
-                        { DevicePlatform.Android, new[] { "application/pdf", "application/png", "application/svg" } },
-                        { DevicePlatform.UWP, new[] { ".pdf" } }
-                    }
-                };
 
-                var filePath = await _filePicker.PickAsync(pickerOptions);
+            shareButton.OnCLickedShare = () =>
+            {
+                SharedVisibles.HideShareViews();
+                filePaths.Add("new" + Guid.NewGuid());
+                return true;
+            };
 
-                if(filePath != null)
+            var pickerOptions = new DocumentPickerOptions()
+            {
+                PickerTitle = "Please pick a pdf file",
+                FileTypes = new Dictionary<DevicePlatform, IEnumerable<string>>
                 {
-                    filePaths.Add(filePath);
+                    { DevicePlatform.iOS, new[] { "com.adobe.pdf" } }, // or general UTType values
+                    { DevicePlatform.Android, new[] { "application/pdf", "application/png", "application/svg" } },
+                    { DevicePlatform.UWP, new[] { ".pdf" } }
                 }
             };
         }
@@ -71,8 +71,6 @@ private async void Files_CollectionChanged(object sender, System.Collections.Spe
 
             List<string> pageStrings = new List<string>();
 
-            int page = 1;
-
             var progressBar = new ProgressBar();
             Grid.Children.Add(progressBar);
 
@@ -85,19 +83,20 @@ private async void Files_CollectionChanged(object sender, System.Collections.Spe
 
                 try
                 {
-                    var inputStream = await _streamProvider.OpenReadWriteAsync(file);
-                    var outputStream = new MemoryStream();
+                    using var inputStream = SharedStream.Instance;
+                    using var outputStream = new MemoryStream();
 
                     await _converterService.ConvertPdfToSvgAsync(inputStream, outputStream);
                     outputStream.Seek(0, SeekOrigin.Begin);
 
                     var svgDoc = SvgDocument.Open<SvgDocument>(outputStream);
                     
+                    SharedStream.DisposeStream();
 
                     await progressBar.ProgressTo(0.75, 200, Easing.Linear);
                     using (var f = File.Create(newPath))
                     {
-                        var bitMap = svgDoc.DrawAllContents();
+                        using var bitMap = svgDoc.DrawAllContents();
                         bitMap.SavePng(f, 100);
                         await progressBar.ProgressTo(1, 50, Easing.Linear);
                     }
diff --git a/src/DocumentPicker.Sample/NotifyVisibility/IObserver.cs b/src/DocumentPicker.Sample/NotifyVisibility/IObserver.cs
new file mode 100644
index 0000000..18c1650
--- /dev/null
+++ b/src/DocumentPicker.Sample/NotifyVisibility/IObserver.cs
@@ -0,0 +1,11 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace DocumentPicker.Samples.NotifyVisibility
+{
+    public interface IObserver
+    {
+        void Update(ISubject subject);
+         }
+}
diff --git a/src/DocumentPicker.Sample/NotifyVisibility/ISubject.cs b/src/DocumentPicker.Sample/NotifyVisibility/ISubject.cs
new file mode 100644
index 0000000..9dd5ab3
--- /dev/null
+++ b/src/DocumentPicker.Sample/NotifyVisibility/ISubject.cs
@@ -0,0 +1,13 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace DocumentPicker.Samples.NotifyVisibility
+{
+    public interface ISubject
+    {
+        void Attach(IObserver observer);
+
+        void Notify();
+    }
+}
diff --git a/src/DocumentPicker.Sample/NotifyVisibility/SharedVisibles.cs b/src/DocumentPicker.Sample/NotifyVisibility/SharedVisibles.cs
new file mode 100644
index 0000000..cdd3721
--- /dev/null
+++ b/src/DocumentPicker.Sample/NotifyVisibility/SharedVisibles.cs
@@ -0,0 +1,29 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace DocumentPicker.Samples.NotifyVisibility
+{
+    public static class SharedVisibles
+    {
+        private static Visibles _visibles;
+        public static Visibles Visibles
+        {
+            get => _visibles ?? (_visibles = new Visibles());
+        }
+
+        public static void Init()
+        {
+            Visibles.IsVisible = false;
+        }
+
+        public static void ShowShareViews()
+        {
+            Visibles.IsVisible = true;
+        }
+        public static void HideShareViews()
+        {
+            Visibles.IsVisible = false;
+        }
+    }
+}
diff --git a/src/DocumentPicker.Sample/NotifyVisibility/Visibles.cs b/src/DocumentPicker.Sample/NotifyVisibility/Visibles.cs
new file mode 100644
index 0000000..6550493
--- /dev/null
+++ b/src/DocumentPicker.Sample/NotifyVisibility/Visibles.cs
@@ -0,0 +1,36 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace DocumentPicker.Samples.NotifyVisibility
+{
+    public class Visibles : ISubject
+    {
+
+        private List<IObserver> _observers;
+
+        private bool _isVisible;
+
+        public bool IsVisible
+        {
+            get => _isVisible;
+            set
+            {
+                _isVisible = value;
+                Notify();
+            }
+        }
+        public void Attach(IObserver observer)
+        {
+            if(_observers == null)
+                _observers = new List<IObserver>();
+
+            _observers.Add(observer);
+        }
+
+        public void Notify()
+        {
+            _observers.ForEach(o => o.Update(this));
+        }
+    }
+}
diff --git a/src/DocumentPicker.Sample/PartialViews/ShareButton.xaml b/src/DocumentPicker.Sample/PartialViews/ShareButton.xaml
new file mode 100644
index 0000000..aaf0cd9
--- /dev/null
+++ b/src/DocumentPicker.Sample/PartialViews/ShareButton.xaml
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ContentView xmlns="http://xamarin.com/schemas/2014/forms" 
+             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
+             x:Class="DocumentPicker.Samples.PartialViews.ShareButton">
+  <ContentView.Content>
+      <StackLayout>
+          <Button x:Name="shareButton" Text="Share!"/>
+        </StackLayout>
+  </ContentView.Content>
+</ContentView>
\ No newline at end of file
diff --git a/src/DocumentPicker.Sample/PartialViews/ShareButton.xaml.cs b/src/DocumentPicker.Sample/PartialViews/ShareButton.xaml.cs
new file mode 100644
index 0000000..42c8a85
--- /dev/null
+++ b/src/DocumentPicker.Sample/PartialViews/ShareButton.xaml.cs
@@ -0,0 +1,45 @@
+using DocumentPicker.Samples.NotifyVisibility;
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+using Xamarin.Forms;
+using Xamarin.Forms.Xaml;
+
+namespace DocumentPicker.Samples.PartialViews
+{
+    [XamlCompilation(XamlCompilationOptions.Compile)]
+    public partial class ShareButton : ContentView, IObserver
+    {
+
+        private bool _isVisible;
+
+        public Func<bool> OnCLickedShare { get; set; }
+
+        public bool IsVisible
+        {
+            get => _isVisible;
+            set
+            {
+                _isVisible = value;
+                shareButton.IsVisible = value;
+                OnPropertyChanged("shareButton");
+            }
+        }
+
+        public ShareButton()
+        {
+            InitializeComponent();
+            SharedVisibles.Visibles.Attach(this);
+            shareButton.Clicked += (sender, args) => { OnCLickedShare.Invoke(); };
+        }
+
+        public void Update(ISubject subject)
+        { 
+            IsVisible = SharedVisibles.Visibles.IsVisible;
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/DocumentPicker.Sample/PartialViews/ShareNotification.xaml b/src/DocumentPicker.Sample/PartialViews/ShareNotification.xaml
new file mode 100644
index 0000000..1aed2bf
--- /dev/null
+++ b/src/DocumentPicker.Sample/PartialViews/ShareNotification.xaml
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ContentView xmlns="http://xamarin.com/schemas/2014/forms" 
+             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
+             x:Class="DocumentPicker.Samples.PartialViews.ShareNotification">
+  <ContentView.Content>
+        <StackLayout BackgroundColor="Green" x:Name="Layout">
+          <Label TextColor="White" x:Name="Label" Text="File to share!!"/>
+      </StackLayout>
+  </ContentView.Content>
+</ContentView>
\ No newline at end of file
diff --git a/src/DocumentPicker.Sample/PartialViews/ShareNotification.xaml.cs b/src/DocumentPicker.Sample/PartialViews/ShareNotification.xaml.cs
new file mode 100644
index 0000000..83e1981
--- /dev/null
+++ b/src/DocumentPicker.Sample/PartialViews/ShareNotification.xaml.cs
@@ -0,0 +1,41 @@
+using DocumentPicker.Samples.NotifyVisibility;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+using Xamarin.Forms;
+using Xamarin.Forms.Xaml;
+
+namespace DocumentPicker.Samples.PartialViews
+{
+    [XamlCompilation(XamlCompilationOptions.Compile)]
+    public partial class ShareNotification : ContentView, IObserver
+    {
+
+        private bool _isVisible;
+
+        public bool IsVisible
+        {
+            get => _isVisible;
+            set
+            {
+                _isVisible = value;
+                Layout.IsVisible = value;
+                OnPropertyChanged("Layout");
+            }
+        }
+
+        public ShareNotification()
+        {
+            InitializeComponent();
+            SharedVisibles.Visibles.Attach(this);
+        }
+
+        public void Update(ISubject subject)
+        { 
+            IsVisible = SharedVisibles.Visibles.IsVisible;
+        }
+    }
+}
\ No newline at end of file