From 7126f8cb6c00dea8936896e5b7c13ae3435d1a01 Mon Sep 17 00:00:00 2001
From: Thomas Galliker <thomas@bluewin.ch>
Date: Fri, 13 Sep 2024 09:22:22 +0200
Subject: [PATCH 1/4] Disable nullability in sample app

---
 Samples/CameraDemoApp/CameraDemoApp.csproj | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Samples/CameraDemoApp/CameraDemoApp.csproj b/Samples/CameraDemoApp/CameraDemoApp.csproj
index 129bb5e..2a81fbf 100644
--- a/Samples/CameraDemoApp/CameraDemoApp.csproj
+++ b/Samples/CameraDemoApp/CameraDemoApp.csproj
@@ -8,7 +8,7 @@
     <MauiVersion>8.0.82</MauiVersion>
     <SingleProject>true</SingleProject>
     <ImplicitUsings>enable</ImplicitUsings>
-    <Nullable>enable</Nullable>
+    <Nullable>disable</Nullable>
 
     <!-- Display name -->
     <ApplicationTitle>CameraDemoApp</ApplicationTitle>

From 1aa6ea379bd9ed289c85289e3e3dec4d3736e157 Mon Sep 17 00:00:00 2001
From: Thomas Galliker <thomas@bluewin.ch>
Date: Fri, 13 Sep 2024 10:29:10 +0200
Subject: [PATCH 2/4] Extend file picker demo with barcode result overlay

---
 .../Android/Services/BarcodeScanner.cs        | 11 +++++++--
 Samples/CameraDemoApp/MauiProgram.cs          |  1 +
 .../ViewModels/FilePickerViewModel.cs         | 12 ++++++----
 .../CameraDemoApp/Views/FilePickerPage.xaml   | 23 +++++++++++++++----
 4 files changed, 36 insertions(+), 11 deletions(-)

diff --git a/CameraScanner.Maui/Platforms/Android/Services/BarcodeScanner.cs b/CameraScanner.Maui/Platforms/Android/Services/BarcodeScanner.cs
index 03a8608..70752fe 100644
--- a/CameraScanner.Maui/Platforms/Android/Services/BarcodeScanner.cs
+++ b/CameraScanner.Maui/Platforms/Android/Services/BarcodeScanner.cs
@@ -123,8 +123,15 @@ internal static void ProcessBarcodeResult(Java.Lang.Object inputResults, HashSet
                 }
                 else
                 {
-                    previewRect = RectF.Zero;
-                    cornerPoints = [];
+                    previewRect = rectF.AsRectangleF();
+                    cornerPoints = barcode.GetCornerPoints()
+                       .Select(p =>
+                       {
+                           var pointF = new global::Android.Graphics.PointF(p);
+                           return pointF;
+                       })
+                       .Select(p => new Point(p.X, p.Y))
+                       .ToArray();
                 }
       
 
diff --git a/Samples/CameraDemoApp/MauiProgram.cs b/Samples/CameraDemoApp/MauiProgram.cs
index 20e31ef..81804cb 100644
--- a/Samples/CameraDemoApp/MauiProgram.cs
+++ b/Samples/CameraDemoApp/MauiProgram.cs
@@ -38,6 +38,7 @@ public static MauiApp CreateMauiApp()
             builder.Services.AddSingleton<INavigationService, MauiNavigationService>();
             builder.Services.AddSingleton<IDialogService, DialogService>();
             builder.Services.AddSingleton<ILauncher>(_ => Launcher.Default);
+            builder.Services.AddSingleton<IMediaPicker>(_ => MediaPicker.Default);
 
             // Register pages and view models
             builder.Services.AddTransient<MainPage>();
diff --git a/Samples/CameraDemoApp/ViewModels/FilePickerViewModel.cs b/Samples/CameraDemoApp/ViewModels/FilePickerViewModel.cs
index 300d09d..61a7165 100644
--- a/Samples/CameraDemoApp/ViewModels/FilePickerViewModel.cs
+++ b/Samples/CameraDemoApp/ViewModels/FilePickerViewModel.cs
@@ -2,28 +2,30 @@
 using CommunityToolkit.Mvvm.ComponentModel;
 using CommunityToolkit.Mvvm.Input;
 using Microsoft.Extensions.Logging;
-using Microsoft.Maui.Graphics.Platform;
 
 namespace CameraDemoApp.ViewModels
 {
     public class FilePickerViewModel : ObservableObject
     {
         private readonly ILogger logger;
+        private readonly IMediaPicker mediaPicker;
         private readonly IBarcodeScanner barcodeScanner;
 
-        private PlatformImage image;
+        private ImageSource image;
         private IAsyncRelayCommand pickPhotoCommand;
         private BarcodeResult[] barcodeResults;
 
         public FilePickerViewModel(
             ILogger<FilePickerViewModel> logger,
+            IMediaPicker mediaPicker,
             IBarcodeScanner barcodeScanner)
         {
             this.logger = logger;
+            this.mediaPicker = mediaPicker;
             this.barcodeScanner = barcodeScanner;
         }
 
-        public PlatformImage Image
+        public ImageSource Image
         {
             get => this.image;
             private set => this.SetProperty(ref this.image, value);
@@ -45,7 +47,7 @@ private async Task PickPhotoAsync()
             try
             {
                 var options = new MediaPickerOptions { Title = "Test picker" };
-                var fileResult = await MediaPicker.PickPhotoAsync(options);
+                var fileResult = await this.mediaPicker.PickPhotoAsync(options);
                 if (fileResult != null)
                 {
                     // save the file into local storage
@@ -57,6 +59,7 @@ private async Task PickPhotoAsync()
                     //await sourceStream.CopyToAsync(localFileStream);
 
                     var barcodeResults = await this.barcodeScanner.ScanFromImageAsync(fileResult);
+                    this.Image = ImageSource.FromFile(fileResult.FullPath);
                     this.BarcodeResults = barcodeResults.ToArray();
                 }
             }
@@ -64,6 +67,7 @@ private async Task PickPhotoAsync()
             {
                 this.logger.LogError(ex, "PickPhotoAsync failed with exception");
                 this.BarcodeResults = [];
+                this.Image = null;
             }
         }
     }
diff --git a/Samples/CameraDemoApp/Views/FilePickerPage.xaml b/Samples/CameraDemoApp/Views/FilePickerPage.xaml
index f7a2875..c265558 100644
--- a/Samples/CameraDemoApp/Views/FilePickerPage.xaml
+++ b/Samples/CameraDemoApp/Views/FilePickerPage.xaml
@@ -23,24 +23,37 @@
         RowDefinitions="*, Auto, Auto"
         RowSpacing="16">
 
-        <Image
-            Grid.Row="0"
-            Source="{Binding Image}" />
+        <Grid Grid.Row="0">
+            <Image
+                Grid.Row="0"
+                Source="{Binding Image}"
+                BackgroundColor="LightBlue" />
+            <c:BarcodeResultOverlay
+                Grid.Row="0"
+                BarcodeResults="{Binding BarcodeResults}"
+                InvalidateDrawableAfter="{x:Null}"
+                StrokeColor="Red"
+                StrokeSize="4">
+                <c:BarcodeResultOverlay.BarcodeDrawable>
+                    <c:BoundingBoxBarcodeDrawable />
+                </c:BarcodeResultOverlay.BarcodeDrawable>
+            </c:BarcodeResultOverlay>
+        </Grid>
 
         <VerticalStackLayout
             Grid.Row="1"
+            BackgroundColor="Yellow"
             BindableLayout.ItemTemplate="{StaticResource BarcodeResultItemTemplate}"
             BindableLayout.ItemsSource="{Binding BarcodeResults}" />
 
         <VerticalStackLayout
             Grid.Row="2"
+            BackgroundColor="LightGreen"
             VerticalOptions="Start">
-
             <Grid
                 RowDefinitions="Auto"
                 RowSpacing="8"
                 VerticalOptions="Fill">
-
                 <Button
                     Grid.Row="0"
                     Command="{Binding PickPhotoCommand}"

From be0663252f091bc5fca4b48e2f682de591d9be58 Mon Sep 17 00:00:00 2001
From: Thomas Galliker <thomas@bluewin.ch>
Date: Fri, 13 Sep 2024 10:29:50 +0200
Subject: [PATCH 3/4] Add new property InvalidateDrawableAfter (TimeSpan?) to
 set the delay after which the barcode result overlay is invalidated

---
 .../Controls/BarcodeResultOverlay.xaml.cs     | 67 ++++++++++++++++---
 1 file changed, 56 insertions(+), 11 deletions(-)

diff --git a/CameraScanner.Maui/Controls/BarcodeResultOverlay.xaml.cs b/CameraScanner.Maui/Controls/BarcodeResultOverlay.xaml.cs
index b15f267..6d11dcc 100644
--- a/CameraScanner.Maui/Controls/BarcodeResultOverlay.xaml.cs
+++ b/CameraScanner.Maui/Controls/BarcodeResultOverlay.xaml.cs
@@ -1,12 +1,11 @@
 using System.Windows.Input;
 using CameraScanner.Maui.Utils;
+using Microsoft.Maui.Graphics.Text;
 
 namespace CameraScanner.Maui.Controls
 {
     public partial class BarcodeResultOverlay : GraphicsView
     {
-        private static readonly TimeSpan ClearResultOverlayDelay = TimeSpan.FromMilliseconds(500);
-
         private readonly TaskDelayer taskDelayer;
 
         public BarcodeResultOverlay()
@@ -16,6 +15,18 @@ public BarcodeResultOverlay()
             this.Drawable = this.BarcodeDrawable;
         }
 
+        protected override void OnSizeAllocated(double width, double height)
+        {
+            base.OnSizeAllocated(width, height);
+            //UpdateDrawable(
+            //   this,
+            //   this.BarcodeResults,
+            //   this.StrokeSize,
+            //   this.StrokeColor,
+            //   this.TextColor,
+            //   this.InvalidateDrawableAfter);
+        }
+
         public static readonly BindableProperty BarcodeDrawableProperty = BindableProperty.Create(
             nameof(BarcodeDrawable),
             typeof(IBarcodeDrawable),
@@ -61,7 +72,8 @@ private static void OnBarcodeResultsPropertyChanged(BindableObject bindable, obj
                     barcodeResults,
                     barcodeResultOverlay.StrokeSize,
                     barcodeResultOverlay.StrokeColor,
-                    barcodeResultOverlay.TextColor);
+                    barcodeResultOverlay.TextColor,
+                    barcodeResultOverlay.InvalidateDrawableAfter);
             }
         }
 
@@ -89,7 +101,8 @@ private static void OnStrokeSizePropertyChanged(BindableObject bindable, object
                     barcodeResultOverlay.BarcodeResults,
                     strokeSize,
                     barcodeResultOverlay.StrokeColor,
-                    barcodeResultOverlay.TextColor);
+                    barcodeResultOverlay.TextColor,
+                    barcodeResultOverlay.InvalidateDrawableAfter);
             }
         }
 
@@ -117,7 +130,8 @@ private static void OnStrokeColorPropertyChanged(BindableObject bindable, object
                     barcodeResultOverlay.BarcodeResults,
                     barcodeResultOverlay.StrokeSize,
                     strokeColor,
-                    barcodeResultOverlay.TextColor);
+                    barcodeResultOverlay.TextColor,
+                    barcodeResultOverlay.InvalidateDrawableAfter);
             }
         }
 
@@ -145,7 +159,8 @@ private static void OnTextColorPropertyChanged(BindableObject bindable, object o
                     barcodeResultOverlay.BarcodeResults,
                     barcodeResultOverlay.StrokeSize,
                     barcodeResultOverlay.StrokeColor,
-                    textColor);
+                    textColor,
+                    barcodeResultOverlay.InvalidateDrawableAfter);
             }
         }
 
@@ -155,17 +170,47 @@ public Color TextColor
             set => this.SetValue(TextColorProperty, value);
         }
 
+        public static readonly BindableProperty InvalidateDrawableAfterProperty = BindableProperty.Create(
+            nameof(InvalidateDrawableAfter),
+            typeof(TimeSpan?),
+            typeof(BarcodeResultOverlay),
+            TimeSpan.FromMilliseconds(500),
+            propertyChanged: OnInvalidateDrawableAfterPropertyChanged);
+
+
+        private static void OnInvalidateDrawableAfterPropertyChanged(BindableObject bindable, object oldValue, object newValue)
+        {
+            var barcodeResultOverlay = (BarcodeResultOverlay)bindable;
+
+            UpdateDrawable(
+                 barcodeResultOverlay,
+                 barcodeResultOverlay.BarcodeResults,
+                 barcodeResultOverlay.StrokeSize,
+                 barcodeResultOverlay.StrokeColor,
+                 barcodeResultOverlay.TextColor,
+                 newValue as TimeSpan?);
+        }
+
+        public TimeSpan? InvalidateDrawableAfter
+        {
+            get => (TimeSpan?)this.GetValue(InvalidateDrawableAfterProperty);
+            set => this.SetValue(InvalidateDrawableAfterProperty, value);
+        }
+
         private static void UpdateDrawable(BarcodeResultOverlay barcodeResultOverlay,
-            BarcodeResult[] barcodeResults, float strokeSize, Color strokeColor, Color textColor)
+            BarcodeResult[] barcodeResults, float strokeSize, Color strokeColor, Color textColor, TimeSpan? invalidateDrawableAfter)
         {
             barcodeResultOverlay.BarcodeDrawable.Update(barcodeResults, strokeSize, strokeColor, textColor);
             barcodeResultOverlay.Invalidate();
 
-            barcodeResultOverlay.taskDelayer.RunWithDelay(ClearResultOverlayDelay, () =>
+            if (invalidateDrawableAfter is TimeSpan delay)
             {
-                barcodeResultOverlay.BarcodeDrawable.Reset();
-                MainThread.BeginInvokeOnMainThread(barcodeResultOverlay.Invalidate);
-            });
+                barcodeResultOverlay.taskDelayer.RunWithDelay(delay, () =>
+                {
+                    barcodeResultOverlay.BarcodeDrawable.Reset();
+                    MainThread.BeginInvokeOnMainThread(barcodeResultOverlay.Invalidate);
+                });
+            }
         }
 
         private void TapGestureRecognizer_OnTapped(object sender, TappedEventArgs e)

From f0d4642e9a84a45e21be03241e3c0cc9ba6ef544 Mon Sep 17 00:00:00 2001
From: Thomas Galliker <thomas@bluewin.ch>
Date: Fri, 13 Sep 2024 15:44:39 +0200
Subject: [PATCH 4/4] Update file picker layout

---
 .../Resources/Styles/Converters.xaml          |  2 +
 .../ViewModels/FilePickerViewModel.cs         | 29 +++++++---
 .../CameraDemoApp/Views/FilePickerPage.xaml   | 58 ++++++++++++-------
 .../Views/FilePickerPage.xaml.cs              | 14 +++++
 .../BarcodeResultItemTemplate.xaml            | 23 +++++++-
 5 files changed, 93 insertions(+), 33 deletions(-)

diff --git a/Samples/CameraDemoApp/Resources/Styles/Converters.xaml b/Samples/CameraDemoApp/Resources/Styles/Converters.xaml
index 4974a12..d6842b7 100644
--- a/Samples/CameraDemoApp/Resources/Styles/Converters.xaml
+++ b/Samples/CameraDemoApp/Resources/Styles/Converters.xaml
@@ -22,4 +22,6 @@
         FalseValue="Pause"
         TrueValue="Resume" />
 
+    <c:StringIsNotNullOrEmptyConverter x:Key="StringIsNotNullOrEmptyConverter" />
+
 </ResourceDictionary>
\ No newline at end of file
diff --git a/Samples/CameraDemoApp/ViewModels/FilePickerViewModel.cs b/Samples/CameraDemoApp/ViewModels/FilePickerViewModel.cs
index 61a7165..5539a5e 100644
--- a/Samples/CameraDemoApp/ViewModels/FilePickerViewModel.cs
+++ b/Samples/CameraDemoApp/ViewModels/FilePickerViewModel.cs
@@ -34,7 +34,26 @@ public ImageSource Image
         public BarcodeResult[] BarcodeResults
         {
             get => this.barcodeResults;
-            private set => this.SetProperty(ref this.barcodeResults, value);
+            private set
+            {
+                if (this.SetProperty(ref this.barcodeResults, value))
+                {
+                    this.OnPropertyChanged(nameof(this.BarcodeResultsCountText));
+                }
+            }
+        }
+
+        public string BarcodeResultsCountText
+        {
+            get
+            {
+                if (this.BarcodeResults is not BarcodeResult[] barcodeResults)
+                {
+                    return null;
+                }
+
+                return string.Format("Number of barcodes found: {0}", barcodeResults.Length);
+            }
         }
 
         public IAsyncRelayCommand PickPhotoCommand
@@ -50,14 +69,6 @@ private async Task PickPhotoAsync()
                 var fileResult = await this.mediaPicker.PickPhotoAsync(options);
                 if (fileResult != null)
                 {
-                    // save the file into local storage
-                    //var localFilePath = Path.Combine(FileSystem.CacheDirectory, fileResult.FileName);
-
-                    //using var sourceStream = await fileResult.OpenReadAsync();
-                    //using var localFileStream = File.OpenWrite(localFilePath);
-
-                    //await sourceStream.CopyToAsync(localFileStream);
-
                     var barcodeResults = await this.barcodeScanner.ScanFromImageAsync(fileResult);
                     this.Image = ImageSource.FromFile(fileResult.FullPath);
                     this.BarcodeResults = barcodeResults.ToArray();
diff --git a/Samples/CameraDemoApp/Views/FilePickerPage.xaml b/Samples/CameraDemoApp/Views/FilePickerPage.xaml
index c265558..bcd1940 100644
--- a/Samples/CameraDemoApp/Views/FilePickerPage.xaml
+++ b/Samples/CameraDemoApp/Views/FilePickerPage.xaml
@@ -20,46 +20,60 @@
 
     <Grid
         Padding="16"
-        RowDefinitions="*, Auto, Auto"
-        RowSpacing="16">
+        RowDefinitions="*, Auto"
+        RowSpacing="8">
 
         <Grid Grid.Row="0">
             <Image
                 Grid.Row="0"
                 Source="{Binding Image}"
-                BackgroundColor="LightBlue" />
-            <c:BarcodeResultOverlay
+                BackgroundColor="{StaticResource Gray100}"
+                SizeChanged="Image_SizeChanged"
+                HorizontalOptions="Fill"
+                VerticalOptions="Start" />
+
+            <!--  BarcodeResultOverlay does not (yet) properly work with photo picker  -->
+            <!--<c:BarcodeResultOverlay
                 Grid.Row="0"
                 BarcodeResults="{Binding BarcodeResults}"
                 InvalidateDrawableAfter="{x:Null}"
+                SizeChanged="BarcodeResultOverlay_SizeChanged"
                 StrokeColor="Red"
                 StrokeSize="4">
                 <c:BarcodeResultOverlay.BarcodeDrawable>
                     <c:BoundingBoxBarcodeDrawable />
                 </c:BarcodeResultOverlay.BarcodeDrawable>
-            </c:BarcodeResultOverlay>
+            </c:BarcodeResultOverlay>-->
         </Grid>
 
         <VerticalStackLayout
             Grid.Row="1"
-            BackgroundColor="Yellow"
-            BindableLayout.ItemTemplate="{StaticResource BarcodeResultItemTemplate}"
-            BindableLayout.ItemsSource="{Binding BarcodeResults}" />
+            Spacing="8">
 
-        <VerticalStackLayout
-            Grid.Row="2"
-            BackgroundColor="LightGreen"
-            VerticalOptions="Start">
-            <Grid
-                RowDefinitions="Auto"
-                RowSpacing="8"
-                VerticalOptions="Fill">
-                <Button
-                    Grid.Row="0"
-                    Command="{Binding PickPhotoCommand}"
-                    Text="Pick Photo"
-                    HorizontalOptions="Fill" />
-            </Grid>
+            <ScrollView MaximumHeightRequest="200">
+                <VerticalStackLayout
+                    BindableLayout.ItemTemplate="{StaticResource BarcodeResultItemTemplate}"
+                    BindableLayout.ItemsSource="{Binding BarcodeResults}"
+                    Spacing="4" />
+            </ScrollView>
+
+            <Label
+                FontAttributes="Bold"
+                IsVisible="{Binding BarcodeResultsCountText, Converter={StaticResource StringIsNotNullOrEmptyConverter}}"
+                Text="{Binding BarcodeResultsCountText}" />
+
+            <VerticalStackLayout VerticalOptions="Start">
+                <Grid
+                    RowDefinitions="Auto"
+                    RowSpacing="8"
+                    VerticalOptions="Fill">
+                    <Button
+                        Grid.Row="0"
+                        Command="{Binding PickPhotoCommand}"
+                        Text="Pick Photo"
+                        HorizontalOptions="Fill" />
+                </Grid>
+            </VerticalStackLayout>
         </VerticalStackLayout>
     </Grid>
 </ContentPage>
\ No newline at end of file
diff --git a/Samples/CameraDemoApp/Views/FilePickerPage.xaml.cs b/Samples/CameraDemoApp/Views/FilePickerPage.xaml.cs
index 910056b..fe09ee1 100644
--- a/Samples/CameraDemoApp/Views/FilePickerPage.xaml.cs
+++ b/Samples/CameraDemoApp/Views/FilePickerPage.xaml.cs
@@ -1,3 +1,5 @@
+using System.Diagnostics;
+
 namespace CameraDemoApp.Views;
 
 public partial class FilePickerPage : ContentPage
@@ -6,4 +8,16 @@ public FilePickerPage()
     {
         this.InitializeComponent();
     }
+
+    private void Image_SizeChanged(object sender, EventArgs e)
+    {
+        var visualElement = (VisualElement)sender;
+        Debug.WriteLine($"Image_SizeChanged: w:{visualElement.Width} x h:{visualElement.Height}");
+    }
+
+    private void BarcodeResultOverlay_SizeChanged(object sender, EventArgs e)
+    {
+        var visualElement = (VisualElement)sender;
+        Debug.WriteLine($"BarcodeResultOverlay_SizeChanged: w:{visualElement.Width} x h:{visualElement.Height}");
+    }
 }
\ No newline at end of file
diff --git a/Samples/CameraDemoApp/Views/ItemTemplates/BarcodeResultItemTemplate.xaml b/Samples/CameraDemoApp/Views/ItemTemplates/BarcodeResultItemTemplate.xaml
index 193a878..19b7bb8 100644
--- a/Samples/CameraDemoApp/Views/ItemTemplates/BarcodeResultItemTemplate.xaml
+++ b/Samples/CameraDemoApp/Views/ItemTemplates/BarcodeResultItemTemplate.xaml
@@ -4,20 +4,31 @@
     xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
     xmlns:c="http://camerascanner.maui"
     x:Class="CameraDemoApp.Views.ItemTemplates.BarcodeResultItemTemplate"
-    x:DataType="c:BarcodeResult">
+    x:DataType="c:BarcodeResult"
+    BackgroundColor="{StaticResource Secondary}">
+
+    <ContentView.Resources>
+        <ResourceDictionary>
+            <Style TargetType="Label">
+                <Setter Property="FontFamily" Value="IBMPlexMonoRegular" />
+            </Style>
+        </ResourceDictionary>
+    </ContentView.Resources>
 
     <Grid
         ColumnDefinitions="Auto, *"
         ColumnSpacing="8"
-        RowDefinitions="Auto, Auto"
+        RowDefinitions="Auto, Auto, Auto"
         RowSpacing="4">
         <Label
             Grid.Row="0"
             Grid.Column="0"
+            FontAttributes="Bold"
             Text="RawValue" />
         <Label
             Grid.Row="0"
             Grid.Column="1"
+            FontAttributes="Bold"
             Text="{Binding RawValue}" />
         <Label
             Grid.Row="1"
@@ -27,5 +38,13 @@
             Grid.Row="1"
             Grid.Column="1"
             Text="{Binding BarcodeFormat}" />
+        <Label
+            Grid.Row="2"
+            Grid.Column="0"
+            Text="BarcodeType" />
+        <Label
+            Grid.Row="2"
+            Grid.Column="1"
+            Text="{Binding BarcodeType}" />
     </Grid>
 </ContentView>