演示修改颜色

Author: lindexi

demo/AvaloniaInkCanvasDemo/ViewModels/MainViewModel.cs

@@ -1,5 +1,22 @@
-namespace AvaloniaInkCanvasDemo.ViewModels;
+using System.Collections.ObjectModel;
+using Avalonia.Media;
+
+namespace AvaloniaInkCanvasDemo.ViewModels;
 
 public class MainViewModel : ViewModelBase
 {
+    public MainViewModel()
+    {
+        SolidColorBrushCollection =
+        [
+            Brushes.Red,
+            Brushes.Black,
+            Brushes.Green,
+            Brushes.Blue,
+            Brushes.Orange,
+            Brushes.Purple
+        ];
+    }
+
+    public ObservableCollection<IBrush> SolidColorBrushCollection { get; }
 }

demo/AvaloniaInkCanvasDemo/Views/MainView.axaml

@@ -12,12 +12,28 @@
          to set the actual DataContext for runtime, set the DataContext property in code (look at App.axaml.cs) -->
         <vm:MainViewModel />
     </Design.DataContext>
-    <Grid RowDefinitions="*,Auto"
+    <Grid RowDefinitions="*,Auto,Auto"
         Background="Gray">
         <Border Background="White">
             <inking:InkCanvas x:Name="InkCanvas"/>
         </Border>
-        <StackPanel Grid.Row="1" Orientation="Horizontal" Margin="10,10,10,10">
+
+        <StackPanel Grid.Row="1" Orientation="Horizontal" Margin="10,10,10,0">
+            <ListBox SelectedIndex="0" Background="Transparent" ItemsSource="{Binding SolidColorBrushCollection}" SelectionChanged="SelectingItemsControl_OnSelectionChanged">
+                <ListBox.ItemsPanel>
+                    <ItemsPanelTemplate>
+                        <StackPanel Orientation="Horizontal"></StackPanel>
+                    </ItemsPanelTemplate>
+                </ListBox.ItemsPanel>
+                <ListBox.ItemTemplate>
+                    <DataTemplate DataType="IBrush">
+                        <Ellipse Fill="{Binding .}" Width="20" Height="20"></Ellipse>
+                    </DataTemplate>
+                </ListBox.ItemTemplate>
+            </ListBox>
+        </StackPanel>
+        
+        <StackPanel Grid.Row="2" Orientation="Horizontal" Margin="10,10,10,10">
             <Button x:Name="PenModeButton" Click="PenModeButton_OnClick">Pen</Button>
             <Button x:Name="EraserModeButton" Margin="10,0,0,0" Click="EraserModeButton_OnClick">Eraser</Button>
             <Button x:Name="SwitchRendererButton" Margin="10,0,0,0" Click="SwitchRendererButton_OnClick">Switch Renderer</Button>

demo/AvaloniaInkCanvasDemo/Views/MainView.axaml.cs

@@ -1,5 +1,6 @@
 using Avalonia.Controls;
 using Avalonia.Interactivity;
+using Avalonia.Media;
 using Avalonia.Skia;
 using AvaloniaInkCanvasDemo.Views.ErasingView;
 using DotNetCampus.Inking;
@@ -65,4 +66,15 @@ private void SaveStrokeAsSvgButton_OnClick(object? sender, RoutedEventArgs e)
             skCanvas.DrawPath(stroke.Path, skPaint);
         }
     }
+
+    private void SelectingItemsControl_OnSelectionChanged(object? sender, SelectionChangedEventArgs e)
+    {
+        if (e.AddedItems.Count is 1)
+        {
+            if (e.AddedItems[0] is ISolidColorBrush brush)
+            {
+                InkCanvas.AvaloniaSkiaInkCanvas.Settings.InkColor = brush.Color.ToSKColor();
+            }
+        }
+    }
 }