Avalonia学习（二十九）-仪表

Avalonia制作仪表盘，把控件给大家演示一下，Avalonia有三类自定义控件，分别是用户控件、模版控件、自主控件。前面已经很多用户控件了，这个是演示模版控件，另外一种不知道哪种情况下使用。

前端代码：

<Styles xmlns="https://github.com/avaloniaui"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  xmlns:local="clr-namespace:GaugeAvalonia.Views;assembly=GaugeAvalonia"
    x:CompileBindings="False"
  >
  <Design.PreviewWith>
        <Border Padding="20">
            <!-- Add Controls for Previewer Here -->
        </Border>
    </Design.PreviewWith>
 
  <Style  Selector="local|ArcGauge">
    <Setter Property="Background" Value="#646464"/>
    <Setter Property="Foreground" Value="Black"/>
    <Setter Property="Template">
      <Setter.Value>
        <ControlTemplate TargetType="{x:Type local:ArcGauge}">
          <Border Margin="10">
            <Grid Width="{Binding RelativeSource={RelativeSource Self},Path=Height}">
              <Ellipse Fill="#FF3B3B3B"/>
              <Grid RenderTransformOrigin="0.5,0.5" Margin="2">
                <Grid.RenderTransform>
                  <TransformGroup>
                    <RotateTransform  Angle="{Binding Angle}"/>
                    </TransformGroup>
                </Grid.RenderTransform>
                <Ellipse Width="16" Height="14" Fill="Orange" VerticalAlignment="Top" >
                  <Ellipse.Effect>
                    <BlurEffect Radius="12"/>
                  </Ellipse.Effect>
                </Ellipse>
              </Grid>
 
              <Grid x:Name="bdGrid" Margin="12" UseLayoutRounding="True" ClipToBounds="True">
                <Ellipse>
                  <Ellipse.Fill>
                    <RadialGradientBrush>
                      <GradientStop Color="#4D000000"/>
                    </RadialGradientBrush>
                  </Ellipse.Fill>
                </Ellipse>
                <Grid>
                  <Grid.ColumnDefinitions>
                    <ColumnDefinition/>
                    <ColumnDefinition Width="2*"/>
                    <ColumnDefinition/>
                  </Grid.ColumnDefinitions>
                  <Grid.RowDefinitions>
                    <RowDefinition/>
                    <RowDefinition Height="2*"/>
                    <RowDefinition/>
                  </Grid.RowDefinitions>
                  <Ellipse Stroke="#464646" StrokeThickness="1" Grid.Column="1" Grid.Row="1"/>
                  <Ellipse Stroke="#959595" Margin="4" StrokeThickness="6" Grid.Column="1" Grid.Row="1"/>
                  <Ellipse Stroke="#464646" Margin="14" StrokeThickness="1" Grid.Column="1" Grid.Row="1"/>
                </Grid>
                <Grid>
                  <Grid.RowDefinitions>
                    <RowDefinition/>
                    <RowDefinition/>
                  </Grid.RowDefinitions>
                  <Path  Data="M5,0 5,0 10,120 0,120z" Fill="#0FA9CE" Stretch="Uniform" Margin="0 30 0 0"  HorizontalAlignment="Center">
                    <Path.RenderTransform>
                      <TransformGroup>
                        <RotateTransform    Angle="{Binding Path=Angle, Mode=TwoWay}"/>
                      </TransformGroup>
                    </Path.RenderTransform>
                  </Path>
                </Grid>
                <Ellipse Width="28" Height="28" Fill="Black">
                  <Ellipse.Effect>
                  <!--<DropShadowEffect Color="#0FA9CE" ShadowDepth="0" Direction="0" BlurRadius="16"/>-->
                  </Ellipse.Effect>
                </Ellipse>
                <Border VerticalAlignment="Bottom" BorderBrush="#10ABD1" BorderThickness="2" Margin="0 0 0 12" Background="Black" Padding="8 2" HorizontalAlignment="Center">
                  <TextBlock Text="{Binding Value,RelativeSource={RelativeSource Mode=TemplatedParent}}" FontSize="16" Width="30" TextAlignment="Center" Foreground="White" FontWeight="Bold"/>
                </Border>
              </Grid>
            </Grid>
          </Border>
        </ControlTemplate>
      </Setter.Value>
    </Setter>
  </Style>
 
</Styles>

后台代码：

using Avalonia;
using Avalonia.Controls;
using Avalonia.Controls.Shapes;
using Avalonia.Media;
using System.Collections.Generic;
using System.ComponentModel;
using Avalonia.Controls.Templates;
using Avalonia.Controls.Primitives;
using System.Linq;
 
namespace GaugeAvalonia.Views
{
    public class ArcGauge: TemplatedControl
    {
      
        Grid bdGrid;
 
        static ArcGauge()
        {
           
           // DefaultStyleKeyProperty.OverrideMetadata(typeof(ArcGauge), new FrameworkPropertyMetadata(typeof(ArcGauge)));
        }
        
        public ArcGauge()
        {
            this.Loaded += ArcGauge_Loaded;
            //Width = 200;
            //Height = 200;
            SetCurrentValue(ValueProperty, 0d);
            SetCurrentValue(MinValueProperty, 0d);
            SetCurrentValue(MaxValueProperty, 100d);
        }
 
        private void ArcGauge_Loaded(object? sender, Avalonia.Interactivity.RoutedEventArgs e)
        {
            InitTick();
        }
 
 
 
 
 
 
 
 
 
        public override void Render(DrawingContext context)
        {
           
            base.Render(context);
          
            bdGrid = (Grid)this.GetTemplateChildren().Where(x => x.Name == "bdGrid").First();
            Refresh();
        
 
        }
        private void InitTick()
        {
            // 画大刻度
            for (int i = 0; i < 9; i++)
            {
                Line line = new Line();
                line.StartPoint = new Point(0, 0);
                line.EndPoint=new Point(0, 12);
                line.HorizontalAlignment= Avalonia.Layout.HorizontalAlignment
                    .Center;
             
                line.Stroke = Brushes.White;
                line.StrokeThickness = 2;
                line.RenderTransformOrigin = RelativePoint.Center;
              
                line.RenderTransform = new RotateTransform() { Angle = -140 + i * 35 };
                 bdGrid.Children.Add(line);
                DrawText();
            }            // 画小刻度
            for (int i = 0; i < 8; i++)
            {
                var start = -140 + 35 * i + 3.5;
                for (int j = 0; j < 9; j++)
                {
                    Line line = new Line();
                    line.StartPoint = new Point(0, 0);
                    line.EndPoint = new Point(0, 6);
                   
                    line.Stroke = Brushes.White;
                    line.StrokeThickness = 1;
                    line.HorizontalAlignment = Avalonia.Layout.HorizontalAlignment .Center;
                    line.RenderTransformOrigin = RelativePoint.Center;
                    line.RenderTransform = new RotateTransform() { Angle = start + j * 3.5 };
                    bdGrid.Children.Add(line);
                }
            }
        }
        List<TextBlock> textLabels = new List<TextBlock>();
        private void DrawText()
        {
            foreach (var item in textLabels)
            {
                  bdGrid.Children.Remove(item);
            }
            textLabels.Clear();
            var per = MaxValue / 8;
            for (int i = 0; i < 9; i++)
            {
                TextBlock textBlock = new TextBlock();
                textBlock.Text = $"{MinValue + (per * i)}";
                textBlock.HorizontalAlignment =  Avalonia.Layout.HorizontalAlignment.Center;
                textBlock.RenderTransformOrigin = RelativePoint.Center;
                textBlock.RenderTransform = new RotateTransform() { Angle = -140 + i * 35 };
                textBlock.Margin = new Thickness(12);
                textBlock.Foreground = Brushes.White;
                bdGrid.Children.Add(textBlock);
                textLabels.Add(textBlock);
            }
        }
 
 
       
        //public static readonly StyledProperty<IBrush> BackgroundProperty =
        //   AvaloniaProperty.Register<ArcGauge, IBrush>(nameof(Value));
        //public IBrush Background
        //{
        //    get
        //    {
        //        return GetValue(BackgroundProperty);
        //    }
        //    set
        //    {
        //        SetValue(BackgroundProperty, value);
        //    }
        //}
 
        //public static readonly StyledProperty<IBrush> ForegroundProperty =
        // AvaloniaProperty.Register<ArcGauge, IBrush>(nameof(Value));
        //public IBrush Foreground
        //{
        //    get
        //    {
        //        return GetValue(ForegroundProperty);
        //    }
        //    set
        //    {
        //        SetValue(ForegroundProperty, value);
        //    }
       // }
 
 
 
        [Category("值设定")]
        public double Value
        {
            get { return (double)GetValue(ValueProperty); }
            set { SetValue(ValueProperty, value); }
        }
        public static readonly StyledProperty<double> ValueProperty =
            AvaloniaProperty.Register<ArcGauge, double>(nameof(Value), coerce: OnValueChanged);
 
        private static double OnValueChanged(AvaloniaObject @object, double arg2)
        {
            ArcGauge gauge= @object  as ArcGauge;
            gauge.Refresh();
            return arg2;
        }
 
        [Category("值设定")]
        public double MinValue
        {
            get { return (double)GetValue(MinValueProperty); }
            set { SetValue(MinValueProperty, value); }
        }
        public static readonly StyledProperty<double> MinValueProperty =
            AvaloniaProperty.Register<ArcGauge, double>(nameof(MinValue), coerce: OnValueChanged);
        public double MaxValue
        {
            get { return (double)GetValue(MaxValueProperty); }
            set { SetValue(MaxValueProperty, value); }
        }
        public static readonly StyledProperty<double> MaxValueProperty =
           AvaloniaProperty.Register<ArcGauge, double>(nameof(MaxValue), coerce: OnValueChanged);
 
 
        public double Angle
        {
            get { return (double)GetValue(AngleProperty); }
            set { SetValue(AngleProperty, value); }
        }
        public static readonly StyledProperty<double> AngleProperty =
         AvaloniaProperty.Register<ArcGauge, double>(nameof(Angle));
 
 
      
        private void Refresh()
        {
 
           
            if (Value > MaxValue)
            {
                Angle = 140;
 
            }
            else if (Value < MinValue)
            {
                Angle = -140;
 
            }
            else
            {
                var range = MaxValue - MinValue;
                var process = Value / range;
                var tAngle = process * 280 - 140;
                Angle = tAngle;
 
            }
 
            
        }
    }
}
 

运行效果：

目前Avalonia的内容也不知道该演示什么了。估计博文会更新慢了。