WPF 笔记 九 通过UserControl实例说明依赖属性和绑定

通过UserControl实例说明依赖属性和绑定

看一个简单例子

https://www.cnblogs.com/dotnet261010/p/6286475.html

先绘制原始circularprogressbar

<UserControl x:Class="WpfUITest1.Controls.CircularProgressBar"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:WpfUITest1.Controls"
             mc:Ignorable="d" 
             d:DesignHeight="150" d:DesignWidth="150">
    <Grid Height="{Binding RelativeSource={RelativeSource Self},Path=Width}" Name="layout">
        <Ellipse Width="{Binding ElementName=layout,Path=Width}"
                 Height="{Binding ElementName=layout,Path=Width}"
                 StrokeThickness="6" Stroke="#EEE" >
            <Ellipse.Effect>
                <DropShadowEffect ShadowDepth="0" Direction="0" Color="White" BlurRadius="5"/>
            </Ellipse.Effect>
        </Ellipse>
        <Path Name="path" Data="M75 3A75 75 0 0 1 147 75" StrokeThickness="4" Stroke="Orange"
              StrokeStartLineCap="Round" StrokeEndLineCap="Round"/>
        <!--M75 3A75 75 0 0 1 147 75-->
        <Viewbox Margin="20" >
            <TextBlock Foreground="White" VerticalAlignment="Center" HorizontalAlignment="Center">
                <Run Text="25"></Run>
                <Run Text="%"></Run>
            </TextBlock>
            <!--{Binding Value,RelativeSource={RelativeSource AncestorType=UserControl,Mode=FindAncestor}}-->
        </Viewbox>
    </Grid>
</UserControl>

例子1：使用依赖属性，添加进度值

后台

    public partial class CircularProgressBar : UserControl
    {


        public double Value
        {
            get { return (double)GetValue(ValueProperty); }
            set { SetValue(ValueProperty, value); }
        }

        public static DependencyProperty ValueProperty { get; } = DependencyProperty.Register("Value", typeof(double), typeof(CircularProgressBar), new PropertyMetadata(default(double), new PropertyChangedCallback(OnPropertyChanged)));

        public Brush BackColor
        {
            get { return (Brush)GetValue(BackColorProperty); }
            set { SetValue(BackColorProperty, value); }
        }
        public static readonly DependencyProperty BackColorProperty =
            DependencyProperty.Register("BackColor", typeof(Brush), typeof(CircularProgressBar), new PropertyMetadata(Brushes.LightGray));

        public Brush ForeColor
        {
            get { return (Brush)GetValue(ForeColorProperty); }
            set { SetValue(ForeColorProperty, value); }
        }
        public static readonly DependencyProperty ForeColorProperty =
            DependencyProperty.Register("ForeColor", typeof(Brush), typeof(CircularProgressBar), new PropertyMetadata(Brushes.Orange));
        public CircularProgressBar()
        {
            InitializeComponent();
            this.SizeChanged += CircularProgressBar_SizeChanged;
        }

        private void CircularProgressBar_SizeChanged(object sender, SizeChangedEventArgs e)
        {
            UpdateValue();
        }

        private static void OnPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            (d as CircularProgressBar).UpdateValue();
        }

        private void UpdateValue()
        {
            this.layout.Width=Math.Min(RenderSize.Width, RenderSize.Height);
            double radius = Math.Min(RenderSize.Width, RenderSize.Height) / 2;
            if (radius <= 0)
                return;
            double newValue = this.Value % 100.0;
            double newX = 0.0, newY = 0.0;
            newX = radius + (radius - 3) * Math.Cos((newValue * 3.6 - 90) * Math.PI / 180);
            newY = radius + (radius - 3) * Math.Sin((newValue * 3.6 - 90) * Math.PI / 180);

            //M75 3A75 75 0 0 1 147 75

            string pathDataStr = "M{0} 3A{1} {1} 0 {4} 1 {2} {3}";
            pathDataStr = string.Format(pathDataStr,
                radius + 0.01,
                radius - 3,
                newX,
                newY,
                newValue < 50 && newValue > 0 ? 0 : 1
                );
            var converter = TypeDescriptor.GetConverter(typeof(Geometry));
            this.path.Data = (Geometry)converter.ConvertFrom(pathDataStr);
        }
    }

前端 绑定

<UserControl x:Class="WpfUITest1.Controls.CircularProgressBar"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:WpfUITest1.Controls"
             mc:Ignorable="d" 
             d:DesignHeight="150" d:DesignWidth="150">
    <Grid Height="{Binding RelativeSource={RelativeSource Self},Path=Width}" Name="layout">
        <Ellipse Width="{Binding ElementName=layout,Path=Width}"
                 Height="{Binding ElementName=layout,Path=Width}"
                 StrokeThickness="6" Stroke="{Binding BackColor,RelativeSource={RelativeSource AncestorType=UserControl,Mode=FindAncestor}}" >
            <Ellipse.Effect>
                <DropShadowEffect ShadowDepth="0" Direction="0" Color="White" BlurRadius="5"/>
            </Ellipse.Effect>
        </Ellipse>
        <Path Name="path"  StrokeThickness="4" Stroke="{Binding ForeColor,RelativeSource={RelativeSource AncestorType=UserControl,Mode=FindAncestor}}"
              StrokeStartLineCap="Round" StrokeEndLineCap="Round"/>
        <!--M75 3A75 75 0 0 1 147 75-->
        <Viewbox Margin="20" >
            <TextBlock Foreground="White" VerticalAlignment="Center" HorizontalAlignment="Center">
                <Run Text="{Binding Value,RelativeSource={RelativeSource AncestorType=UserControl,Mode=FindAncestor}}"></Run>
                <Run Text="%"></Run>
            </TextBlock>
            <!--{Binding Value,RelativeSource={RelativeSource AncestorType=UserControl,Mode=FindAncestor}}-->
        </Viewbox>
    </Grid>
</UserControl>

如何使用

<UserControl
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:WpfUITest1.View"
             xmlns:Controls="clr-namespace:WpfUITest1.Controls" x:Class="WpfUITest1.View.SystemMonitor"
             mc:Ignorable="d" 
             d:DesignHeight="450" d:DesignWidth="800">

    <Grid>
        <Canvas/>
        <Grid VerticalAlignment="Top">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="320"/>
                <ColumnDefinition/>
                <ColumnDefinition Width="300"/>
            </Grid.ColumnDefinitions>


            <Grid Grid.Column="2">
                <Grid.RowDefinitions>
                    <RowDefinition Height="auto"/>
                    <RowDefinition Height="auto"/>
                    <RowDefinition Height="auto"/>
                    <RowDefinition Height="auto"/>
                    <RowDefinition Height="auto"/>
                    <RowDefinition Height="auto"/>
                </Grid.RowDefinitions>
                <TextBlock Text="系统总览" Foreground="White" FontSize="16" HorizontalAlignment="Right" Margin="0,0,20,0"/>

                <UniformGrid Rows="1" Grid.Row="1" Margin="0,40,0,0">
                    <StackPanel>
                        <TextBlock Text="监控值" HorizontalAlignment="Center" Foreground="#99FFFFFF"/>
                        <Controls:CircularProgressBar Value="70" Width="60" Height="90" ForeColor="#20c9b4"/>
                        <!--ForeColor="#20c9b4"-->
                    </StackPanel>
                    <StackPanel>
                        <TextBlock Text="监控值" HorizontalAlignment="Center" Foreground="#99FFFFFF"/>
                        <Controls:CircularProgressBar Value="50" Width="60" Height="90"/>
                    </StackPanel>
                    <StackPanel>
                        <TextBlock Text="监控值" HorizontalAlignment="Center" Foreground="#99FFFFFF"/>
                        <Controls:CircularProgressBar Value="30" Width="60" Height="90" ForeColor="#38baec"/>
                    </StackPanel>
                </UniformGrid>
            </Grid>
        </Grid>
    </Grid>
</UserControl>