一．前言
申明：WPF自定义控件与样式是一个系列文章，前后是有些关联的，但大多是按照由简到繁的顺序逐步发布的等。
本文主要内容：
- ProcessBar自定义标准样式；
- ProcessBar自定义环形进度样式；
二．ProcessBar标准样式
效果图：
ProcessBar的样式非常简单：
<!--ProgressBar Style-->
<Style TargetType="ProgressBar" x:Key="SimpleProgressBar">
<Setter Property="Background" Value="{StaticResource ControlBorderBrush}" />
<Setter Property="Maximum" Value="1" />
<Setter Property="Value" Value="0" />
<Setter Property="Height" Value="10" />
<Setter Property="IsTabStop" Value="False" />
<Setter Property="Foreground" Value="{StaticResource FocusBorderBrush}" />
<Setter Property="SnapsToDevicePixels" Value="True" />
<Setter Property="local:ControlAttachProperty.CornerRadius" Value="0" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ProgressBar">
<Grid x:Name="Root" >
<Border x:Name="PART_Track" Background="{TemplateBinding Background}"
CornerRadius="{TemplateBinding local:ControlAttachProperty.CornerRadius}"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
<Border x:Name="PART_Indicator" HorizontalAlignment="Left" Background="{TemplateBinding Foreground}"
CornerRadius="{TemplateBinding local:ControlAttachProperty.CornerRadius}"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="Orientation" Value="Vertical">
<Setter Property="LayoutTransform" TargetName="Root" >
<Setter.Value>
<RotateTransform Angle="-90" />
</Setter.Value>
</Setter>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
使用示例：
<ProgressBar Margin="5" Value="{Binding Percent,Mode=OneWay}" Style="{StaticResource SimpleProgressBar}" x:Name="pro4"></ProgressBar>
<ProgressBar Margin="5" Value="{Binding Percent,Mode=OneWay}" Height="15" x:Name="pro5" Background="LightSteelBlue" Foreground="OrangeRed"
Style="{StaticResource SimpleProgressBar}"></ProgressBar>
三．ProcessBar环形进度样式
效果图：
样式定义也比较简单：
<!--注意：该样式的ProgressBar的最大值为1，,BorderThickness控制环的大小-->
<!--ed需要引用：xmlns:ed="http://schemas.microsoft.com/expression/2010/drawing"--> <Style x:Key="LoopProcessBar" TargetType="{x:Type ProgressBar}">
<Setter Property="Background" Value="#C1D1DE"/>
<Setter Property="Margin" Value="5"/>
<Setter Property="Width" Value="300"/>
<Setter Property="Height" Value="300"/>
<Setter Property="BorderBrush" Value="BlueViolet"/>
<Setter Property="BorderThickness" Value="60"/>
<Setter Property="Foreground" Value="{StaticResource TextForeground}"/>
<Setter Property="Maximum" Value="1"/>
<Setter Property="Minimum" Value="0"/>
<Setter Property="Value" Value="0"/>
<Setter Property="IsTabStop" Value="False"/>
<Setter Property="IsHitTestVisible" Value="False"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ProgressBar}">
<Viewbox Stretch="Uniform" VerticalAlignment="Center" HorizontalAlignment="Center">
<Grid Margin="{TemplateBinding Margin}" SnapsToDevicePixels="True" Width="{TemplateBinding Width}" Height="{TemplateBinding Height}" >
<!--背景环-->
<ed:Arc Margin="{TemplateBinding Margin}" Opacity="0.6" ArcThickness="{Binding Path=BorderThickness,RelativeSource={RelativeSource TemplatedParent},Mode=OneWay,Converter={x:Static local:XConverter.ThicknessToDoubleConverter}}"
StartAngle="0" Fill="{TemplateBinding Background}" EndAngle="360" Stretch="None" x:Name="arcOuter" />
<!--值-环-->
<ed:Arc Margin="{TemplateBinding Margin}" x:Name="arcValue" ArcThickness="{Binding Path=BorderThickness,RelativeSource={RelativeSource TemplatedParent},Mode=OneWay,Converter={x:Static local:XConverter.ThicknessToDoubleConverter}}"
StartAngle="0" Fill="{TemplateBinding BorderBrush}"
Stretch="None" Panel.ZIndex="2"
EndAngle="{TemplateBinding Value, Converter={x:Static local:XConverter.PercentToAngleConverter}}" >
</ed:Arc>
</Grid>
</Viewbox>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
上面样式中使用了两个转换器：
- ThicknessToDoubleConverter：使用ProcessBar本身的属性BorderThickness设置环形宽度，把BorderThickness转换为环Arc宽度所需要的值；
- PercentToAngleConverter：当前进度值转换为环Arc的角度值；
这个地方有个小技巧，把常用的转换器声明为静态变量，XAML中以"x:Static"方式静态使用，这样使用的时候就方便多了，不用xaml中单独定义了。当然这样做也有弊端，因为静态变量本身的特点所决定的，不可滥用。
/// <summary>
/// 百分比转换为角度值
/// </summary>
public class PercentToAngleConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
var percent = value.ToSafeString().ToDouble();
if (percent >= ) return 360.0D;
return percent * ;
} public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
throw new NotImplementedException();
}
} /// <summary>
/// 获取Thickness固定值double
/// </summary>
public class ThicknessToDoubleConverter : IValueConverter
{
public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
{
var thickness = (Thickness)value;
return thickness.Left;
} public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
{
return DependencyProperty.UnsetValue;
}
}
使用示例：
<ProgressBar Style="{StaticResource LoopProcessBar}" Value="{Binding Percent,Mode=OneWay}" x:Name="pro1" ></ProgressBar>
<Grid Width="200" Height="200">
<ProgressBar Style="{StaticResource LoopProcessBar}" Value="{Binding Percent,Mode=OneWay}" x:Name="pro2" Margin="0" Width="200" Height="200" BorderThickness="20" BorderBrush="#EF436F"/>
<TextBlock FontSize="30" Text="{Binding Value,Mode=OneWay,ElementName=pro2,StringFormat={}{0:p1}}" VerticalAlignment="Center" HorizontalAlignment="Center"/>
</Grid>
<ProgressBar Style="{StaticResource LoopProcessBar}" x:Name="pro3" Value="{Binding Percent,Mode=OneWay}" Width="100" Height="100" BorderThickness="10" BorderBrush="#EFBF0E"></ProgressBar>