简介

Microsoft官网关于 WindowChome 的介绍

截取Microsoft文章的一段话：
  若要在保留其标准功能时自定义窗口，可以使用该 WindowChrome 类。 该 WindowChrome 类将窗口框架的功能与视觉对象分开，并允许你控制应用程序窗口的客户端和非客户端区域之间的边界。 通过 WindowChrome 该类，可以通过扩展工作区来覆盖非工作区，将 WPF 内容置于窗口框架中。 同时，它通过两个不可见区域保留系统行为： 调整边框 和 标题 区域的大小。

效果图

自定义最小化、最大化、关闭按钮

• 最小化按钮

<Stylex:Key="SystemCloseButtonStyle"BasedOn="{StaticResource SystemButtonStyleBase}"TargetType="{x:Type Button}"><Setter Property="Template"><Setter.Value><ControlTemplate TargetType="{x:Type Button}"><Grid Background="{TemplateBinding Background}"><Viewbox Width="12" Height="12"><Path Data="M550.848 502.496l308.64-308.896a31.968 31.968 0 1 0-45.248-45.248l-308.608 308.896-308.64-308.928a31.968 31.968 0 1 0-45.248 45.248l308.64 308.896-308.64 308.896a31.968 31.968 0 1 0 45.248 45.248l308.64-308.896 308.608 308.896a31.968 31.968 0 1 0 45.248-45.248l-308.64-308.864z" Fill="{TemplateBinding BorderBrush}" /></Viewbox><ContentPresenterHorizontalAlignment="Center"VerticalAlignment="Center"Content="{TemplateBinding Content}" /></Grid><ControlTemplate.Triggers><Trigger Property="IsMouseOver" Value="True"><Setter Property="Background" Value="{StaticResource CloseColor}" /><Setter Property="BorderBrush" Value="{StaticResource DominantColor}" /></Trigger><Trigger Property="IsFocused" Value="True"><Setter Property="FocusVisualStyle" Value="{x:Null}" /></Trigger></ControlTemplate.Triggers></ControlTemplate></Setter.Value></Setter>
</Style>

• 最大化按钮

<Stylex:Key="SystemMaxButtonStyle"BasedOn="{StaticResource SystemButtonStyleBase}"TargetType="{x:Type Button}"><Setter Property="Template"><Setter.Value><ControlTemplate TargetType="{x:Type Button}"><Grid Background="{TemplateBinding Background}"><Viewbox Width="12" Height="12"><Path Data="M959.72 0H294.216a63.96 63.96 0 0 0-63.96 63.96v127.92H64.28A63.96 63.96 0 0 0 0.32 255.84V959.4a63.96 63.96 0 0 0 63.96 63.96h703.56a63.96 63.96 0 0 0 63.96-63.96V792.465h127.92a63.96 63.96 0 0 0 63.96-63.96V63.96A63.96 63.96 0 0 0 959.72 0zM767.84 728.505V959.4H64.28V255.84h703.56z m189.322 0H831.8V255.84a63.96 63.96 0 0 0-63.96-63.96H294.216V63.96H959.72z" Fill="{TemplateBinding BorderBrush}" /></Viewbox><ContentPresenterHorizontalAlignment="Center"VerticalAlignment="Center"Content="{TemplateBinding Content}" /></Grid><ControlTemplate.Triggers><Trigger Property="IsMouseOver" Value="True"><Setter Property="Background" Value="{StaticResource SuspensionColor}" /></Trigger><Trigger Property="IsFocused" Value="True"><Setter Property="FocusVisualStyle" Value="{x:Null}" /></Trigger></ControlTemplate.Triggers></ControlTemplate></Setter.Value></Setter>
</Style>

• 关闭按钮

<Stylex:Key="SystemMinButtonStyle"BasedOn="{StaticResource SystemButtonStyleBase}"TargetType="{x:Type Button}"><Setter Property="Template"><Setter.Value><ControlTemplate TargetType="{x:Type Button}"><Grid Background="{TemplateBinding Background}"><Viewbox Width="12" Height="10"><Path Data="M928.2 548h-832c-17.7 0-32-14.3-32-32s14.3-32 32-32h832c17.7 0 32 14.3 32 32s-14.3 32-32 32z" Fill="{TemplateBinding BorderBrush}" /></Viewbox><ContentPresenterHorizontalAlignment="Center"VerticalAlignment="Center"Content="{TemplateBinding Content}" /></Grid><ControlTemplate.Triggers><Trigger Property="IsMouseOver" Value="True"><Setter Property="Background" Value="{StaticResource SuspensionColor}" /></Trigger><Trigger Property="IsFocused" Value="True"><Setter Property="FocusVisualStyle" Value="{x:Null}" /></Trigger></ControlTemplate.Triggers></ControlTemplate></Setter.Value></Setter>
</Style>

/// <summary>
/// 窗口移动
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void Move_Click(object sender, System.Windows.Input.MouseButtonEventArgs e) => this.DragMove();/// <summary>
/// 最小化
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void BtnMin_Click(object sender, RoutedEventArgs e) => WindowState = WindowState.Minimized;/// <summary>
/// 最大化/还原
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void BtnMax_Click(object sender, RoutedEventArgs e) => WindowState = WindowState is WindowState.Normal ? WindowState.Maximized : WindowState.Normal;/// <summary>
/// 关闭
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void BtnClose_Click(object sender, RoutedEventArgs e) => Application.Current.Shutdown();

布局实现

首先我们需要在 MainWindow 也就是我们的主窗口中的 Window.Resources 中实现 WindowChrome 的基本样式：
WindowChrome.ResizeBorderThickness 设置不可见边框宽度
WindowChrome.CaptionHeight> 设置属于标题栏的范围——高度
WindowChrome.UseAeroCaptionButtons 是否启用默认系统按钮功能——三大金刚键
WindowChrome.NonClientFrameEdges 设置客户区域，使用 bottom 可以实现加载时空白窗口而不显示默认窗口，提升用户体验

<Windowx:Class="SignalRClient.MainWindow"xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"xmlns:d="http://schemas.microsoft.com/expression/blend/2008"xmlns:local="clr-namespace:SignalRClient"xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"Title=""Width="880"Height="620"MinWidth="700"MinHeight="500"Style="{StaticResource mainWindow}"WindowChrome.WindowChrome="{DynamicResource WindowChromeKey}"WindowStartupLocation="CenterScreen"mc:Ignorable="d"><Window.Resources><WindowChrome x:Key="WindowChromeKey"><WindowChrome.ResizeBorderThickness><Thickness>5</Thickness></WindowChrome.ResizeBorderThickness><WindowChrome.CaptionHeight>60</WindowChrome.CaptionHeight><WindowChrome.UseAeroCaptionButtons>false</WindowChrome.UseAeroCaptionButtons><WindowChrome.NonClientFrameEdges>bottom</WindowChrome.NonClientFrameEdges></WindowChrome></Window.Resources>
</Window>

重写窗口，实现最大化窗口下，标题栏及客户区域偏移问题的修正。
通过代码获取当前窗口的工作区域，及任务栏以外的其他区域
System.Windows.SystemParameters.WorkArea.Width 获取工作区域的宽
System.Windows.SystemParameters.WorkArea.Height 获取工作区域的高
为什么要使用 ValueConverter 主要是因为 WorkArea 返回的类型无法直接 binding xaml

<ValueConverters:WorkAreaWidth x:Key="workAreaWidth" />
<ValueConverters:WorkAreaHeight x:Key="workAreaHeight" /><Style x:Key="mainWindow" TargetType="{x:Type Window}"><Setter Property="Template"><Setter.Value><ControlTemplate TargetType="Window"><ContentControl x:Name="window" Content="{TemplateBinding Content}" /><ControlTemplate.Triggers><Trigger Property="WindowState" Value="Maximized"><Setter TargetName="window" Property="MaxHeight" Value="{Binding Converter={StaticResource workAreaHeight}}" /><Setter TargetName="window" Property="MaxWidth" Value="{Binding Converter={StaticResource workAreaWidth}}" /></Trigger></ControlTemplate.Triggers></ControlTemplate></Setter.Value></Setter>
</Style>

using System;
using System.Globalization;
using System.Windows.Data;namespace SignalRClient.ValueConverters
{internal class WorkAreaWidth : IValueConverter{public object Convert(object value, Type targetType, object parameter, CultureInfo culture){return System.Windows.SystemParameters.WorkArea.Width;}public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture){throw new NotImplementedException();}}
}

using System;
using System.Globalization;
using System.Windows.Data;namespace SignalRClient.ValueConverters
{internal class WorkAreaHeight : IValueConverter{public object Convert(object value, Type targetType, object parameter, CultureInfo culture){return System.Windows.SystemParameters.WorkArea.Height;}public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture){throw new NotImplementedException();}}
}

结语

一开始，确实很难搞，Microsoft 的文档，里面也并没有，详细介绍窗口内容溢出的问题，但是只要仔细研究过 WPF 的同学都知道，很多东西是可以通过 Trigger 来实现的。Get 到这一点很多问题就迎刃而解了。欢迎大家留言通过探讨 😃😃😃