C# WPF侧边栏导航菜单（Dropdown Menu）

沙漠尽头的狼

.NET工程师，网站:https://dotnet9.com

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本文 Dotnet9 https:// dotnet9.com 已收录，站长乐于分享dotnet相关技术，比如Winform、WPF、 http:// ASP.NET Core等，亦有C++桌面相关的Qt Quick和Qt Widgets等，只分享自己熟悉的、自己会的。

阅读导航：

一、先看效果
二、本文背景
三、代码实现
四、文章参考
五、代码下载

一、先看效果

二、本文背景
YouTube Design com WPF 大神处习得，菜单导航功能实现，常规的管理系统应该常用，左侧显示菜单条目，点击菜单，右侧切换不同的业务用户控件。
常用菜单可以采用TreeView树形控件+特定样式实现，本文介绍的是使用Expander+ListView的组合形式实现的导航菜单，两种各有各的好处，本文不做优劣评价。

三、代码实现
3.1 添加Nuget库
站长使用.Net Core 3.1创建的WPF工程，创建“DropDownMenu”解决方案后，需要添加两个Nuget库：MaterialDesignThemes和MaterialDesignColors，上图的效果是使用该控件库实现的，非常强大。

3.2 工程结构

文件说明：

App.xaml：只引入MD控件样式。
MainWindow.展示导航菜单及控制菜单对应的用户控件切换。
UserControlMenuItem为单个菜单用户控件，由 Expander+ListView的组合形式实现。
UserControlCustomers和UserControlProviders作为两个举例用的业务用户控件。
ViewModel中定义的两个菜单相关的类，将菜单及业务用户控件关联。

3.3 App.xaml引入MD控件样式

<Application x:Class="DropDownMenu.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:local="clr-namespace:DropDownMenu"
             StartupUri="MainWindow.xaml">
    <Application.Resources>
        <ResourceDictionary>
            <ResourceDictionary.MergedDictionaries>
                <ResourceDictionary Source="pack://application:,,,/MaterialDesignThemes.Wpf;component/Themes/MaterialDesignTheme.Light.xaml"/>
                <ResourceDictionary Source="pack://application:,,,/MaterialDesignThemes.Wpf;component/Themes/MaterialDesignTheme.Defaults.xaml"/>
                <ResourceDictionary Source="pack://application:,,,/MaterialDesignColors;component/Themes/Recommended/Primary/MaterialDesignColor.Blue.xaml"/>
                <ResourceDictionary Source="pack://application:,,,/MaterialDesignColors;component/Themes/Recommended/Accent/MaterialDesignColor.Indigo.xaml"/>
            </ResourceDictionary.MergedDictionaries>
        </ResourceDictionary>
    </Application.Resources>
</Application>

3.4 主窗体
MainWindow.xaml，整体布局，看上图加上下面的界面代码，添加界面左上角logo图标、左侧导航菜单、右侧业务控件显示容器等。

<Window x:Class="DropDownMenu.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:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:DropDownMenu"
        xmlns:materialDesign="http://materialdesigninxaml.net/winfx/xaml/themes"
        mc:Ignorable="d"
        Title="下拉菜单" Height="450" Width="800" WindowStartupLocation="CenterScreen" WindowState="Maximized">
        <Grid.RowDefinitions>
            <RowDefinition Height="Auto"/>
            <RowDefinition Height="*"/>
        </Grid.RowDefinitions>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="250"/>
            <ColumnDefinition Width="*"/>
        </Grid.ColumnDefinitions>
        <materialDesign:ColorZone Mode="PrimaryMid" Grid.ColumnSpan="2" HorizontalAlignment="Stretch">
                <materialDesign:PopupBox PlacementMode="BottomAndAlignRightEdges" HorizontalAlignment="Right" Margin="10"/>
            </Grid>
        </materialDesign:ColorZone>
        <Grid HorizontalAlignment="Stretch" Grid.Row="1" Background="{StaticResource PrimaryHueMidBrush}">
            <Grid.RowDefinitions>
                <RowDefinition Height="70"/>
                <RowDefinition Height="326*"/>
            </Grid.RowDefinitions>
            <Grid Grid.Row="0" Background="GhostWhite">
                <Image Source="https://img.dotnet9.com/logo.png"/>
            </Grid>
            <ScrollViewer HorizontalAlignment="Stretch" HorizontalScrollBarVisibility="Disabled" VerticalScrollBarVisibility="Auto" Grid.Row="1">
                <StackPanel x:Name="Menu" Margin="10"/>
            </ScrollViewer>
        </Grid>
        <StackPanel x:Name="StackPanelMain" Grid.Row="1" Grid.Column="1" HorizontalAlignment="Stretch">
        </StackPanel>
    </Grid>
</Window>

MainWindow.xaml.cs，主窗体后台代码，没啥好说的，初始化菜单绑定数据、切换菜单显示用户控件。

using DropDownMenu.ViewModel;
using MaterialDesignThemes.Wpf;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
namespace DropDownMenu
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
        public MainWindow()
            InitializeComponent();
            var menuRegister = new List<SubItem>();
            menuRegister.Add(new SubItem("客户", new UserControlCustomers()));
            menuRegister.Add(new SubItem("供应商", new UserControlProviders()));
            menuRegister.Add(new SubItem("员工"));
            menuRegister.Add(new SubItem("产品"));
            var item6 = new ItemMenu("登记", menuRegister, PackIconKind.Register);
            var menuSchedule = new List<SubItem>();
            menuSchedule.Add(new SubItem("服务"));
            menuSchedule.Add(new SubItem("会议"));
            var item1 = new ItemMenu("预约", menuSchedule, PackIconKind.Schedule);
            var menuReports = new List<SubItem>();
            menuReports.Add(new SubItem("客户"));
            menuReports.Add(new SubItem("供应商"));
            menuReports.Add(new SubItem("产品"));
            menuReports.Add(new SubItem("库存"));
            menuReports.Add(new SubItem("销售额"));
            var item2 = new ItemMenu("报告", menuReports, PackIconKind.FileReport);
            var menuExpenses = new List<SubItem>();
            menuExpenses.Add(new SubItem("固定资产"));
            menuExpenses.Add(new SubItem("流动资金"));
            var item3 = new ItemMenu("费用", menuExpenses, PackIconKind.ShoppingBasket);
            var menuFinancial = new List<SubItem>();
            menuFinancial.Add(new SubItem("现金流"));
            var item4 = new ItemMenu("财务", menuFinancial, PackIconKind.ScaleBalance);
            Menu.Children.Add(new UserControlMenuItem(item6, this));
            Menu.Children.Add(new UserControlMenuItem(item1, this));
            Menu.Children.Add(new UserControlMenuItem(item2, this));
            Menu.Children.Add(new UserControlMenuItem(item3, this));
            Menu.Children.Add(new UserControlMenuItem(item4, this));
        internal void SwitchScreen(object sender)
            var screen = ((UserControl)sender);
            if (screen != null)
                StackPanelMain.Children.Clear();
                StackPanelMain.Children.Add(screen);
}

3.5 导航子菜单用户控件
UserControlMenuItem.xaml

<UserControl x:Class="DropDownMenu.UserControlMenuItem"
             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:DropDownMenu"             
             xmlns:materialDesign="http://materialdesigninxaml.net/winfx/xaml/themes"
             mc:Ignorable="d">
        <materialDesign:PackIcon Kind="{Binding Icon}" Width="15" Height="15" Margin="10 16" Foreground="White"/>
        <ListBoxItem x:Name="ListViewItemMenu" Content="{Binding Header}" Padding="37 14" FontSize="15" Foreground="White"/>
        <Expander x:Name="ExpanderMenu" Header="{Binding Header}" IsExpanded="False" Width="210" HorizontalAlignment="Right" Background="{x:Null}" Foreground="White">
            <ListView x:Name="ListViewMenu" ItemsSource="{Binding SubItems}" Foreground="White" ScrollViewer.HorizontalScrollBarVisibility="Disabled" SelectionChanged="ListViewMenu_SelectionChanged">
                <ListView.ItemTemplate>
                    <DataTemplate>
                        <TextBlock Text="{Binding Name}" Padding="20 5"/>
                    </DataTemplate>
                </ListView.ItemTemplate>
            </ListView>
        </Expander>
    </Grid>
</UserControl>

UserControlMenuItem.xaml.cs

using DropDownMenu.ViewModel;
using System;
using System.Collections.Generic;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
namespace DropDownMenu
    /// <summary>
    /// UserControlMenuItem.xaml 的交互逻辑
    /// </summary>
    public partial class UserControlMenuItem : UserControl
        MainWindow _context;
        public UserControlMenuItem(ItemMenu itemMenu, MainWindow context)
            InitializeComponent();
            _context = context;
            ExpanderMenu.Visibility = itemMenu.SubItems == null ? Visibility.Collapsed : Visibility.Visible;
            ListViewItemMenu.Visibility = itemMenu.SubItems == null ? Visibility.Visible : Visibility.Collapsed;
            this.DataContext = itemMenu;
        private void ListViewMenu_SelectionChanged(object sender, SelectionChangedEventArgs e)
            _context.SwitchScreen(((SubItem)((ListView)sender).SelectedItem).Screen);

3.6 菜单ViewModel类
ItemMenu.cs

using MaterialDesignThemes.Wpf;
using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Controls;
namespace DropDownMenu.ViewModel
    public class ItemMenu
        public ItemMenu(string header, List<SubItem> subItems, PackIconKind icon)
            Header = header;
            SubItems = subItems;
            Icon = icon;
        public string Header { get; private set; }
        public PackIconKind Icon { get; private set; }
        public List<SubItem> SubItems { get; private set; }
        public UserControl Screen { get; private set; }

SubItem.cs

using System;
using System.Collections.Generic;
using System.Text;
using System.Windows.Controls;
namespace DropDownMenu.ViewModel
    public class SubItem
        public SubItem(string name, UserControl screen = null)
            Name = name;
            Screen = screen;
        public string Name { get; private set; }
        public UserControl Screen { get; private set; }
}

3.7 两个举例用的用户控件
UserControlCustomers.xaml

<UserControl x:Class="DropDownMenu.UserControlCustomers"
             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:DropDownMenu"
             mc:Ignorable="d" 
             d:DesignHeight="450" d:DesignWidth="800">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="*"/>
            <ColumnDefinition Width="*"/>
            <ColumnDefinition Width="*"/>
            <ColumnDefinition Width="*"/>
        </Grid.ColumnDefinitions>
        <Grid.RowDefinitions>
            <RowDefinition Height="150"/>
            <RowDefinition Height="*"/>
        </Grid.RowDefinitions>
        <Border Margin="5" Grid.Column="0" Background="#FFC5C5C5" VerticalAlignment="Stretch" CornerRadius="12"/>
        <Border Margin="5" Grid.Column="1" Background="#FF7C54A0" VerticalAlignment="Stretch" CornerRadius="12"/>
        <Border Margin="5" Grid.Column="2" Background="#FF83CD80" VerticalAlignment="Stretch" CornerRadius="12"/>
        <Border Margin="5" Grid.Column="3" Background="#FFEE9246" VerticalAlignment="Stretch" CornerRadius="12"/>
    </Grid>
</UserControl>

UserControlProviders.xaml

<UserControl x:Class="DropDownMenu.UserControlProviders"
             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:DropDownMenu"
             mc:Ignorable="d" 
             d:DesignHeight="450" d:DesignWidth="800">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="*"/>
            <ColumnDefinition Width="*"/>
            <ColumnDefinition Width="*"/>
            <ColumnDefinition Width="*"/>
        </Grid.ColumnDefinitions>
        <Grid.RowDefinitions>
            <RowDefinition Height="150"/>
            <RowDefinition Height="*"/>
        </Grid.RowDefinitions>