WPF 自定义ComboBox样式，自定义多选控件

一、ComboBox基本样式

ComboBox有两种状态，可编辑和不可编辑状态。通过设置IsEditable属性可以切换控件状态。

先看基本样式效果：

基本样式代码如下：

        
        <SolidColorBrush x:Key="ComboBoxSelectdBackground" Color="#ff8c69"/>
        
        <SolidColorBrush x:Key="ComboBoxMouseOverBackground" Color="#ff3030"/>
        
        <SolidColorBrush x:Key="ComboBoxSelectedForeground" Color="White"/>
        
        <SolidColorBrush x:Key="ComboBoxMouseOverForegrond" Color="White"/>
        <Style TargetType="{x:Type ComboBox}">
            <Setter Property="ItemContainerStyle">
                <Setter.Value>
                    <Style TargetType="ComboBoxItem">
                        <Setter Property="Height" Value="20"/>
                        <Setter Property="Template">
                            <Setter.Value>
                                <ControlTemplate  TargetType="{x:Type ComboBoxItem}">
                                    <Grid Height="{TemplateBinding Height}" Width="{TemplateBinding Width}">
                                        <Border x:Name="_borderbg" Background="Transparent"/>
                                        <TextBlock Margin="3 0 3 0" VerticalAlignment="Center" x:Name="_txt" Foreground="#333" Text="{Binding Content,RelativeSource={RelativeSource TemplatedParent}}"/>
                                        <Border x:Name="_border" Background="White" Opacity="0"/>
                                    Grid>
                                    <ControlTemplate.Triggers>
                                        <Trigger Property="IsSelected" Value="true">
                                            <Setter TargetName="_borderbg" Property="Background" Value="{StaticResource ComboBoxSelectdBackground}" />
                                            <Setter TargetName="_txt" Property="Foreground" Value="{StaticResource ComboBoxSelectedForeground}"/>
                                        Trigger>
                                        <MultiTrigger>
                                            <MultiTrigger.Conditions>
                                                <Condition Property="IsSelected" Value="false"/>
                                                <Condition Property="IsMouseOver" Value="true"/>
                                            MultiTrigger.Conditions>
                                            <Setter TargetName="_borderbg" Property="Background" Value="{StaticResource ComboBoxMouseOverBackground}" />
                                            <Setter TargetName="_txt" Property="Foreground" Value="{StaticResource ComboBoxMouseOverForegrond}"/>
                                        MultiTrigger>

                                    ControlTemplate.Triggers>
                                ControlTemplate>
                            Setter.Value>
                        Setter>
                    Style>
                Setter.Value>
            Setter>
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="{x:Type ComboBox}">
                        <Grid>

                            <Grid.ColumnDefinitions>
                                <ColumnDefinition Width="0.7*"/>
                                <ColumnDefinition Width="0.3*" MaxWidth="30"/>
                            Grid.ColumnDefinitions>
                            <Border  Grid.Column="0" Grid.ColumnSpan="2" BorderThickness="1" BorderBrush="{TemplateBinding BorderBrush}" CornerRadius="1,0,0,1"/>
                            <ContentPresenter HorizontalAlignment="Left" Margin="3,3,0,3" x:Name="ContentSite" VerticalAlignment="Center" Content="{TemplateBinding SelectionBoxItem}" ContentTemplate="{TemplateBinding SelectionBoxItemTemplate}" ContentTemplateSelector="{TemplateBinding ItemTemplateSelector}" IsHitTestVisible="False"/>

                            
                            <ToggleButton Grid.Column="0"  Grid.ColumnSpan="2"  Template="{StaticResource ComboBoxToggleButton}" x:Name="ToggleButton" Focusable="false" IsChecked="{Binding Path=IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" ClickMode="Press"/>
                            
                            <TextBox   Visibility="Hidden" BorderThickness="0"   Margin="2 0 0 0" x:Name="PART_EditableTextBox"  VerticalAlignment="Center" Focusable="True" Background="Transparent" IsReadOnly="{TemplateBinding IsReadOnly}"/>

                            
                            <Popup IsOpen="{TemplateBinding IsDropDownOpen}" Placement="Bottom" x:Name="Popup" Focusable="False" AllowsTransparency="True" PopupAnimation="Slide">
                                <Grid MaxHeight="150" MinWidth="{TemplateBinding ActualWidth}" x:Name="DropDown" SnapsToDevicePixels="True">
                                    <Border x:Name="DropDownBorder"  BorderBrush="#e8e8e8" BorderThickness="1 0 1 1"/>
                                    <ScrollViewer Margin="1"  SnapsToDevicePixels="True" HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Auto" CanContentScroll="True">
                                        
                                        <StackPanel IsItemsHost="True" KeyboardNavigation.DirectionalNavigation="Contained" Background="White"/>
                                    ScrollViewer>
                                Grid>
                            Popup>
                        Grid>
                        <ControlTemplate.Triggers>
                            <Trigger Property="IsEditable" Value="true">
                                <Setter TargetName="PART_EditableTextBox" Property="Visibility" Value="Visible" />
                            Trigger>
                        ControlTemplate.Triggers>
                    ControlTemplate>
                Setter.Value>
            Setter>
        Style>

引用示例：

 <ComboBox x:Name="combobox"  Width="150" Margin="10" IsEditable="False" BorderBrush="#e8e8e8">
          <CheckBox Content="上海" Tag="1">CheckBox>
          <CheckBox Content="北京" Tag="2">CheckBox>
          <CheckBox Content="天津" Tag="3">CheckBox>
          <CheckBox Content="广州" Tag="4">CheckBox>
ComboBox>

二、ComboBox扩展样式（多选控件）

ComBoBox能够单选选择数据，那么能不能实现多选的操作呢，答案是肯定的。这里多选的自定义控件参考了博主“梦里花落知多少”的内容。我对样式做了补充，使其能够更方便的进行移除多选的内容。同时也更好的展示了已选的内容，大家可以根据实际需求做出更好的展示效果。

先看效果：

2.1、添加自定义控件MultiComboBox

 public class MultiComboBox : ComboBox
    {
        static MultiComboBox()
        {
            DefaultStyleKeyProperty.OverrideMetadata(typeof(MultiComboBox), new FrameworkPropertyMetadata(typeof(MultiComboBox)));
        }


        private static void OnPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            d.SetValue(e.Property, e.NewValue);
        }



        /// 

        /// 选中项列表
        /// 
        public ObservableCollection ChekedItems
        {
            get { return (ObservableCollection)GetValue(ChekedItemsProperty); }
            set { SetValue(ChekedItemsProperty, value); }
        }

        public static readonly DependencyProperty ChekedItemsProperty =
            DependencyProperty.Register("ChekedItems", typeof(ObservableCollection), typeof(MultiComboBox), new PropertyMetadata(new ObservableCollection(), OnPropertyChanged));



        /// 

        /// ListBox竖向列表
        /// 
        private ListBox _ListBoxV;

        /// 

        /// ListBox横向列表
        /// 
        private ListBox _ListBoxH;

        public override void OnApplyTemplate()
        {
            base.OnApplyTemplate();
            _ListBoxV = Template.FindName("PART_ListBox", this) as ListBox;
            _ListBoxH = Template.FindName("PART_ListBoxChk", this) as ListBox;
            _ListBoxH.ItemsSource = ChekedItems;
            _ListBoxV.SelectionChanged += _ListBoxV_SelectionChanged;
            _ListBoxH.SelectionChanged += _ListBoxH_SelectionChanged;

            if (ItemsSource != null)
            {
                foreach (var item in ItemsSource)
                {
                    MultiCbxBaseData bdc = item as MultiCbxBaseData;
                    if (bdc.IsCheck)
                    {
                        _ListBoxV.SelectedItems.Add(bdc);
                    }
                }
            }
        }

        private void _ListBoxH_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            foreach (var item in e.RemovedItems)
            {
                MultiCbxBaseData datachk = item as MultiCbxBaseData;

                for (int i = 0; i < _ListBoxV.SelectedItems.Count; i++)
                {
                    MultiCbxBaseData datachklist = _ListBoxV.SelectedItems[i] as MultiCbxBaseData;
                    if (datachklist.ID == datachk.ID)
                    {
                        _ListBoxV.SelectedItems.Remove(_ListBoxV.SelectedItems[i]);
                    }
                }
            }
        }

        void _ListBoxV_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            foreach (var item in e.AddedItems)
            {
                MultiCbxBaseData datachk = item as MultiCbxBaseData;
                datachk.IsCheck = true;
                if (ChekedItems.IndexOf(datachk) < 0)
                {
                    ChekedItems.Add(datachk);
                }
            }

            foreach (var item in e.RemovedItems)
            {
                MultiCbxBaseData datachk = item as MultiCbxBaseData;
                datachk.IsCheck = false;
                ChekedItems.Remove(datachk);
            }
        }

        public class MultiCbxBaseData
        {
            private int _id;
            /// 

            /// 关联主键
            /// 
            public int ID
            {
                get { return _id; }
                set { _id = value; }
            }

            private string _viewName;
            /// 

            /// 显示名称
            /// 
            public string ViewName
            {
                get { return _viewName; }
                set
                {
                    _viewName = value;
                }
            }

            private bool _isCheck;
            /// 

            /// 是否选中
            /// 
            public bool IsCheck
            {
                get { return _isCheck; }
                set { _isCheck = value;}
            }
        }
    }

2.2、定义MultiComboBox控件的样式

 <ControlTemplate x:Key="ComboBoxToggleButton" TargetType="{x:Type ToggleButton}">
        <Grid Height="25">
            <Border Grid.Column="1" Background="White" Opacity="0"   Cursor="Hand"/>
            <Path x:Name="Arrow" Grid.Column="1"   Data="M 0 0  6 6 12 0 Z"  VerticalAlignment="Center" HorizontalAlignment="Center" Stretch="None" Fill="#B1B1B1" />
        Grid>
        <ControlTemplate.Triggers>
            <Trigger Property="IsChecked" Value="true">
                <Setter TargetName="Arrow" Property="RenderTransform">
                    <Setter.Value>
                        <RotateTransform   CenterX="6" CenterY="3" Angle="180">RotateTransform>
                    Setter.Value>
                Setter>
                <Setter TargetName="Arrow" Property="Margin" Value="0 0 0 2"/>
            Trigger>
        ControlTemplate.Triggers>
    ControlTemplate>

    
    <Style  TargetType="{x:Type local:MultiComboBox}">
        <Setter Property="Width" Value="200" />
        <Setter Property="HorizontalContentAlignment" Value="Stretch" />
        <Setter Property="VerticalContentAlignment" Value="Center" />
        <Setter Property="SnapsToDevicePixels" Value="True" />
        <Setter Property="MaxDropDownHeight" Value="400" />
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type local:MultiComboBox}">
                    <Grid>
                        <Border x:Name="Bg" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"  Width="{TemplateBinding Width}" Height="{TemplateBinding Height}" BorderBrush="#eaeaea" BorderThickness="1"  >
                            <Grid x:Name="PART_Root">

                                <Grid x:Name="PART_InnerGrid" Margin="0">
                                    <Grid.ColumnDefinitions>
                                        <ColumnDefinition Width="*" />
                                        <ColumnDefinition Width="0.3*" MaxWidth="30" />
                                    Grid.ColumnDefinitions>
                                    <ListBox x:Name="PART_ListBoxChk"  SelectionMode="Multiple" BorderThickness="0" ScrollViewer.VerticalScrollBarVisibility="Disabled">
                                        <ListBox.ItemsPanel>
                                            <ItemsPanelTemplate>
                                                <VirtualizingStackPanel Orientation="Horizontal" VirtualizingStackPanel.IsVirtualizing="True" />
                                            ItemsPanelTemplate>
                                        ListBox.ItemsPanel>
                                        <ListBox.ItemContainerStyle>
                                            <Style TargetType="ListBoxItem">
                                                <Setter Property="BorderThickness" Value="0"/>
                                                <Setter Property="IsSelected" Value="True"/>
                                                <Setter Property="Template">
                                                    <Setter.Value>
                                                        <ControlTemplate TargetType="ListBoxItem">
                                                            <CheckBox BorderThickness="0"  VerticalAlignment="Center" HorizontalAlignment="Center"  Content="{Binding ViewName}" IsChecked="{Binding Path=IsSelected,RelativeSource={RelativeSource TemplatedParent},Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}"/>
                                                        ControlTemplate>
                                                    Setter.Value>
                                                Setter>
                                            Style>
                                        ListBox.ItemContainerStyle>
                                    ListBox>

                                    
                                    <ToggleButton x:Name="PART_DropDownToggle" IsTabStop="False"  
                                         IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}"
                                         Grid.Column="1" Template="{StaticResource ComboBoxToggleButton}" />
                                Grid>
                            Grid>
                        Border>
                        
                        <Popup x:Name="PART_Popup" AllowsTransparency="True"  Focusable="False" StaysOpen="False"
                               IsOpen="{Binding IsDropDownOpen, RelativeSource={RelativeSource TemplatedParent}}"
                               PopupAnimation="{DynamicResource {x:Static SystemParameters.ComboBoxPopupAnimationKey}}" Placement="Bottom">
                            <Grid Width="{Binding ActualWidth, RelativeSource={RelativeSource TemplatedParent}}"  MaxHeight="{Binding MaxDropDownHeight, RelativeSource={RelativeSource TemplatedParent}}" >
                                <ListBox x:Name="PART_ListBox" SelectionMode="Multiple" BorderThickness="1 0 1 1" Background="White" ItemsSource="{Binding ItemsSource,RelativeSource={RelativeSource TemplatedParent}}"
                                             MaxHeight="{TemplateBinding MaxDropDownHeight}" BorderBrush="#eaeaea"  >
                                    <ListBox.ItemContainerStyle>
                                        <Style  TargetType="ListBoxItem">
                                            <Setter Property="Template">
                                                <Setter.Value>
                                                    <ControlTemplate TargetType="{x:Type ListBoxItem}" >
                                                        <Grid  Height="22">
                                                            <Border x:Name="bg" BorderBrush="#eaeaea" BorderThickness="0"/>
                                                            <ContentPresenter x:Name="content"  />
                                                            <Border Background="White"  Opacity="0"/>
                                                        Grid>
                                                        <ControlTemplate.Triggers>
                                                            <Trigger Property="IsSelected" Value="True">
                                                                <Setter  TargetName="bg"  Property="Background" Value="#ADD6FF" />
                                                            Trigger>
                                                            <MultiTrigger>
                                                                <MultiTrigger.Conditions>
                                                                    <Condition Property="IsMouseOver" Value="true" />
                                                                    <Condition Property="IsSelected" Value="false"/>
                                                                MultiTrigger.Conditions>
                                                                <Setter TargetName="bg" Property="Background" Value="#009BDB" />
                                                                <Setter TargetName="bg" Property="Opacity" Value="0.7"/>
                                                                <Setter   Property="Foreground" Value="White" />
                                                            MultiTrigger>
                                                            <Trigger Property="IsEnabled" Value="False">
                                                                <Setter TargetName="bg" Property="Opacity" Value="0.3" />
                                                                <Setter   Property="Foreground" Value="Gray" />
                                                            Trigger>
                                                        ControlTemplate.Triggers>
                                                    ControlTemplate>
                                                Setter.Value>
                                            Setter>
                                        Style>
                                    ListBox.ItemContainerStyle>
                                    <ListBox.ItemTemplate>
                                        <DataTemplate>
                                            <Grid>
                                                <CheckBox x:Name="chk" Visibility="Hidden"  IsChecked="{Binding IsCheck,Mode=TwoWay}" VerticalAlignment="Center"/>
                                                <CheckBox VerticalAlignment="Center"  Foreground="{Binding Foreground,RelativeSource={RelativeSource AncestorType=ListBoxItem}}" IsChecked="{Binding  RelativeSource={RelativeSource AncestorType=ListBoxItem},Path=IsSelected,Mode=TwoWay}"  Content="{Binding Path=ViewName}" />
                                            Grid>
                                            <DataTemplate.Triggers>
                                                <DataTrigger   Binding="{Binding  RelativeSource={RelativeSource AncestorType=ListBoxItem},Path=IsSelected}" Value="true">
                                                    <Setter  TargetName="chk"  Property="IsChecked" Value="true"/>
                                                DataTrigger>
                                                <DataTrigger   Binding="{Binding  RelativeSource={RelativeSource AncestorType=ListBoxItem},Path=IsSelected}" Value="false">
                                                    <Setter     TargetName="chk" Property="IsChecked" Value="false"/>
                                                DataTrigger>
                                            DataTemplate.Triggers>
                                        DataTemplate>
                                    ListBox.ItemTemplate>
                                ListBox>
                            Grid>
                        Popup>
                    Grid>
                    
                ControlTemplate>
            Setter.Value>
        Setter>
    Style>

2.3、引用示例：

<local:MultiComboBox x:Name="multiCmb" Margin="10" Width="200"/>

2.4、后台代码（初始化绑定数据）：

  public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
            MultiComboBoxList = new ObservableCollection()
            {
                new MultiCbxBaseData(){
                    ID=0,
                    ViewName="张三",
                    IsCheck=false
                },
                new MultiCbxBaseData(){
                    ID=1,
                    ViewName="李四",
                    IsCheck=false
                },
                new MultiCbxBaseData(){
                    ID=2,
                    ViewName="王五",
                    IsCheck=false
                },
                new MultiCbxBaseData(){
                    ID=3,
                    ViewName="马六",
                    IsCheck=false
                },
                 new MultiCbxBaseData(){
                    ID=4,
                    ViewName="赵七",
                    IsCheck=false
                },
            };
            this.multiCmb.ItemsSource = MultiComboBoxList;
        }

        private ObservableCollection MultiComboBoxList;
    }

所有代码已经上传到github：https://github.com/cmfGit/WpfDemo.git