C# Listbox IsSynchronizedWithCurrentItem导致选择第一个项目，即使没有任何命令它这样做
我在wpf列表框中发现了一些可能是bug的东西。请看代码，然后我解释发生了什么 窗口C# Listbox IsSynchronizedWithCurrentItem导致选择第一个项目，即使没有任何命令它这样做,c#,wpf,xaml,combobox,listbox,C#,Wpf,Xaml,Combobox,Listbox,我在wpf列表框中发现了一些可能是bug的东西。请看代码，然后我解释发生了什么 窗口 <Window > <Grid> <local:MultiSelectionComboBox Width="200" MinHeight="25" HorizontalAlignment="Center"
<Window >
<Grid>
<local:MultiSelectionComboBox Width="200"
MinHeight="25"
HorizontalAlignment="Center"
VerticalAlignment="Center"
ASLDisplayMemberPath="FirstName"
ASLSelectedItems="{Binding SelectedModels}"
ItemsSource="{Binding Models}" />
<ListBox HorizontalAlignment="Right"
VerticalAlignment="Top"
DisplayMemberPath="FirstName"
ItemsSource="{Binding SelectedModels}" />
</Grid>
</Window>
<ComboBox>
<ComboBox.Style>
<Style TargetType="{x:Type ComboBox}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ComboBox}">
<Grid x:Name="MainGrid"
Width="Auto"
Height="Auto"
SnapsToDevicePixels="true">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="0" />
</Grid.ColumnDefinitions>
<Popup x:Name="PART_Popup"
Grid.ColumnSpan="2"
Margin="1"
AllowsTransparency="true"
IsOpen="{Binding Path=IsDropDownOpen,
RelativeSource={RelativeSource TemplatedParent}}"
Placement="Center"
PopupAnimation="{DynamicResource {x:Static SystemParameters.ComboBoxPopupAnimationKey}}">
<Border x:Name="DropDownBorder"
MinWidth="{Binding Path=ActualWidth,
ElementName=MainGrid}"
MaxHeight="{TemplateBinding MaxDropDownHeight}">
<ScrollViewer CanContentScroll="true">
<StackPanel>
<CheckBox x:Name="checkBox"
Command="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=ComboBox}, Path=CheckAllCommand}">select all</CheckBox>
<ListBox x:Name="lstBox"
here lies the problem without the line below I dont get to see the result on start up,
with the it selects the first item even if nothing is triggering it
IsSynchronizedWithCurrentItem="True"
ItemsSource="{TemplateBinding ItemsSource}"
KeyboardNavigation.DirectionalNavigation="Contained"
SelectionChanged="ListBoxOnSelectionChanged"
SelectionMode="Multiple"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" />
</StackPanel>
</ScrollViewer>
</Border>
</Popup>
<ToggleButton Grid.ColumnSpan="2"
MinWidth="20"
HorizontalAlignment="Right"
Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
IsChecked="{Binding Path=IsDropDownOpen,
Mode=TwoWay,
RelativeSource={RelativeSource TemplatedParent}}"
Style="{DynamicResource ToggleButtonStyle1}" />
<ItemsControl x:Name="itemsControl"
Margin="4,2,0,2"
ItemsSource="{Binding Path=SelectedItems,
ElementName=lstBox}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<WrapPanel IsItemsHost="True" Orientation="Horizontal" />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Border Margin="1"
HorizontalAlignment="Left"
VerticalAlignment="Top"
Background="#383838"
CornerRadius="2"
Padding="5,2,3,2">
<StackPanel Orientation="Horizontal">
<TextBlock x:Name="Test"
Foreground="White"
Loaded="Test_OnLoaded"
Text="{Binding RelativeSource={RelativeSource Mode=FindAncestor,
AncestorType={x:Type ComboBox}},
Path=ASLDisplayMemberPathActualValue}" />
<Button Width="12"
Height="12"
Margin="5,0,0,0"
Command="{Binding RelativeSource={RelativeSource Mode=FindAncestor,
AncestorType=ComboBox},
Path=UnselectCommand}"
CommandParameter="{Binding}">
<Button.Template>
<ControlTemplate TargetType="{x:Type Button}">
<Grid>
<Ellipse x:Name="PART_ButtonBackground"
Fill="White"
Opacity="0" />
<TextBlock x:Name="PART_Text"
Margin="0,0,0,1"
HorizontalAlignment="Center"
VerticalAlignment="Center"
FontSize="10"
Foreground="White"
Text="X" />
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter TargetName="PART_ButtonBackground" Property="Opacity" Value="0.8" />
<Setter TargetName="PART_Text" Property="Foreground" Value="Black" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Button.Template>
</Button>
</StackPanel>
</Border>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ComboBox.Style>
</ComboBox>
public partial class MultiSelectionComboBox : ComboBox
{
#region fields, dependencies, command and constructor
private ListBox listBox;
private ItemsControl itemsControl;
private CheckBox checkBox;
public static readonly DependencyProperty ASLSelectedItemsProperty = DependencyProperty.Register("ASLSelectedItems", typeof(ObservableCollection<object>), typeof(MultiSelectionComboBox), new PropertyMetadata(null));
public static readonly DependencyProperty ASLDisplayMemberPathProperty = DependencyProperty.Register("ASLDisplayMemberPath", typeof(string), typeof(MultiSelectionComboBox), new PropertyMetadata("Description"));
public MultiSelectionComboBox()
{
InitializeComponent();
}
public DelegateCommand<object> UnselectCommand { get; private set; }
public DelegateCommand CheckAllCommand { get; private set; }
public ObservableCollection<object> ASLSelectedItems
{
get { return (ObservableCollection<object>)GetValue(ASLSelectedItemsProperty); }
set { SetValue(ASLSelectedItemsProperty, value); }
}
public string ASLDisplayMemberPath
{
get { return (string)GetValue(ASLDisplayMemberPathProperty); }
set { SetValue(ASLDisplayMemberPathProperty, value); }
}
#endregion
private void CheckAll()
{
if (checkBox.IsChecked == true)
{
listBox.SelectAll();
}
else
{
listBox.UnselectAll();
}
}
private void GetControls()
{
checkBox = Template.FindName("checkBox", this) as CheckBox;
listBox = Template.FindName("lstBox", this) as ListBox;
itemsControl = Template.FindName("itemsControl", this) as ItemsControl;
}
private bool bug = true;
private void ListBoxOnSelectionChanged(object sender, SelectionChangedEventArgs e)
{
e.AddedItems.Cast<object>().Where(item => !ASLSelectedItems.Contains(item)).ForEach(p => ASLSelectedItems.Add(p));
e.RemovedItems.Cast<object>().Where(item => ASLSelectedItems.Contains(item)).ForEach(p => ASLSelectedItems.Remove(p));
checkBox.IsChecked = (listBox.ItemsSource as IList).Count == listBox.SelectedItems.Count;
}
public override void OnApplyTemplate()
{
base.OnApplyTemplate();
GetControls();
SetControls();
UnselectCommand = new DelegateCommand<object>(p => listBox?.SelectedItems.Remove(p));
CheckAllCommand = new DelegateCommand(CheckAll);
}
private void SetControls()
{
listBox.DisplayMemberPath = ASLDisplayMemberPath;
itemsControl.DisplayMemberPath = ASLDisplayMemberPath;
}
private void Test_OnLoaded(object sender, RoutedEventArgs e)
{
(sender as TextBlock)?.SetBinding(TextBlock.TextProperty, ASLDisplayMemberPath);
}
}
全选
<ComboBox>
<ComboBox.Style>
<Style TargetType="{x:Type ComboBox}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ComboBox}">
<Grid x:Name="MainGrid"
Width="Auto"
Height="Auto"
SnapsToDevicePixels="true">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="0" />
</Grid.ColumnDefinitions>
<Popup x:Name="PART_Popup"
Grid.ColumnSpan="2"
Margin="1"
AllowsTransparency="true"
IsOpen="{Binding Path=IsDropDownOpen,
RelativeSource={RelativeSource TemplatedParent}}"
Placement="Center"
PopupAnimation="{DynamicResource {x:Static SystemParameters.ComboBoxPopupAnimationKey}}">
<Border x:Name="DropDownBorder"
MinWidth="{Binding Path=ActualWidth,
ElementName=MainGrid}"
MaxHeight="{TemplateBinding MaxDropDownHeight}">
<ScrollViewer CanContentScroll="true">
<StackPanel>
<CheckBox x:Name="checkBox"
Command="{Binding RelativeSource={RelativeSource Mode=FindAncestor, AncestorType=ComboBox}, Path=CheckAllCommand}">select all</CheckBox>
<ListBox x:Name="lstBox"
here lies the problem without the line below I dont get to see the result on start up,
with the it selects the first item even if nothing is triggering it
IsSynchronizedWithCurrentItem="True"
ItemsSource="{TemplateBinding ItemsSource}"
KeyboardNavigation.DirectionalNavigation="Contained"
SelectionChanged="ListBoxOnSelectionChanged"
SelectionMode="Multiple"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" />
</StackPanel>
</ScrollViewer>
</Border>
</Popup>
<ToggleButton Grid.ColumnSpan="2"
MinWidth="20"
HorizontalAlignment="Right"
Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
IsChecked="{Binding Path=IsDropDownOpen,
Mode=TwoWay,
RelativeSource={RelativeSource TemplatedParent}}"
Style="{DynamicResource ToggleButtonStyle1}" />
<ItemsControl x:Name="itemsControl"
Margin="4,2,0,2"
ItemsSource="{Binding Path=SelectedItems,
ElementName=lstBox}">
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<WrapPanel IsItemsHost="True" Orientation="Horizontal" />
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Border Margin="1"
HorizontalAlignment="Left"
VerticalAlignment="Top"
Background="#383838"
CornerRadius="2"
Padding="5,2,3,2">
<StackPanel Orientation="Horizontal">
<TextBlock x:Name="Test"
Foreground="White"
Loaded="Test_OnLoaded"
Text="{Binding RelativeSource={RelativeSource Mode=FindAncestor,
AncestorType={x:Type ComboBox}},
Path=ASLDisplayMemberPathActualValue}" />
<Button Width="12"
Height="12"
Margin="5,0,0,0"
Command="{Binding RelativeSource={RelativeSource Mode=FindAncestor,
AncestorType=ComboBox},
Path=UnselectCommand}"
CommandParameter="{Binding}">
<Button.Template>
<ControlTemplate TargetType="{x:Type Button}">
<Grid>
<Ellipse x:Name="PART_ButtonBackground"
Fill="White"
Opacity="0" />
<TextBlock x:Name="PART_Text"
Margin="0,0,0,1"
HorizontalAlignment="Center"
VerticalAlignment="Center"
FontSize="10"
Foreground="White"
Text="X" />
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter TargetName="PART_ButtonBackground" Property="Opacity" Value="0.8" />
<Setter TargetName="PART_Text" Property="Foreground" Value="Black" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Button.Template>
</Button>
</StackPanel>
</Border>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ComboBox.Style>
</ComboBox>
public partial class MultiSelectionComboBox : ComboBox
{
#region fields, dependencies, command and constructor
private ListBox listBox;
private ItemsControl itemsControl;
private CheckBox checkBox;
public static readonly DependencyProperty ASLSelectedItemsProperty = DependencyProperty.Register("ASLSelectedItems", typeof(ObservableCollection<object>), typeof(MultiSelectionComboBox), new PropertyMetadata(null));
public static readonly DependencyProperty ASLDisplayMemberPathProperty = DependencyProperty.Register("ASLDisplayMemberPath", typeof(string), typeof(MultiSelectionComboBox), new PropertyMetadata("Description"));
public MultiSelectionComboBox()
{
InitializeComponent();
}
public DelegateCommand<object> UnselectCommand { get; private set; }
public DelegateCommand CheckAllCommand { get; private set; }
public ObservableCollection<object> ASLSelectedItems
{
get { return (ObservableCollection<object>)GetValue(ASLSelectedItemsProperty); }
set { SetValue(ASLSelectedItemsProperty, value); }
}
public string ASLDisplayMemberPath
{
get { return (string)GetValue(ASLDisplayMemberPathProperty); }
set { SetValue(ASLDisplayMemberPathProperty, value); }
}
#endregion
private void CheckAll()
{
if (checkBox.IsChecked == true)
{
listBox.SelectAll();
}
else
{
listBox.UnselectAll();
}
}
private void GetControls()
{
checkBox = Template.FindName("checkBox", this) as CheckBox;
listBox = Template.FindName("lstBox", this) as ListBox;
itemsControl = Template.FindName("itemsControl", this) as ItemsControl;
}
private bool bug = true;
private void ListBoxOnSelectionChanged(object sender, SelectionChangedEventArgs e)
{
e.AddedItems.Cast<object>().Where(item => !ASLSelectedItems.Contains(item)).ForEach(p => ASLSelectedItems.Add(p));
e.RemovedItems.Cast<object>().Where(item => ASLSelectedItems.Contains(item)).ForEach(p => ASLSelectedItems.Remove(p));
checkBox.IsChecked = (listBox.ItemsSource as IList).Count == listBox.SelectedItems.Count;
}
public override void OnApplyTemplate()
{
base.OnApplyTemplate();
GetControls();
SetControls();
UnselectCommand = new DelegateCommand<object>(p => listBox?.SelectedItems.Remove(p));
CheckAllCommand = new DelegateCommand(CheckAll);
}
private void SetControls()
{
listBox.DisplayMemberPath = ASLDisplayMemberPath;
itemsControl.DisplayMemberPath = ASLDisplayMemberPath;
}
private void Test_OnLoaded(object sender, RoutedEventArgs e)
{
(sender as TextBlock)?.SetBinding(TextBlock.TextProperty, ASLDisplayMemberPath);
}
}
公共部分类MultiSelectionComboBox:ComboBox
{
#区域字段、依赖项、命令和构造函数
私有列表框列表框；
私有项控件项控件；
私有复选框；
public static readonly dependencProperty ASLSelectedItemsProperty=dependencProperty.Register（“ASLSelectedItems”、typeof（ObservableCollection）、typeof（MultiSelectionComboBox）、new PropertyMetadata（null））；
公共静态只读DependencyProperty ASLDisplayMemberPathProperty=DependencyProperty.Register（“ASLDisplayMemberPath”、typeof（字符串）、typeof（多选组合框）、new PropertyMetadata（“说明”）；
公共多选组合框（）
{
初始化组件（）；
}
public DelegateCommand UnselectCommand{get；private set；}
public DelegateCommand CheckAllCommand{get；private set；}
公共可观测集合ASLSelectedItems
{
获取{return（observetecollection）GetValue（aslselecteditemsprroperty）；}
set{SetValue（ASLSelectedItemsProperty，value）；}
}
公共字符串ASLDisplayMemberPath
{
获取{return（string）GetValue（ASLDisplayMemberPathProperty）；}
set{SetValue（asldisplaymberpathProperty，value）；}
}
#端区
私有void CheckAll（）
{
如果（checkBox.IsChecked==true）
{
listBox.SelectAll（）；
}
其他的
{
listBox.UnselectAll（）；
}
}
私有控件（）
{
checkBox=Template.FindName（“checkBox”，this）作为复选框；
listBox=Template.FindName（“lstBox”，this）作为listBox；
itemsControl=Template.FindName（“itemsControl”，this）作为itemsControl；
}
私有布尔错误=真；
private void ListBoxOnSelectionChanged（对象发送者，选择ChangedEventArgs e）
{
e、 AddedItems.Cast（）.Where（item=>！ASLSelectedItems.Contains（item））.ForEach（p=>ASLSelectedItems.Add（p））；
e、 RemovedItems.Cast（）.Where（item=>ASLSelectedItems.Contains（item））.ForEach（p=>ASLSelectedItems.Remove（p））；
checkBox.IsChecked=（listBox.itemsource as IList）.Count==listBox.SelectedItems.Count；
}
应用程序模板（）上的公共重写无效
{
base.OnApplyTemplate（）；
GetControls（）；
SetControls（）；
UnselectCommand=newdelegateCommand（p=>listBox？.SelectedItems.Remove（p））；
CheckAllCommand=新的DelegateCommand（CheckAll）；
}
私有void SetControls（）
{
listBox.DisplayMemberPath=ASLDisplayMemberPath；
itemsControl.DisplayMemberPath=ASLDisplayMemberPath；
}
私有无效测试\u已加载（对象发送器，路由目标e）
{
（发送方为TextBlock）？.SetBinding（TextBlock.TextProperty，ASLDisplayMemberPath）；
}
}
public class MainWindowViewModel
{
public ObservableCollection<Model> Models { get; set; }
public ObservableCollection<object> SelectedModels { get; set; }
public MainWindowViewModel()
{
Models = new ObservableCollection<Model>()
{
new Model() {FirstName = "Amelia", Age = 0},
new Model() {FirstName = "Bruno", Age = 5},
new Model() {FirstName = "Colin", Age = 47},
new Model() {FirstName = "Daniel", Age = 32},
new Model() {FirstName = "Iza", Age = 28},
new Model() {FirstName = "James", Age = 23},
new Model() {FirstName = "Simon", Age = 23}
};
SelectedModels = new ObservableCollection<object> {Models.FirstOrDefault() };
}
}
公共类MainWindowViewModel
{
公共可观测集合模型{get；set；}
公共ObservableCollection SelectedModels{get；set；}
公共主窗口视图模型（）
{
模型=新的ObservableCollection（）
{
新模型（）{FirstName=“Amelia”，年龄=0}，
新模型（）{FirstName=“Bruno”，Age=5}，
新模型（）{FirstName=“Colin”，年龄=47}，
新模型（）{FirstName=“Daniel”，年龄=32}，
新模型（）{FirstName=“Iza”，Age=28}，
新模型（）{FirstName=“James”，年龄=23}，
新模型（）{FirstName=“Simon”，年龄=23}
};
SelectedModels=new ObservableCollection{Models.FirstOrDefault（）}；
}
}