Problem mit der Mehrfachauswahl-Combobox-Steuerung in Windows 8
Ich erstelle eine Mehrfachauswahl-Combobox in Windows 8, wie in der folgenden Abbildung gezeigt:
Hierfür habe ich einen benutzerdefinierten Steuercode erstellt, für den Folgendes angegeben ist: Das Problem mit dem folgenden Code besteht darin, dass 1. beim Auswählen aller Elemente nicht alle ausgewählt werden. 2. Ausgewählte Elemente werden nicht im Textfeld angezeigt
Wie kann ich das beheben? Brauchen Sie Hilfe ASAP pls
XAML:
<UserControl
x:Class="App5.MultiSelectComboBox"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:App5"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
d:DesignHeight="300"
x:Name="thisUC"
d:DesignWidth="400">
<ComboBox
x:Name="MultiSelectCombo"
ScrollViewer.HorizontalScrollBarVisibility="Auto"
ScrollViewer.VerticalScrollBarVisibility="Auto"
Width="400" Height="20"
>
<ComboBox.ItemTemplate>
<DataTemplate>
<CheckBox Content="{Binding Title}" Foreground="Black"
IsChecked="{Binding ElementName=thisUC, Path=IsSelected, Mode=TwoWay}"
Click="CheckBox_Click" />
</DataTemplate>
</ComboBox.ItemTemplate>
<ControlTemplate TargetType="ComboBox">
<Grid >
<ToggleButton
x:Name="ToggleButton"
Grid.Column="2" IsChecked="{TemplateBinding IsDropDownOpen}"
ClickMode="Press" HorizontalContentAlignment="Left" >
<ToggleButton.Template>
<ControlTemplate>
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="18"/>
</Grid.ColumnDefinitions>
<Border
x:Name="Border"
Grid.ColumnSpan="2"
CornerRadius="2"
Background="White"
BorderBrush="Black"
BorderThickness="1,1,1,1" />
<Border
x:Name="BorderComp"
Grid.Column="0"
CornerRadius="2"
Margin="1"
Background="White"
BorderBrush="Black"
BorderThickness="0,0,0,0" >
<TextBlock Foreground="Black" Text="{TemplateBinding TextValue}"
Padding="3" />
</Border>
<Path
x:Name="Arrow"
Grid.Column="1"
Fill="Black"
HorizontalAlignment="Center"
VerticalAlignment="Center"
Data="M 0 0 L 4 4 L 8 0 Z"/>
</Grid>
</ControlTemplate>
</ToggleButton.Template>
</ToggleButton>
<Popup
Name="Popup"
IsOpen="{TemplateBinding IsDropDownOpen}"
>
<Grid
Name="DropDown"
MinWidth="{TemplateBinding ActualWidth}"
MaxHeight="{TemplateBinding MaxDropDownHeight}">
<Border x:Name="DropDownBorder"
BorderThickness="1" Background="White"
BorderBrush="Black"/>
<ScrollViewer Margin="4,6,4,6" DataContext="{Binding}">
<StackPanel />
</ScrollViewer>
</Grid>
</Popup>
</Grid>
<!--<ControlTemplate.Triggers>
<Trigger Property="HasItems" Value="false">
<Setter TargetName="DropDownBorder" Property="MinHeight" Value="95"/>
</Trigger>
<Trigger SourceName="Popup" Property="Popup.AllowsTransparency" Value="true">
<Setter TargetName="DropDownBorder" Property="CornerRadius" Value="4"/>
<Setter TargetName="DropDownBorder" Property="Margin" Value="0,2,0,0"/>
</Trigger>
</ControlTemplate.Triggers>-->
</ControlTemplate>
</ComboBox>
</UserControl>
C #
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.ComponentModel;
using System.IO;
using System.Linq;
using System.Text;
using Windows.Foundation;
using Windows.Foundation.Collections;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Controls.Primitives;
using Windows.UI.Xaml.Data;
using Windows.UI.Xaml.Input;
using Windows.UI.Xaml.Media;
using Windows.UI.Xaml.Navigation;
// The User Control item template is documented at http://go.microsoft.com/fwlink/?LinkId=234236
namespace App5
{
public sealed partial class MultiSelectComboBox : UserControl
{
private ObservableCollection<Node> _nodeList;
public MultiSelectComboBox()
{
InitializeComponent();
_nodeList = new ObservableCollection<Node>();
}
#region Dependency Properties
public static readonly DependencyProperty ItemsSourceProperty =
DependencyProperty.Register("ItemsSource", typeof(Dictionary<string, object>), typeof(MultiSelectComboBox), new PropertyMetadata(null,
new PropertyChangedCallback(MultiSelectComboBox.OnItemsSourceChanged)));
public static readonly DependencyProperty SelectedItemsProperty =
DependencyProperty.Register("SelectedItems", typeof(Dictionary<string, object>), typeof(MultiSelectComboBox), new PropertyMetadata(null,
new PropertyChangedCallback(MultiSelectComboBox.OnSelectedItemsChanged)));
public static readonly DependencyProperty TextProperty =
DependencyProperty.Register("TextValue", typeof(string), typeof(MultiSelectComboBox), new PropertyMetadata(null));
public static readonly DependencyProperty DefaultTextProperty =
DependencyProperty.Register("DefaultText", typeof(string), typeof(MultiSelectComboBox), new PropertyMetadata(null));
public Dictionary<string, object> ItemsSource
{
get { return (Dictionary<string, object>)GetValue(ItemsSourceProperty); }
set
{
SetValue(ItemsSourceProperty, value);
}
}
public Dictionary<string, object> SelectedItems
{
get { return (Dictionary<string, object>)GetValue(SelectedItemsProperty); }
set
{
SetValue(SelectedItemsProperty, value);
}
}
public string TextValue
{
get { return (string)GetValue(TextProperty); }
set { SetValue(TextProperty, value); }
}
public string DefaultText
{
get { return (string)GetValue(DefaultTextProperty); }
set { SetValue(DefaultTextProperty, value); }
}
#endregion
#region Events
private static void OnItemsSourceChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
MultiSelectComboBox control = (MultiSelectComboBox)d;
control.DisplayInControl();
}
private static void OnSelectedItemsChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
MultiSelectComboBox control = (MultiSelectComboBox)d;
control.SelectNodes();
control.SetText();
}
private void CheckBox_Click(object sender, RoutedEventArgs e)
{
CheckBox clickedBox = (CheckBox)sender;
if (clickedBox.Content == "All")
{
if (clickedBox.IsChecked.Value)
{
foreach (Node node in _nodeList)
{
node.IsSelected = true;
}
}
else
{
foreach (Node node in _nodeList)
{
node.IsSelected = false;
}
}
}
else
{
int _selectedCount = 0;
foreach (Node s in _nodeList)
{
if (s.IsSelected && s.Title != "All")
_selectedCount++;
}
if (_selectedCount == _nodeList.Count - 1)
_nodeList.FirstOrDefault(i => i.Title == "All").IsSelected = true;
else
_nodeList.FirstOrDefault(i => i.Title == "All").IsSelected = false;
}
SetSelectedItems();
SetText();
}
#endregion
#region Methods
private void SelectNodes()
{
foreach (KeyValuePair<string, object> keyValue in SelectedItems)
{
Node node = _nodeList.FirstOrDefault(i => i.Title == keyValue.Key);
if (node != null)
node.IsSelected = true;
}
}
private void SetSelectedItems()
{
if (SelectedItems == null)
SelectedItems = new Dictionary<string, object>();
SelectedItems.Clear();
foreach (Node node in _nodeList)
{
if (node.IsSelected && node.Title != "All")
{
if (this.ItemsSource.Count > 0)
SelectedItems.Add(node.Title, this.ItemsSource[node.Title]);
}
}
}
private void DisplayInControl()
{
_nodeList.Clear();
if (this.ItemsSource.Count > 0)
_nodeList.Add(new Node("All"));
foreach (KeyValuePair<string, object> keyValue in this.ItemsSource)
{
Node node = new Node(keyValue.Key);
_nodeList.Add(node);
}
MultiSelectCombo.ItemsSource = _nodeList;
}
private void SetText()
{
if (this.SelectedItems != null)
{
StringBuilder displayText = new StringBuilder();
foreach (Node s in _nodeList)
{
if (s.IsSelected == true && s.Title == "All")
{
displayText = new StringBuilder();
displayText.Append("All");
break;
}
else if (s.IsSelected == true && s.Title != "All")
{
displayText.Append(s.Title);
displayText.Append(',');
}
}
this.TextValue = displayText.ToString().TrimEnd(new char[] { ',' });
}
// set DefaultText if nothing else selected
if (string.IsNullOrEmpty(this.TextValue))
{
this.TextValue = this.DefaultText;
}
}
#endregion
}
public class Node : INotifyPropertyChanged
{
private string _title;
private bool _isSelected;
#region ctor
public Node(string title)
{
Title = title;
}
#endregion
#region Properties
public string Title
{
get
{
return _title;
}
set
{
_title = value;
NotifyPropertyChanged("Title");
}
}
public bool IsSelected
{
get
{
return _isSelected;
}
set
{
_isSelected = value;
NotifyPropertyChanged("IsSelected");
}
}
#endregion
public event PropertyChangedEventHandler PropertyChanged;
protected void NotifyPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
}
}