【发布时间】：2011-03-20 00:25:51
【问题描述】：
试图理解WPF的这个绑定过程。
查看底部的代码。
在我的“viewmodel”中，查看底部的代码，我有一个可观察的集合，它用项目填充列表视图。那是一个包含一个名为符号的路径，用于在组合框中设置选定的索引。现在我的问题是我需要先从另一个列表填充组合框，然后再将其添加到列表视图（一些默认值）。 由于我刚开始使用 WPF，我认为也许您可以在同一个类中使用 2 个不同的 ObservableCollections 来实现这一点，但这不起作用。那么如何在数据模板绑定/添加到列表视图之前使用默认值填充数据模板？
这是我用来填充列表视图的，请参阅底部的 viewmodelcontacts。
我还尝试使用可以在组合框中使用的新 observablecollection 添加另一个类，但我也没有让它工作。 应填充的数据来自我的应用程序中作为资源的 XML 文件。
另一个问题，是否可以向图像添加命令？还是只能从从 button_base 类继承的控件中获得命令？我想在元素旁边使用图像，当用户单击该图像时，他们会删除该元素。
- 根据下面的答案，是否可以不添加按钮，因为我不想要按钮的感觉（例如悬停和单击时）*
Window.xaml：
<r:RibbonWindow x:Class="Onyxia_KD.Windows.ContactWorkspace"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:r="clr-namespace:Microsoft.Windows.Controls.Ribbon;assembly=RibbonControlsLibrary"
Title="Contact card" ResizeMode="NoResize" Height="600" Width="600"
Background="White">
<r:RibbonWindow.Resources>
<DataTemplate x:Key="cardDetailFieldTemplate">
<TextBox Text="{Binding Path=Field}" MinWidth="150"></TextBox>
</DataTemplate>
<DataTemplate x:Key="cardDetailValueTemplate">
<TextBox Text="{Binding Path=Value}" MinWidth="150"></TextBox>
</DataTemplate>
<DataTemplate x:Key="cardDetailSymbolTemplate">
<!-- Here is the problem. Populating this with some default values for each entry before the selectedIndex is bound from the datasource -->
<ComboBox SelectedIndex="{Binding Path=Symbol}" DataContext="_vmSettings" ItemsSource="{Binding Symbols}" Grid.Column="1" Margin="0,0,10,0" VerticalAlignment="Center" HorizontalAlignment="Center">
<ListViewItem Padding="0,3,0,3" Content="{Binding Path=Value}" />
</ComboBox>
</DataTemplate>
<DataTemplate x:Key="cardDetailCategoryTemplate">
<ComboBox SelectedIndex="{Binding Path=Category}" Grid.Column="1" Margin="0,0,10,0" VerticalAlignment="Center" HorizontalAlignment="Center">
<!--same as the combobox above but categories instead of symbols-->
</ComboBox>
</DataTemplate>
</r:RibbonWindow.Resources>
...
<ListView ItemsSource="{Binding ContactData}" Foreground="Black" SelectionMode="Single" x:Name="cardDetailList" KeyDown="cardDetailList_KeyDown">
<ListView.View>
<GridView>
<GridViewColumn Header="Category" Width="auto" CellTemplate="{StaticResource cardDetailCategoryTemplate}"></GridViewColumn>
<GridViewColumn Header="Field" Width="auto" CellTemplate="{StaticResource cardDetailFieldTemplate}"></GridViewColumn>
<GridViewColumn Header="Symbol" Width="70" CellTemplate="{StaticResource cardDetailSymbolTemplate}"></GridViewColumn>
<GridViewColumn Header="Value" Width="auto" CellTemplate="{StaticResource cardDetailValueTemplate}"></GridViewColumn>
</GridView>
</ListView.View>
</ListView>
后面的代码：
private ViewModelContacts _vm;
public ContactWorkspace()
{
InitializeComponent();
_vm = new ViewModelContacts();
this.DataContext = _vm;
}
private void Run_MouseUp(object sender, MouseButtonEventArgs e)
{
_vm.AddNewDetail();
}
private void Image_MouseUp(object sender, MouseButtonEventArgs e)
{
_vm.AddNewDetail();
}
private void cardDetailList_KeyDown(object sender, KeyEventArgs e)
{
if (e.Key == Key.Delete)
{
if (MessageBox.Show("Are you sure that you want to delete this?", "Warning!", MessageBoxButton.YesNo, MessageBoxImage.Warning) == MessageBoxResult.Yes)
{
_vm.RemoveDetail(cardDetailList.SelectedIndex);
}
}
}
ViewModel 联系人：
public ObservableCollection<ContactCardData> ContactData { get; set; }
public ViewModelContacts()
{
ContactData = new ObservableCollection<ContactCardData>();
Populate();
}
private void Populate()
{
ContactData.Add(new ContactCardData("Test", 0, 0, "Value123"));
ContactData.Add(new ContactCardData("Test2", 1, 1, "Value1234"));
ContactData.Add(new ContactCardData("Test3", 2, 2, "Value1235"));
ContactData.Add(new ContactCardData("Test4", 3, 3, "Value12356"));
}
public void UpdateNode()
{
ContactData.ElementAt(0).Value = "Giraff";
}
public void AddNewDetail()
{
ContactData.Add(new ContactCardData());
}
public void RemoveDetail(int position)
{
ContactData.RemoveAt(position);
}
ViewModelContactData：
public class ContactCardData : DependencyObject
{
public int Category
{
get { return (int)GetValue(CategoryProperty); }
set { SetValue(CategoryProperty, value); }
}
// Using a DependencyProperty as the backing store for Category. This enables animation, styling, binding, etc...
public static readonly DependencyProperty CategoryProperty =
DependencyProperty.Register("Category", typeof(int), typeof(ContactCardData), new UIPropertyMetadata(0));
public string Field
{
get { return (string)GetValue(FieldProperty); }
set { SetValue(FieldProperty, value); }
}
// Using a DependencyProperty as the backing store for Field. This enables animation, styling, binding, etc...
public static readonly DependencyProperty FieldProperty =
DependencyProperty.Register("Field", typeof(string), typeof(ContactCardData), new UIPropertyMetadata(""));
public string Value
{
get { return (string)GetValue(ValueProperty); }
set { SetValue(ValueProperty, value); }
}
// Using a DependencyProperty as the backing store for Value. This enables animation, styling, binding, etc...
public static readonly DependencyProperty ValueProperty =
DependencyProperty.Register("Value", typeof(string), typeof(ContactCardData), new UIPropertyMetadata(""));
public int Symbol
{
get { return (int)GetValue(SymbolProperty); }
set { SetValue(SymbolProperty, value); }
}
// Using a DependencyProperty as the backing store for Symbol. This enables animation, styling, binding, etc...
public static readonly DependencyProperty SymbolProperty =
DependencyProperty.Register("Symbol", typeof(int), typeof(ContactCardData), new UIPropertyMetadata(0));
public ContactCardData()
{
}
public ContactCardData(string field, int category, int symbol, string value)
{
this.Symbol = symbol;
this.Category = category;
this.Field = field;
this.Value = value;
}
}
【问题讨论】：
标签： wpf data-binding binding observablecollection