我想使用一个用户控制从不同的组件,DataGridTemplateColumn。 我已经看了大量的实例和问题,像this, this, this和这 。我想不通,为什么我的code不工作。 在这里,它是:
I want to use an User control from a different assembly as DataGridTemplateColumn. I've already looked at a lot of examples and questions, like this, this, this and this. I can't figure out why my code's not working. Here it is:
<Window x:Class="WpfTemplatesDemo3.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:extraUserControl="clr-namespace:Templates;assembly=Templates"
xmlns:wpfTemplatesDemo3="clr-namespace:WpfTemplatesDemo3"
Title="MainWindow" Height="350" Width="525">
<Grid>
<DataGrid x:Name="TableDataGrid" DataContext="{Binding UpdateSourceTrigger=PropertyChanged}" AutoGenerateColumns="False" >
<DataGrid.Columns>
<DataGridTextColumn Binding="{Binding Name}" Width="*"/>
<DataGridTextColumn Binding="{Binding Age}" Width="*"/>
<DataGridTextColumn Binding="{Binding Description}" Width="2*"/>
<DataGridTemplateColumn Width="3*" >
<DataGridTemplateColumn.CellTemplate>
<DataTemplate>
<extraUserControl:BirthDateControl BirthDayObj="{Binding BirthDay, ElementName=TableDataGrid}" />
</DataTemplate>
</DataGridTemplateColumn.CellTemplate>
</DataGridTemplateColumn>
</DataGrid.Columns>
</DataGrid>
</Grid>
</Window>
namespace WpfTemplatesDemo3
{
public partial class MainWindow : Window
{
public ObservableCollection<Person> Persons { get;set; }
public MainWindow()
{
InitializeComponent();
this.populatePersons();
this.TableDataGrid.ItemsSource = this.Persons;
}
private void populatePersons()
{
this.Persons = new ObservableCollection<Person>();
Persons.Add(new Person { Age = 10, Name = "John0", BirthDay = new BirthDate(1, 2, 3) });
Persons.Add(new Person { Age = 11, Name = "John1", BirthDay = new BirthDate(2, 3, 4) });
Persons.Add(new Person { Age = 12, Name = "John2", BirthDay = new BirthDate(3, 4, 5) });
Persons.Add(new Person { Age = 13, Name = "John3", BirthDay = new BirthDate(4, 5, 6) });
Persons.Add(new Person { Age = 14, Name = "John4", BirthDay = new BirthDate(5, 6, 7) });
Persons.Add(new Person { Age = 15, Name = "John5", BirthDay = new BirthDate(6, 7, 8) });
}
}
}
<UserControl x:Class="Templates.BirthDateControl"
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"
mc:Ignorable="d" d:DesignWidth="300" Height="52.273"
DataContext="{Binding RelativeSource={RelativeSource Self}}"
>
<Grid>
<StackPanel>
<Label Content="Date:"/>
<StackPanel Orientation="Horizontal" >
<TextBox Text="{Binding BirthDayObj.Day}" />
<TextBox Text="{Binding BirthDayObj.Month}"/>
<TextBox Text="{Binding BirthDayObj.Year}" />
</StackPanel>
</StackPanel>
</Grid>
</UserControl>
namespace Templates
{
public partial class BirthDateControl : System.Windows.Controls.UserControl
{
public static DependencyProperty BirthDayObjProperty =
DependencyProperty.Register("BirthDayObj", typeof(BirthDate), typeof(BirthDateControl));
public BirthDate BirthDayObj
{
get
{
return ((BirthDate)GetValue(BirthDayObjProperty));
}
set
{
SetValue(BirthDayObjProperty, value);
}
}
public BirthDateControl()
{
InitializeComponent();
}
}
}
namespace Entities
{
public class Person : INotifyPropertyChanged
{
private string name;
private int age;
private BirthDate _birthDay;
public string Name
{
get { return this.name; }
set {
this.name = value;
this.OnPropertyChanged("Name");
this.OnPropertyChanged("Description");
}
}
public int Age
{
get { return this.age; }
set
{
this.age = value;
this.OnPropertyChanged("Age");
this.OnPropertyChanged("Description");
}
}
public string Description
{
get { return Name + "_" + Age + "_" + BirthDay.Day; }
}
public BirthDate BirthDay
{
get { return this._birthDay; }
set
{
this._birthDay = value;
this.OnPropertyChanged("BirthDate");
this.OnPropertyChanged("Description");
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected void OnPropertyChanged(string propName)
{
if (this.PropertyChanged != null)
this.PropertyChanged(
this, new PropertyChangedEventArgs(propName));
}
}
}
namespace Entities
{
public class BirthDate : INotifyPropertyChanged
{
private int day;
private int month;
private int year;
public BirthDate(int day, int month, int year)
{
this.day = day;
this.month = month;
this.year = year;
}
public int Day {
get { return this.day; }
set
{
this.day = value;
this.OnPropertyChanged("day");
}
}
public int Month {
get { return this.month; }
set
{
this.month = value;
this.OnPropertyChanged("month");
}
}
public int Year {
get { return this.year; }
set
{
this.year = value;
this.OnPropertyChanged("year");
}
}
public event PropertyChangedEventHandler PropertyChanged;
protected void OnPropertyChanged(string propName)
{
if (this.PropertyChanged != null)
this.PropertyChanged(
this, new PropertyChangedEventArgs(propName));
}
}
}
如果我运行它,它会显示在列,但出生日期栏是空的。
If I run it, it will show the columns, but the birthdate columns are empty.
有没有错误或警告,但是这显示在输出:
There are no errors or warnings, but this shows up in Output:
System.Windows.Data Error: 40 : BindingExpression path error: 'BirthDay' property not found on 'object' ''DataGrid' (Name='TableDataGrid')'. BindingExpression:Path=BirthDay; DataItem='DataGrid' (Name='TableDataGrid'); target element is 'BirthDateControl' (Name=''); target property is 'BirthDayObj' (type 'BirthDate')
System.Windows.Data Error: 40 : BindingExpression path error: 'BirthDay' property not found on 'object' ''DataGrid' (Name='TableDataGrid')'. BindingExpression:Path=BirthDay; DataItem='DataGrid' (Name='TableDataGrid'); target element is 'BirthDateControl' (Name=''); target property is 'BirthDayObj' (type 'BirthDate')
System.Windows.Data Error: 40 : BindingExpression path error: 'BirthDay' property not found on 'object' ''DataGrid' (Name='TableDataGrid')'. BindingExpression:Path=BirthDay; DataItem='DataGrid' (Name='TableDataGrid'); target element is 'BirthDateControl' (Name=''); target property is 'BirthDayObj' (type 'BirthDate')
System.Windows.Data Error: 40 : BindingExpression path error: 'BirthDay' property not found on 'object' ''DataGrid' (Name='TableDataGrid')'. BindingExpression:Path=BirthDay; DataItem='DataGrid' (Name='TableDataGrid'); target element is 'BirthDateControl' (Name=''); target property is 'BirthDayObj' (type 'BirthDate')
System.Windows.Data Error: 40 : BindingExpression path error: 'BirthDay' property not found on 'object' ''DataGrid' (Name='TableDataGrid')'. BindingExpression:Path=BirthDay; DataItem='DataGrid' (Name='TableDataGrid'); target element is 'BirthDateControl' (Name=''); target property is 'BirthDayObj' (type 'BirthDate')
System.Windows.Data Error: 40 : BindingExpression path error: 'BirthDay' property not found on 'object' ''DataGrid' (Name='TableDataGrid')'. BindingExpression:Path=BirthDay; DataItem='DataGrid' (Name='TableDataGrid'); target element is 'BirthDateControl' (Name=''); target property is 'BirthDayObj' (type 'BirthDate')
'WpfTemplatesDemo3.exe' (Managed (v4.0.30319)): Loaded 'C:\Windows\Microsoft.Net\assembly\GAC_MSIL\UIAutomationTypes\v4.0_4.0.0.0__31bf3856ad364e35\UIAutomationTypes.dll', Skipped loading symbols. Module is optimized and the debugger option 'Just My Code' is enabled.
System.Windows.Data Error: 40 : BindingExpression path error: 'BirthDay' property not found on 'object' ''DataGrid' (Name='TableDataGrid')'. BindingExpression:Path=BirthDay; DataItem='DataGrid' (Name='TableDataGrid'); target element is 'BirthDateControl' (Name=''); target property is 'BirthDayObj' (type 'BirthDate')
The program '[16364] WpfTemplatesDemo3.exe: Managed (v4.0.30319)' has exited with code 0 (0x0).
我想不通为什么它不会将数据绑定到用户控件。
I can't figure out why it won't bind the data to the user control.
在 DataGridRow
拥有的的DataContext
人
对象。该的DataContext
中的 VisualTree
,因此你的UC具有相同的上下文是继承。为了让你的样品工作:
The DataGridRow
has the DataContext
of Person
object. The DataContext
is inherited among your VisualTree
, thus your UC has the same context. To make your sample work:
BirthDayObjProperty
从UC。
在扔掉这条线从的DataGrid
:的DataContext ={结合UpdateSourceTrigger =的PropertyChanged}
在扔掉这条线在你的UC:的DataContext ={绑定的RelativeSource = {的RelativeSource自}}
您UC绑定可以很简单,如:
Throw away BirthDayObjProperty
from your UC.
Throw away this line from your DataGrid
: DataContext="{Binding UpdateSourceTrigger=PropertyChanged}"
Throw away this line in your UC: DataContext="{Binding RelativeSource={RelativeSource Self}}"
Your UC bindings can be as simple as:
<Grid>
<StackPanel>
<Label Content="Date:"/>
<StackPanel Orientation="Horizontal" >
<TextBox Text="{Binding BirthDay.Day}" />
<TextBox Text="{Binding BirthDay.Month}"/>
<TextBox Text="{Binding BirthDay.Year}" />
</StackPanel>
</StackPanel>
</Grid>
了解更多关于的DataContext
的继承和绑定在一般情况下,
因为你明显地误用它们。
Read more about DataContext
inheritance and bindings in general,
as you're obviously misusing them.