I feel like I've missed something obvious, but when creating a custom control in Silverlight I can declare properties as public and they will be exposed when making XAML declarations, so I can easily do something like this:
public class MyControl : UserControl
{
public string Title {get; set;}
}
And this:
<local:MyControl Title="Hello World" />
However properties are not always simple types, I may have a complex property, like a list that defines 1 or more columns and identifies a field to be bound to it. With existing controls the syntax for defining these values in XAML is straight forward:
<local:MyControl Title="People List">
<local:MyControl.Columns>
<local:MyControlColumn Heading="Column 1" Binding="{Binding Name}" />
<local:MyControlColumn Heading="Column 2" Binding="{Binding Age}" />
</local:MyControl.Columns>
</local:MyControl>
However I'm at a loss of how to make this work in the class definition:
public class MyControl : UserControl
{
public string Title {get; set;}
public IEnumerable ItemSource {get; set;}
public ObservableCollection<MyControlColumn> Columns {get; set;} // ?
}
public class My开发者_开发问答ControlColumn
{
public string Heading {get; set;}
public ??? Binding {get; set;} // ?
}
Can anyone point me in the right direction for making exposed list and binding properties?
For the Columns
collection create a backing private variable to hold an instance collection and remove the set accessor:-
private ObservableCollection<MyControlColumn> _columns = new ObservableCollection<MyControlColumn>();
public ObservableCollection<MyControlColumn> Columns {get { return _columns; } }
For the Binding property it looks like what you might want is the Binding type itself System.Windows.Data.Binding
. However I think I'd need to know a little more about what you intend to do with the object once you've got it.
You should consider making the MyControl
Title
property a DependencyProperty:-
public string Title
{
get { return (string)GetValue(TitleProperty); }
set { SetValue(TitleProperty, value); }
}
public static readonly DependencyProperty TitleProperty =
DependencyProperty.Register("Title", typeof(string), typeof(MyControl), null);
Similarly for the ItemSource
although you should also rename to ItemsSource
to keep convention with existing controls.
I can't help feel there is some re-invention of the wheel here, does DataGrid or ListBox or some other similar control not cut it for you?
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