AttributeTableBuilder.AddCallback Method
Adds a callback that is invoked when metadata for the specified type is needed.
Namespace: Microsoft.Windows.Design.Metadata
Assembly: Microsoft.Windows.Design (in Microsoft.Windows.Design.dll)
Syntax
'Declaration
Public Sub AddCallback ( _
type As Type, _
callback As AttributeCallback _
)
'Usage
Dim instance As AttributeTableBuilder
Dim type As Type
Dim callback As AttributeCallback
instance.AddCallback(type, callback)
public void AddCallback(
Type type,
AttributeCallback callback
)
public:
void AddCallback(
Type^ type,
AttributeCallback^ callback
)
public function AddCallback(
type : Type,
callback : AttributeCallback
)
Parameters
type
Type: System.TypeThe type to add metadata attributes to.
callback
Type: Microsoft.Windows.Design.Metadata.AttributeCallbackAn AttributeCallback which adds metadata to Type.
Remarks
Callback can add metadata to the attribute table on demand, which is more efficient than adding metadata when the table is created.
Use the AddCallback method with the AttributeCallbackBuilder class when you are building a large attribute table.
Examples
The following code example shows how to use the AddCallback method and the AttributeTableBuilder class to create and populate an attribute table. This code example is part of a larger example provided for the AttributeCallbackBuilder class.
// Container for any general design-time metadata to initialize.
// Designers look for a type in the design-time assembly that
// implements IRegisterMetadata. If found, designers instantiate
// this class and call its Register() method automatically.
internal class Metadata : IRegisterMetadata
{
// Called by the designer to register any design-time metadata.
public void Register()
{
AttributeTableBuilder builder = new AttributeTableBuilder();
// Build the attribute table by using the AttributeCallbackBuilder
// class. The attribute table is not populated until the designer
// needs it, which is more efficient for large attribute tables.
builder.AddCallback(
typeof(Button),
delegate(AttributeCallbackBuilder callbackBuilder)
{
callbackBuilder.AddCustomAttributes(
new DefaultPropertyAttribute("Content"));
// Apply the ReadOnlyAttribute to the Background property
// of the Button class.
callbackBuilder.AddCustomAttributes(
"Background",
new ReadOnlyAttribute(true));
PropertyDescriptorCollection properties =
TypeDescriptor.GetProperties(typeof(Button));
PropertyDescriptor pd = properties["Foreground"];
callbackBuilder.AddCustomAttributes(
pd,
new ReadOnlyAttribute(true));
callbackBuilder.AddCustomAttributes(
Button.WidthProperty,
new TypeConverterAttribute(typeof(LengthConverter)),
new DescriptionAttribute("This is the width"));
MemberInfo[] members = typeof(Button).GetMember("Height");
callbackBuilder.AddCustomAttributes(
members[0],
new ReadOnlyAttribute(true));
});
MetadataStore.AddAttributeTable(builder.CreateTable());
}
}
.NET Framework Security
- Full trust for the immediate caller. This member cannot be used by partially trusted code. For more information, see Using Libraries from Partially Trusted Code.
See Also
Reference
Microsoft.Windows.Design.Metadata Namespace