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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.Extensibility (in Microsoft.Windows.Design.Extensibility.dll)

Syntax

'Declaration
Public Sub AddCallback ( _
    type As Type, _
    callback As AttributeCallback _
)
public void AddCallback(
    Type type,
    AttributeCallback callback
)
public:
void AddCallback(
    Type^ type, 
    AttributeCallback^ callback
)
member AddCallback : 
        type:Type * 
        callback:AttributeCallback -> unit 
public function AddCallback(
    type : Type, 
    callback : AttributeCallback
)

Parameters

  • type
    Type: System.Type
    The type to add metadata attributes to.

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 IProvideAttributeTable. If found, designers instantiate 
// this class and access its AttributeTable property automatically.
internal class Metadata : IProvideAttributeTable
{
    // Accessed by the designer to register any design-time metadata.
    public AttributeTable AttributeTable
    {
        get
        {
            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));
                });

            return builder.CreateTable();
        }
    }
}

.NET Framework Security

See Also

Reference

AttributeTableBuilder Class

Microsoft.Windows.Design.Metadata Namespace

AttributeTable

AttributeCallbackBuilder