type没有可访问的构造函数

Question

我似乎遇到了我创建的课程的问题。当我尝试使用以下代码在wpf窗口的xaml文件中创建它的实例时，我收到错误“type has no accessible constructors”：

<local:TextStyleDefinition x:Key="deleteItem" StyleName="Delete Notes" ItsId="-1"/>

TextStyleDefinition类定义如下：

public class TextStyleDefinition : BaseStyleDefinition
{
    public string TextFontName { get; set; }
    public string TextSize { get; set; }
    public string TextTabSize { get; set; }
    public int TextBold { get; set; }
    public int TextItalic { get; set; }
    public int TextUnderline { get; set; }
    public string TextWidthFactor { get; set; }

    public TextStyleDefinition() : base()
    {
        System.Diagnostics.Debug.WriteLine("TSD ctor : blank");
    }

    // override object.Equals
    public override bool Equals(object obj)
    {
        if (obj == null || GetType() != obj.GetType())
        {
            return false;
        }

        TextStyleDefinition lsd = obj as TextStyleDefinition;
        if (this.StyleName != lsd.StyleName ||
            this.ItsId != lsd.ItsId)
            return false;

        return true;
    }

    // override object.GetHashCode
    public override int GetHashCode()
    {
        return ItsId;
    }
}

因此BaseStyleDefinition类是：

public abstract class BaseStyleDefinition : INotifyPropertyChanged
{
    public string StyleName { get; set; }
    public int ItsId { get; set; }

    public BaseStyleDefinition() : base() { }

    public event PropertyChangedEventHandler PropertyChanged;
    protected virtual void OnPropertyChanged(string propertyName)
    {
        PropertyChangedEventHandler handler = PropertyChanged;
        if (handler != null)
            handler(this, new PropertyChangedEventArgs(propertyName));
    }

    // override object.Equals
    public override bool Equals(object obj)
    {
        if (obj == null || GetType() != obj.GetType())
            return false;
        BaseStyleDefinition rsd = obj as BaseStyleDefinition;
        if (this.StyleName != rsd.StyleName ||
            this.ItsId != rsd.ItsId)
            return false;
        return true;
    }

    // override object.GetHashCode
    public override int GetHashCode()
    {
        return ItsId;
    }
}

正如你所看到的，我有无参数构造函数，类是公共的，所以它不是明显的问题。代码编译正常并正确执行，但VS2015将xaml中的行突出显示为错误，并且不会在wpf设计器中显示该窗口。

有没有猜到它会是什么？