WPF : UserControl的Initialized事件不会触发

UserControl必须实现ISupportInitialize接口.

/// <summary>
/// Implement ISupportInitialize so that the Initialized event can be attached in XAML.
/// A known bug is that the BeginInit/EndInit will be called twice in WPF 3.*.
/// </summary>

public partial class UcTaskItemNote : ISupportInitialize
{
    private int mInitCalledCount = 0;

    #region ISupportInitialize Members

    void ISupportInitialize.BeginInit()
    {       
        if(this.mInitCalledCount == 0)
        {
            return;
        }
        base.BeginInit();
    }

    void ISupportInitialize.EndInit()
    {
        if (this.mInitCalledCount == 0)
        {
            this.mInitCalledCount++;
            return;
        }
        base.EndInit();
    }

    #endregion
}