/// <summary>
/// 构造一个 FocusTrackerAdorner 对象，并指定它所在的 AdornerLayer 及所在范围。
/// </summary>
/// <param name="layerRoot">layer 对应的根控件。</param>
/// <param name="layer">本 Adorner 所添加到的 Layer。</param>
/// <param name="scope">最外层的范围控件。</param>
/// <param name="scopeLayer">最外层的范围控件对应的 AdornerLayer。</param>
private FocusTrackerAdorner(UIElement layerRoot, AdornerLayer layer, UIElement scope, AdornerLayer scopeLayer)
: base(layerRoot)
{
if (scope == null)
{
throw new ArgumentNullException("scope");
}
if (layer == null)
{
throw new ArgumentNullException("layer");
}
_scope = scope;
_scopeLayer = scopeLayer;
_layerRoot = layerRoot;
_layer = layer;
_children = new UIElementCollection(this, this);
_tracker = new FocusTrackerControl {
Adorner = this
};
_children.Add(_tracker);
this.Loaded += OnLoaded;
scope.GotKeyboardFocus += scope_GotKeyboardFocus;
}
/// <summary>
/// 构造一个 FocusTrackerAdorner 对象，并指定它所在的 AdornerLayer 及所在范围。
/// </summary>
/// <param name="layerRoot">layer 对应的根控件。</param>
/// <param name="layer">本 Adorner 所添加到的 Layer。</param>
/// <param name="scope">最外层的范围控件。</param>
/// <param name="scopeLayer">最外层的范围控件对应的 AdornerLayer。</param>
private FocusTrackerAdorner(UIElement layerRoot, AdornerLayer layer, UIElement scope, AdornerLayer scopeLayer)
: base(layerRoot)
{
if (scope == null) throw new ArgumentNullException("scope");
if (layer == null) throw new ArgumentNullException("layer");
_scope = scope;
_scopeLayer = scopeLayer;
_layerRoot = layerRoot;
_layer = layer;
_children = new UIElementCollection(this, this);
_tracker = new FocusTrackerControl { Adorner = this };
_children.Add(_tracker);
this.Loaded += OnLoaded;
scope.GotKeyboardFocus += scope_GotKeyboardFocus;
}