/// <summary>
/// Mark the Graphic and the canvas as having been changed.
/// </summary>
protected override void OnEnable()
{
base.OnEnable();
CacheCanvas();
BrandoUIGraphicRegistry.RegisterGraphicForCanvas(canvas, this); //注册至 Canvas
#if UNITY_EDITOR
BrandoGraphicRebuildTracker.TrackGraphic(this);
#endif
if (s_WhiteTexture == null)
{
s_WhiteTexture = Texture2D.whiteTexture;
}
SetAllDirty(); //设置为脏，等待渲染
}
/// <summary>
/// Clear references.
/// </summary>
protected override void OnDisable()
{
#if UNITY_EDITOR
BrandoGraphicRebuildTracker.UnTrackGraphic(this);
#endif
//从 Canvas 中注销
BrandoUIGraphicRegistry.UnregisterGraphicForCanvas(canvas, this);
BrandoCanvasUpdateRegistry.UnRegisterCanvasElementForRebuild(this);
if (canvasRenderer != null)
{
canvasRenderer.Clear();
}
LayoutRebuilder.MarkLayoutForRebuild(rectTransform);
base.OnDisable();
}