参考文章：http://blog.csdn.net/u011185231/article/details/49591383
todo：active和enable的差别？
核心API：
Component.GetComponentInChildren<Transform>()，应该是递归获取所有的child，激活的
GetComponentsInChildren<Transform>(true)，激活和未激活的都get
思路：获取Transform，然后在获取上面的GameObject。然后对child进行操作。
//img_bottomPanel_loading是Image
//GetComponentInChildren获取第一个child
Transform firstChild = img_bottomPanel_loading.GetComponentInChildren<Transform> ();
string name = firstChild.gameObject.name;
Debug.Log ("firstChild:" + name);
//获取所有的children，
Transform[] children = img_bottomPanel_loading.GetComponentsInChildren<Transform> ();
for (int i = 0; i < children.Length; i++) {
string nameTemp = children [i].gameObject.name;
children [i].gameObject.SetActive (false); //hide
Debug.Log ("nameTemp:" + nameTemp);
}
private void setBottomOperatePanelHide(bool hide){
img_bottomPanel_operate.enabled = !hide;
Transform[] children = img_bottomPanel_operate.GetComponentsInChildren<Transform> (true);
foreach(Transform tr in children){
tr.gameObject.SetActive (hide);
}
}