双击事件

void BackHome(){            if (Application.platform==RuntimePlatform.Android&&Input.GetKeyDown(KeyCode.Escape)) {                a+=1;                StartCoroutine("aValueClear",0.4f);            }            if (a == 2) {                Debug.Log("quit");                Application.Quit ();            }            if (Application.platform==RuntimePlatform.Android&&Input.GetKeyDown(KeyCode.Home)) {                Application.Quit();            }        }