iframe 로딩 확인

1. 상태체크

var loadState = document.getElementById("#iframeId").readyState;

2. 콜백

$("#iframeId").load(function(){

// action

});

http://donzbox.tistory.com/409

http://blog.naver.com/javaking75/220165839270

http://www.w3big.com/ko/jsref/event-frame-onload.html

http://rkysky.tistory.com/93

https://stackoverflow.com/questions/13952942/iframe-readystate-does-not-work-in-chrome

https://bugs.chromium.org/p/chromium/issues/detail?id=32357

https://developer.mozilla.org/en-US/docs/Web/API/Document/readyState