How to use callback when PDF loaded

[BearXmX]

when i use web viewer draw PDF file and i use iframe to load,the iframe src like /web/viewer.html?file=blob

when PDF loaded, i wish the iframe can use postmessage api send some message to parent container, so how can I use lifeCycles in the
viewer.html

Thank you very much!

[moon476607596]

Have you solved this problem？