video.js how to set currentTime in safari in iPhone

Other is ok, but the setting of currentTime.

I tried some ways like:

videojs("example_video_1", {}, function() {
    this.currentTime(200);
    this.play();
});

not work.

videojs("example_video_1").ready(function(){
    this.currentTime(200);
});

not work.

var dom = document.getElementById('example_video_1');
dom.addEventListener("loadedmetadata", function() {
    dom.currentTime = 100;
}, false);    // ok for no video.js
videojs(dom);

not work. Even reverse the line of addEventListener and init videojs.

And i tried the videojs event.

var player = videojs("example_video_1");
alert(player.addEvent);
alert(player.addEventListener);

these API is all not exists, so how do i bind Event in videojs?

At last, how to set currentTime in videojs(in safari in iPhone)?