React ES6轮播图定时器的问题

//开启定时器

startTimer(){

//1.拿到scrollView

var scrollView = this.refs.scrollView;

//图片数组

var imgCount = ImgData.data.length;

//2.添加定时器

this.timer = setInterval(()=>{

alert('123');

//2.1设置圆点

var activePage = 0;

//2.2判断

if ((this.state.currentPage + 1)>=imgCount) {

//越界

activePage = 0;

}else{

activePage = this.state.currentPage + 1;

}

//2.3更新UI

this.setState({

currentPage:activePage

});

//2.4 让scrollView滚动起来

var offsetX = activePage * width;

scrollView.scrollResponderScrollTo({x:offsetX, y:0, animated:true});

},this.props.duration);

};

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