var   myScroll,
  pullDownEl, pullDownOffset,
  pullUpEl, pullUpOffset,
  generatedCount = 0;
 
/**
 * 下拉刷新 （自定义实现此方法）
 * myScroll.refresh(); 数据加载完成后，调用界面更新方法
 */
function pullDownAction () {
  setTimeout(function () {  
    var el, li, i;
    el = document.getElementById('thelist');
 
    for (i=0; i<3; i++) {
      li = document.createElement('li');
      li.innerText = 'Generated row ' + (++generatedCount);
      el.insertBefore(li, el.childNodes[0]);
    }
     
    myScroll.refresh();   //数据加载完成后，调用界面更新方法 
  }, 1000); 
}
 
/**
 * 滚动翻页 （自定义实现此方法）
 * myScroll.refresh();   // 数据加载完成后，调用界面更新方法
 */
function pullUpAction () {
  setTimeout(function () {  // <-- Simulate network congestion, remove setTimeout from production!
    var el, li, i;
    el = document.getElementById('thelist');
 
    for (i=0; i<3; i++) {
      li = document.createElement('li');
      li.innerText = 'Generated row ' + (++generatedCount);
      el.appendChild(li, el.childNodes[0]);
    }
     
    myScroll.refresh();   //数据加载完成后，调用界面更新方法
  }, 1000); 
}
 
/**
 * 初始化iScroll控件
 */
function loaded() {
  pullDownEl = document.getElementById('pullDown');
  pullDownOffset = pullDownEl.offsetHeight;
  pullUpEl = document.getElementById('pullUp'); 
  pullUpOffset = pullUpEl.offsetHeight;
   
  myScroll = new iScroll('wrapper', {
    scrollbarClass: 'myScrollbar',
    useTransition: false,
    topOffset: pullDownOffset,
    onRefresh: function () {
      if (pullDownEl.className.match('loading')) {
        pullDownEl.className = '';
        pullDownEl.querySelector('.pullDownLabel').innerHTML = '下拉刷新...';
      } else if (pullUpEl.className.match('loading')) {
        pullUpEl.className = '';
        pullUpEl.querySelector('.pullUpLabel').innerHTML = '上拉加载更多...';
      }
    },
    onScrollMove: function () {
      if (this.y > 5 && !pullDownEl.className.match('flip')) {
        pullDownEl.className = 'flip';
        pullDownEl.querySelector('.pullDownLabel').innerHTML = '松手开始更新...';
        this.minScrollY = 0;
      } else if (this.y < 5 && pullDownEl.className.match('flip')) {
        pullDownEl.className = '';
        pullDownEl.querySelector('.pullDownLabel').innerHTML = '下拉刷新...';
        this.minScrollY = -pullDownOffset;
      } else if (this.y < (this.maxScrollY - 5) && !pullUpEl.className.match('flip')) {
        pullUpEl.className = 'flip';
        pullUpEl.querySelector('.pullUpLabel').innerHTML = '松手开始更新...';
        this.maxScrollY = this.maxScrollY;
      } else if (this.y > (this.maxScrollY + 5) && pullUpEl.className.match('flip')) {
        pullUpEl.className = '';
        pullUpEl.querySelector('.pullUpLabel').innerHTML = '上拉加载更多...';
        this.maxScrollY = pullUpOffset;
      }
    },
    onScrollEnd: function () {
      if (pullDownEl.className.match('flip')) {
        pullDownEl.className = 'loading';
        pullDownEl.querySelector('.pullDownLabel').innerHTML = '加载中...';        
        pullDownAction();  // ajax call
      } else if (pullUpEl.className.match('flip')) {
        pullUpEl.className = 'loading';
        pullUpEl.querySelector('.pullUpLabel').innerHTML = '加载中...';        
        pullUpAction(); // ajax call
      }
    }
  });
   
  setTimeout(function () { document.getElementById('wrapper').style.left = '0'; }, 800);
}
 
//初始化绑定iScroll控件
document.addEventListener('touchmove', function (e) { e.preventDefault(); }, false);
document.addEventListener('DOMContentLoaded', loaded, false);