安卓4.1 下拉刷新拉不动

机型：联想P770
4.4系统和网页浏览器正常

//初始加载
if (mui.os.plus) {
setTimeout(function(){
mui.init({
pullRefresh: {
container: '#pullrefresh',
down: {
callback: pulldownRefresh
},
up: {
contentrefresh: '正在加载...',
callback: pullupRefresh
}
}
});
},500);
mui.plusReady(function() {
setTimeout(function() {
mui('#pullrefresh').pullRefresh().pullupLoading();
}, 1000);
});
} else {
mui.ready(function() {
mui.init({
pullRefresh: {
container: '#pullrefresh',
down: {
callback: pulldownRefresh
},
up: {
contentrefresh: '正在加载...',
callback: pullupRefresh
}
}
});
mui('#pullrefresh').pullRefresh().pullupLoading();
});
}