更新设备变量信息

HT.Cloud.Web/wwwroot/lib/layui/modules/flow.js

@@ -0,0 +1,176 @@
+/**
+ * flow 流加载组件 
+ */
+ 
+ 
+layui.define('jquery', function(exports){
+  "use strict";
+  
+  var $ = layui.$, Flow = function(options){}
+  ,ELEM_MORE = 'layui-flow-more'
+  ,ELEM_LOAD = '<i class="layui-anim layui-anim-rotate layui-anim-loop layui-icon ">&#xe63e;</i>';
+
+  //主方法
+  Flow.prototype.load = function(options){
+    var that = this, page = 0, lock, isOver, lazyimg, timer;
+    options = options || {};
+    
+    var elem = $(options.elem); if(!elem[0]) return;
+    var scrollElem = $(options.scrollElem || document); //滚动条所在元素
+    var mb = options.mb || 50; //与底部的临界距离
+    var isAuto = 'isAuto' in options ? options.isAuto : true; //是否自动滚动加载
+    var end = options.end || '没有更多了'; //“末页”显示文案
+    
+    //滚动条所在元素是否为document
+    var notDocment = options.scrollElem && options.scrollElem !== document;
+    
+    //加载更多
+    var ELEM_TEXT = '<cite>加载更多</cite>'
+    ,more = $('<div class="layui-flow-more"><a href="javascript:;">'+ ELEM_TEXT +'</a></div>');
+    
+    if(!elem.find('.layui-flow-more')[0]){
+      elem.append(more);
+    }
+    
+    //加载下一个元素
+    var next = function(html, over){ 
+      html = $(html);
+      more.before(html);
+      over = over == 0 ? true : null;
+      over ? more.html(end) : more.find('a').html(ELEM_TEXT);
+      isOver = over;
+      lock = null;
+      lazyimg && lazyimg();
+    };
+    
+    //触发请求
+    var done = function(){
+      lock = true;
+      more.find('a').html(ELEM_LOAD);
+      typeof options.done === 'function' && options.done(++page, next);
+    };
+    
+    done();
+    
+    //不自动滚动加载
+    more.find('a').on('click', function(){
+      var othis = $(this);
+      if(isOver) return;
+      lock || done();
+    });
+    
+    //如果允许图片懒加载
+    if(options.isLazyimg){
+      var lazyimg = that.lazyimg({
+        elem: options.elem + ' img'
+        ,scrollElem: options.scrollElem
+      });
+    }
+    
+    if(!isAuto) return that;
+    
+    scrollElem.on('scroll', function(){
+      var othis = $(this), top = othis.scrollTop();
+      
+      if(timer) clearTimeout(timer);
+      if(isOver || !elem.width()) return; //如果已经结束，或者元素处于隐藏状态，则不执行滚动加载
+      
+      timer = setTimeout(function(){
+        //计算滚动所在容器的可视高度
+        var height = notDocment ? othis.height() : $(window).height();
+        
+        //计算滚动所在容器的实际高度
+        var scrollHeight = notDocment
+          ? othis.prop('scrollHeight')
+        : document.documentElement.scrollHeight;
+
+        //临界点
+        if(scrollHeight - top - height <= mb){
+          lock || done();
+        }
+      }, 100);
+    });
+    
+    return that;
+  };
+  
+  //图片懒加载
+  Flow.prototype.lazyimg = function(options){
+    var that = this, index = 0, haveScroll;
+    options = options || {};
+    
+    var scrollElem = $(options.scrollElem || document); //滚动条所在元素
+    var elem = options.elem || 'img';
+    
+    //滚动条所在元素是否为document
+    var notDocment = options.scrollElem && options.scrollElem !== document;
+    
+    //显示图片
+    var show = function(item, height){
+      var start = scrollElem.scrollTop(), end = start + height;
+      var elemTop = notDocment ? function(){
+        return item.offset().top - scrollElem.offset().top + start;
+      }() : item.offset().top;
+
+      /* 始终只加载在当前屏范围内的图片 */
+      if(elemTop >= start && elemTop <= end){
+        if(item.attr('lay-src')){
+          var src = item.attr('lay-src');
+          layui.img(src, function(){
+            var next = that.lazyimg.elem.eq(index);
+            item.attr('src', src).removeAttr('lay-src');
+            
+            /* 当前图片加载就绪后，检测下一个图片是否在当前屏 */
+            next[0] && render(next);
+            index++;
+          }, function(){
+            var next = that.lazyimg.elem.eq(index);
+            item.removeAttr('lay-src');
+          });
+        }
+      }
+    }, render = function(othis, scroll){
+      
+      //计算滚动所在容器的可视高度
+      var height = notDocment ? (scroll||scrollElem).height() : $(window).height();
+      var start = scrollElem.scrollTop(), end = start + height;
+
+      that.lazyimg.elem = $(elem);
+
+      if(othis){
+        show(othis, height);
+      } else {
+        //计算未加载过的图片
+        for(var i = 0; i < that.lazyimg.elem.length; i++){
+          var item = that.lazyimg.elem.eq(i), elemTop = notDocment ? function(){
+            return item.offset().top - scrollElem.offset().top + start;
+          }() : item.offset().top;
+          
+          show(item, height);
+          index = i;
+          
+          //如果图片的top坐标，超出了当前屏，则终止后续图片的遍历
+          if(elemTop > end) break;
+        }
+      }
+    };
+    
+    render();
+    
+    if(!haveScroll){
+      var timer;
+      scrollElem.on('scroll', function(){
+        var othis = $(this);
+        if(timer) clearTimeout(timer)
+        timer = setTimeout(function(){
+          render(null, othis);
+        }, 50);
+      }); 
+      haveScroll = true;
+    }
+    return render;
+  };
+  
+  //暴露接口
+  exports('flow', new Flow());
+});