fix(treetable): 修复 treeTable 由 #1808，#1792 导致的一些问题 (#1828)

* fix(treeTable): 重载时格式化图标异常

* fix(treeTable): 异步加载时, 加载图标异常

* fix(treeTable): 异步加载节点异常

related: #1792

src/modules/treeTable.js

@@ -213,10 +213,14 @@ layui.define(['table'], function (exports) {
     }
 
     // 处理图标
+    if(options && options.tree && options.tree.view){
       layui.each(ICON_PROPS, function(i, iconProp){
+        if(options.tree.view[iconProp] !== undefined){
           options.tree.view[iconProp] = that.normalizedIcon(options.tree.view[iconProp]);
+        }
       })
     }
+  }
 
   Class.prototype.init = function () {
     var that = this;
@@ -527,7 +531,9 @@ layui.define(['table'], function (exports) {
 
     var update = function(data, parentIndex){
       layui.each(data, function (i1, item1) {
+        if (!(isParentKey in item1)) {
           item1[isParentKey] = !!(item1[childrenKey] && item1[childrenKey].length);
+        }
         item1[LAY_DATA_INDEX_HISTORY] = item1[LAY_DATA_INDEX];
         item1[LAY_PARENT_INDEX] = parentIndex = parentIndex || '';
         var dataIndex = item1[LAY_DATA_INDEX] = (parentIndex ? parentIndex + '-' : '') + i1;
@@ -587,6 +593,7 @@ layui.define(['table'], function (exports) {
 
     // 找到表格中的同类节点（需要找到lay-data-index一致的所有行）
     var trsElem = tableViewElem.find('tr[lay-data-index="' + dataIndex + '"]');
+    var flexIconElem = trsElem.find('.layui-table-tree-flexIcon');
     treeTableThat.updateNodeIcon({
       scopeEl: trsElem,
       isExpand: trExpand,
@@ -1310,6 +1317,8 @@ layui.define(['table'], function (exports) {
 
     var options = that.getOptions();
     var treeOptions = options.tree;
+    var isParentKey = treeOptions.customName.isParent;
+    var childrenKey = treeOptions.customName.children;
     var tableView = options.elem.next();
     var delNode;
     var indexArr = [];
@@ -1360,13 +1369,14 @@ layui.define(['table'], function (exports) {
       tableView.find('tr[data-level="0"][lay-data-index="' + item4[LAY_DATA_INDEX] + '"]').attr('data-index', i4);
     })
     options.hasNumberCol && formatNumber(that);
-    // 更新父节点图标状态
+    // 更新父节点状态
     if(nodeP){
       var trEl =  tableView.find('tr[lay-data-index="' + nodeP[LAY_DATA_INDEX] + '"]');
+      nodeP[isParentKey] = !!(nodeP[childrenKey] && nodeP[childrenKey].length);
       that.updateNodeIcon({
         scopeEl: trEl,
         isExpand: nodeP[LAY_EXPAND],
-        isParent: nodeP[treeOptions.customName.isParent],
+        isParent: nodeP[isParentKey],
       });  
     }