How to solve the BUG that cannot enter the visible area when ztree obtains the selected node_jquery

zTree is a multi-functional "tree plug-in" implemented with jQuery. Excellent performance, flexible configuration, and combination of multiple functions are the biggest advantages of zTree.

zTree Features Editing

● zTree v3.0 divides the core code according to functions, and unnecessary code does not need to be loaded
● Adopting lazy loading technology, tens of thousands of nodes can be easily loaded, and it can basically achieve instant killing even under IE6
● Compatible with IE, FireFox, Chrome, Opera, Safari and other browsers
● Support JSON data
● Supports static and Ajax asynchronous loading of node data
● Supports any skin change/custom icon (relying on css)
● Supports extremely flexible checkbox or radio selection function
● Provides multiple event response callbacks
● Flexible editing (add/delete/modify/check) functions, you can drag and drop nodes at will, and you can drag and drop multiple nodes
● Multiple Tree instances can be generated simultaneously in one page
● Simple parameter configuration to achieve flexible functions

Advantages of zTree Editing

The author of zTree uses his spare time to continuously improve zTree functions, and can also communicate with users in a timely manner and respond to various questions in a timely manner, so that new users can quickly master it. Currently, more and more users are using zTree to replace the original tree plug-in in the system, including the recently released latest version of the QUI framework.

Related plug-in version:

jquery.ztree.exedit-3.4.js

jquery.ztree.all-3.4.js

jquery-1.8.0.js

 function onAsyncSuccess(event, treeId, treeNode, msg) {
     curAsyncCount--;
     if (curStatus == "expand") {
       expandNodes(treeNode.children);
     } else if (curStatus == "async") {
       asyncNodes(treeNode.children);
     } 
     if (curAsyncCount <= ) {
       curStatus = "";
       // 节点定位
       if(devicesSelect.selectNodeId){
         // 节点变成被选中状态
         var zTree = $.fn.zTree.getZTreeObj(zTreeId);
         zTree.cancelSelectedNode();
         $("#" + devicesSelect.selectNodeId + "_a").addClass("curSelectedNode");
         $("#treeDiv").animate({scrollTop:$("#"+devicesSelect.selectNodeId).offset().top-},);//是ms,也可以用slow代替
         devicesSelect.selectNodeId = "";
       }
     }
   } 
   function expandNodes(nodes) {
     if (!nodes) return;
     curStatus = "expand";
     var zTree = $.fn.zTree.getZTreeObj(zTreeId);
     for (var i=, l=nodes.length; i<l; i++) {
       if(ids.indexOf(nodes[i].id) != -){
         if (nodes[i].isParent&&(ids.substring(,ids.indexOf(","))!=nodes[i].id)) {
           if(nodes[i].typeName.indexOf("虚拟")=="-"){
             zTree.expandNode(nodes[i], true, false, false);
           } else if(nodes[i].type.indexOf(type)>"-"){
             zTree.expandNode(nodes[i], true, false, false);
           }
         } else {
           goAsync = true;
         }
       }
     }
     if(goAsync==true){
       var id_ = ids.substring(,ids.indexOf(","));
       var node = zTree.getNodeByParam("id",id_);
       goAsync = false;
       me.curStatus = "";
       me.type = "";
       me.selectNodeId = node.tId;
     }
   } 

Positioning ideas:

1. Suppose you want to locate node A. The unique identifier of node A is objid

2. Get all superior objids from db based on objid, splice them together and save them in the ids variable.

3. Call expandNodes in the onAsyncSuccess method. In this method, pass [if (nodes[i].isParent&&(ids.substring(0,ids.indexOf(","))!=nodes[i].id) )] filter and expand the nodes with id in ids.

4. Under normal circumstances, at the end of expansion, obtain the node A object through [var node = zTree.getNodeByParam("id",id_);] based on objid, and then select it through [zTree.selectNode(node);] node.

In this case, the target node can be located and selected. However, when there is a lot of data with the same parent node as the node, node A may not appear in the visible area. Searching the source code, I found that Ztree uses the [$("#" node.tId).focus().blur();] method to achieve positioning. But unfortunately, there is a BUG.

So, use the scroll bar to control the positioning yourself. The implementation is as follows:

1. Delete [zTree.selectNode(node);] to prevent positioning conflicts

2. In the onAsyncSuccess method, determine when the node is expanded, obtain the offset of node A, and assign the value to the scrollTop attribute of the DIV where the tree is located.

$("#treeDiv1").animate({scrollTop:$("#" devicesSelect.selectNodeId).offset().top-300},1000);//1000 is ms, you can also use slow instead

Note: devicesSelect.selectNodeId is the node tid of node A, obtained through [me.selectNodeId = node.tId]; the id attribute of the div where the treeDiv1 tree is located

3. Cancel the previously selected node: zTree.cancelSelectedNode();

4. Add the selected status class to node A: $("#" devicesSelect.selectNodeId "_a").addClass("curSelectedNode");

The author said lightly: For the second point, I originally wanted to use [$("#treeDiv1").scrollTop($("#" devicesSelect.selectNodeId).offset().top-200);] , although it is effective, when there are too many nodes on the same layer, it still cannot enter the visible area. I deeply suspect that it is because the tree has not been expanded at this time, so I used animation, which is a rogue move.

The author’s last words: If there are any errors in this article, please point it out. I will be very grateful. . . .

The above content is the entire description of how to solve the bug that occurs when ztree cannot enter the visible area when acquiring selected nodes. I hope you like it.