How to drop the folder items into another folder in a tree after confirmation dialog?

I have a modelbox for confirmation dialog.When I perform drag&drop for an item/folder from source to target, if that target folder has existed with the same name I am showing one modelbox window with continue/cancel button .But the problem is that the source folder/item is dropped into target one before the model box is appeared.But I need the folder/item should be dropped after continue button is clicked.

When i use the “move()” to drop the item into specified location of subchild, it drops to into the outside of the root folder.How can i drop the item into specified location i.e…item of subchild of the root…How can I traverse to the specified location of “folder”?..

                     webix.ui({
                     header: "Folders",
                      body: {
                     view: "tree",
                      id: "folder",
                       data: treeData,
                       drag: true,
                        activeTitle: true,
                      select: true,
                       multiselect: true,
                                     
                           on: {

                       onBeforeDrop: function(context, native_event){
                         context.parent = context.target;
                        var targetId = (context.target);
                         var parentId = (context.parent);                                               
                       var doDrag = false,haveSameFileName = false;            
                           console.log("parent: "+parentId);                
                           var currentText = this.getItem(context.source).value;
            
        
                             $$("folder").data.eachChild(parentId, function(obj){

                                 if(currentText === obj.value) {
            
                                       console.log("child: "+ obj.value);
                                       haveSameFileName = true;
                                                 } 
                                             });
                            if(haveSameFileName)
                                     {
                        console.log("Same File Name"+haveSameFileName);    
                         webix.modalbox({
                       title:"Confirmation Dialog",
                     buttons:["Continue", "Rename", "Cancel"],
                     text:"Any content here",
                      width: "500px",
                    callback: function(result){
                      switch(result){

                       case "0":
                                    var sid=(context.source);
                              console.log("Continue");
                                   
                                  $$("folder").move(sid,0);
                               break;
               
                        case "1":
                            console.log("Rename");
                              break;                   
                      case "2":
                             doDrag = false;
                              console.log("Cancel");
                              break;                
                          }
                  }
           });
       return doDrag;
     }
     else
         {
          console.log("HII");
         return true;
        }
    } 
   return doDrag;       
   },});

Please help me with this.

Thanks in advance ):-

You need to block d-n-d ( return false from onBeforeDrop ) and if confirmation received - call move API to move folder in necessary place

http://docs.webix.com/api__treedatamove_move.html

The only modal box that can pause event execution is native confirm dialog. Any other UI may look as modal box, but will not stop javascript execution