Hover multi line tree node in EJ2 JavaScript Treeview control

2 Nov 202314 minutes to read

This section demonstrates how to hover and select a multi-line tree node. Here, you can set the row height (element class: e-fullrow) to be the same as the row content (element class: e-text-content)

index.js

/**
 * Hovering multiline tree sample
 */

// Hierarchical data source for TreeView component
 var hierarchicalData = [
     {
            id: 1, name: 'Web Control sWeb ControlsWeb ControlsWeb ControlsWeb ControlsWeb ControlsWeb ControlsWeb Controls', expanded: true,
            child: [
                {
                    id: 2, pid: 1, name: 'CalendarCalendarCalendarCalendarCalendarCalendarCalendarCalendarCalendarCalendarCalendarCalendarCalendar', checked: true, child: [
                        { id: 7, pid: 2, name: 'Constructors' },
                        { id: 8, pid: 2, name: 'Properties' },
                        { id: 9, pid: 2, name: 'Methods' },
                        { id: 10, pid: 2, name: 'Events' }
                    ]
                },
                {
                    id: 3, pid: 1, name: 'Data Grid', child: [
                        { id: 11, pid: 3, name: 'Constructors' },
                        { id: 12, pid: 3, name: 'Fields' },
                        { id: 13, pid: 3, name: 'Properties' },
                        { id: 14, pid: 3, name: 'Methods' },
                        { id: 15, pid: 3, name: 'Events' }
                    ]
                },
                {
                    id: 4, pid: 1, name: 'DropDownList', child: [
                        { id: 16, pid: 4, name: 'Constructors' },
                        { id: 17, pid: 4, name: 'Properties' },
                        { id: 18, pid: 4, name: 'Methods' }
                    ]
                },
                {
                    id: 5, pid: 1, name: 'Menu', child: [
                        { id: 19, pid: 5, name: 'Constructors' },
                        { id: 20, pid: 5, name: 'Fields' },
                        { id: 21, pid: 5, name: 'Properties' },
                        { id: 22, pid: 5, name: 'Methods' },
                        { id: 23, pid: 5, name: 'Events' }
                    ]
                },
            ]
        },
        {
            id: 24, name: 'Web Controls',
            child: [
                {
                    id: 25, pid: 24, name: 'Calendar', checked: true, child: [
                        { id: 26, pid: 25, name: 'Constructors' },
                        { id: 27, pid: 25, name: 'Properties' },
                        { id: 28, pid: 25, name: 'Methods' },
                        { id: 29, pid: 25, name: 'Events' }
                    ]
                },
                {
                    id: 30, pid: 24, name: 'Data Grid', child: [
                        { id: 31, pid: 30, name: 'Constructors' },
                        { id: 32, pid: 30, name: 'Fields' },
                        { id: 33, pid: 30, name: 'Properties' },
                        { id: 34, pid: 30, name: 'Methods' },
                        { id: 35, pid: 30, name: 'Events' }
                    ]
                }
            ]
        }
];
var tree1 = new ej.navigations.TreeView({
    fields: { dataSource:hierarchicalData , id: 'id', text: 'name', child: 'child' },
    nodeSelecting: onselect,
    cssClass: "customTree"
});
tree1.appendTo('#tree');

// Triggers on mouse hover/keydown event
 ['mouseover','keydown'].forEach( evt => 
      document.getElementById("tree").addEventListener(evt, (event)=>{setHeight(event.target); }));
    
     // Triggers on node selection
    function onSelect(arg) {
      setHeight(arg.node);
    }

     // Sets e-fullrow to be the same as e-text-content
    function setHeight(element) {
      if(tree1.fullRowSelect) {
        if(element.classList.contains("e-treeview")) {
          element = element.querySelector(".e-node-focus").querySelector(".e-fullrow");
        }
        else if(element.classList.contains("e-list-parent")) {
          element = element.querySelector(".e-fullrow");
        }
        else if(element.classList.value != ("e-fullrow") && element.closest(".e-list-item")) {        
          element = element.closest(".e-list-item").querySelector(".e-fullrow");   
        }
        if(element.nextElementSibling)
          element.style.height = element.nextElementSibling.offsetHeight +"px";        
      }
    }

index.html

<!DOCTYPE html><html lang="en"><head>
    <title>Essential JS 2 for TreeView </title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="Essential JS 2 for TreeView UI Control">
    <meta name="author" content="Syncfusion">
    <link href="index.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/25.1.35/ej2-base/styles/material.css" rel="stylesheet">
      <link href="https://cdn.syncfusion.com/ej2/25.1.35/ej2-inputs/styles/material.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/25.1.35/ej2-navigations/styles/material.css" rel="stylesheet">
    
    
<script src="https://cdn.syncfusion.com/ej2/25.1.35/dist/ej2.min.js" type="text/javascript"></script>
<script src="https://cdn.syncfusion.com/ej2/syncfusion-helper.js" type ="text/javascript"></script>
</head>

<body>
    
    <div id="container">
        <div id="treeparent">
            <div id="tree"></div>
        </div>
    </div>



<script>
var ele = document.getElementById('container');
if(ele) {
  ele.style.visibility = "visible";
}   
      </script>
<script src="index.js" type="text/javascript"></script>
</body></html>

index.css

#container {
    visibility: hidden;
}

#loader {
  color: #008cff;
  height: 40px;
  width: 30%;
  position: absolute;
  font-family: 'Helvetica Neue','calibiri';
  font-size: 14px;
  top: 45%;
  left: 45%;
}

#treeparent {
    display: block;
    max-width: 350px;
    max-height: 350px;
    margin: auto;
    overflow: auto;
    border: 1px solid #dddddd;
    border-radius: 3px;
}

.customTree li .e-list-text{
  white-space: normal;
  word-break: break-all;
}