Positioning a node in EJ2 JavaScript Diagram control

15 Dec 20247 minutes to read

Position

  • Position of a node is controlled by using its offsetX and offsetY properties. By default, these offset properties represent the distance between the origin of the diagram’s page and node’s center point.

  • You may expect this offset values to represent the distance between page origin and node’s top-left corner instead of center. The Pivot property helps to solve this problem. Default value of node’s pivot point is (0.5, 0.5), that means center of the node.

  • The size of the node can be controlled by using its width and height properties.

  • Rotation of a node is controlled by using its rotateAngle property.

The following table illustrates how pivot relates offset values with node boundaries.

Pivot Offset
(0.5,0.5) offsetX and offsetY values are considered as the node’s center point.
(0,0) offsetX and offsetY values are considered as the top-left corner of the node.
(1,1) offsetX and offsetY values are considered as the bottom-right corner of the node.

The following code illustrates how to change the pivot value.

var node = {
    // Position of the node
    offsetX: 250,
    offsetY: 250,
    // Size of the node
    width: 100,
    height: 100,
 style: { fill: '#6BA5D7', strokeColor: 'white' },
    pivot: {x: 0, y: 0}
        };

// initialize Diagram component

var diagram = new ej.diagrams.Diagram({
    width: '100%', height: '600px', nodes: [node]
    }, '#element');

diagram.select([diagram.nodes[0]]);
<!DOCTYPE html><html lang="en"><head>
    <title>EJ2 Diagram</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="Typescript UI Controls">
    <meta name="author" content="Syncfusion">
    <link href="index.css" rel="stylesheet">
    
    <link href="https://cdn.syncfusion.com/ej2/28.2.3/ej2-base/styles/material.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/28.2.3/ej2-buttons/styles/material.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/28.2.3/ej2-popups/styles/material.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/28.2.3/ej2-splitbuttons/styles/material.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/28.2.3/ej2-diagrams/styles/material.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/28.2.3/ej2-navigations/styles/fabric.css" rel="stylesheet">
    
<script src="https://cdn.syncfusion.com/ej2/28.2.3/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="element"></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>

Minimum and maximum size for nodes.

The minWidth and minHeight properties of node allows you to control the minimum size of the node while resizing. Similarly, the maxWidth and maxHeight properties of node allows you to control the maximum size of the node while resizing.

var node = {
    // Position of the node
    offsetX: 250,
    offsetY: 250,
    // Size of the node
    width: 100,
    height: 100,
    visible: true,
    minWidth:50,
    minHeight:50,
    maxWidth:200,
    maxHeight:200,
    style: { fill: '#6AA8D7'},
    // Text(label) added to the node
        };
    

// initialize Diagram component

var diagram = new ej.diagrams.Diagram({
    width: '100%', height: '600px', nodes: [node]
    }, '#element');
<!DOCTYPE html><html lang="en"><head>
    <title>EJ2 Diagram</title>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta name="description" content="Typescript UI Controls">
    <meta name="author" content="Syncfusion">
    <link href="index.css" rel="stylesheet">
    
    <link href="https://cdn.syncfusion.com/ej2/28.2.3/ej2-base/styles/material.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/28.2.3/ej2-buttons/styles/material.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/28.2.3/ej2-popups/styles/material.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/28.2.3/ej2-splitbuttons/styles/material.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/28.2.3/ej2-diagrams/styles/material.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/28.2.3/ej2-navigations/styles/fabric.css" rel="stylesheet">
    
<script src="https://cdn.syncfusion.com/ej2/28.2.3/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="element"></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>

MinSize-MaxSize GIF