Annotation events.

There are some events which will trigger while interacting with annotation.

KeyDown.
KeyUp.
DoubleClick.
TextEdit.

KeyDown event

The keyDown event is triggered whenever any key is pressed. The following example shows how to capture the keyDown event and modify the fill color of a node on each key press:

index.js
index.html
var node = {
  // Position of the node
  offsetX: 250,
  offsetY: 250,
  // Size of the node
  width: 100,
  height: 100,
  style: { fill: '#6BA5D7', strokeColor: 'white' },
  annotations: [{ content: 'Center' }],
};
let color = 'pink';
// initialize Diagram component
var diagram = new ej.diagrams.Diagram(
  {
    width: '100%',
    height: '600px',
    nodes: [node],
    keyDown: function (args) {
      //customize
      if (color === 'pink') {
        color = 'yellow';
        diagram.nodes[0].style.fill = 'red';
        diagram.dataBind();
      } else {
        color = 'pink';
        diagram.nodes[0].style.fill = 'pink';
        diagram.dataBind();
      }
    },
  },
  '#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/ej2/33.2.3/ej2-base/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-buttons/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-popups/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-splitbuttons/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-diagrams/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-navigations/styles/tailwind3.css" rel="stylesheet">
    
<script src="https://cdn.syncfusion.com/ej2/33.2.3/dist/ej2.min.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>

KeyUp event

The keyUp event is triggered whenever we press and release any key. The following example shows how to capture the keyUp event and modify the fill color of a node on each key press:

index.js
index.html
var node = {
  // Position of the node
  offsetX: 250,
  offsetY: 250,
  // Size of the node
  width: 100,
  height: 100,
  style: { fill: '#6BA5D7', strokeColor: 'white' },
  annotations: [{ content: 'Center' }],
};
// initialize Diagram component
let color = 'pink';
var diagram = new ej.diagrams.Diagram(
  {
    width: '100%',
    height: '600px',
    nodes: [node],
    keyUp: function (args) {
      //customize
      if (color === 'pink') {
        color = 'yellow';
        diagram.nodes[0].style.fill = 'red';
        diagram.dataBind();
      } else {
        color = 'pink';
        diagram.nodes[0].style.fill = 'pink';
        diagram.dataBind();
      }
    },
  },
  '#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/ej2/33.2.3/ej2-base/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-buttons/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-popups/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-splitbuttons/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-diagrams/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-navigations/styles/tailwind3.css" rel="stylesheet">
    
<script src="https://cdn.syncfusion.com/ej2/33.2.3/dist/ej2.min.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>

Double click event

The doubleClick event is triggered when you double-click on a node, connector, or the diagram surface. Double-clicking on a diagram element activates the annotation editing mode. The following code example shows how to capture the doubleClick event:

index.js
index.html
var node = {
  // Position of the node
  offsetX: 250,
  offsetY: 250,
  // Size of the node
  width: 100,
  height: 100,
  style: { fill: '#6BA5D7', strokeColor: 'white' },
  annotations: [{ content: 'Center' }],
};
// initialize Diagram component
let color = 'pink';
var diagram = new ej.diagrams.Diagram(
  {
    width: '100%',
    height: '600px',
    nodes: [node],
    doubleClick: function (args) {
      console.log(args.name);
    },
  },
  '#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/ej2/33.2.3/ej2-base/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-buttons/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-popups/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-splitbuttons/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-diagrams/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-navigations/styles/tailwind3.css" rel="stylesheet">
    
<script src="https://cdn.syncfusion.com/ej2/33.2.3/dist/ej2.min.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>

TextEdit event

The textEdit event triggers when you finish editing the annotation text and the focus is removed from the annotation text.

index.js
index.html
var node = {
  // Position of the node
  offsetX: 250,
  offsetY: 250,
  // Size of the node
  width: 100,
  height: 100,
  style: { fill: '#6BA5D7', strokeColor: 'white' },
  annotations: [{ content: 'Center' }],
};
// initialize Diagram component
var diagram = new ej.diagrams.Diagram(
  {
    width: '100%',
    height: '600px',
    nodes: [node],
    textEdit: function (args) {
      console.log(args.name);
    },
  },
  '#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/ej2/33.2.3/ej2-base/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-buttons/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-popups/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-splitbuttons/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-diagrams/styles/tailwind3.css" rel="stylesheet">
    <link href="https://cdn.syncfusion.com/ej2/33.2.3/ej2-navigations/styles/tailwind3.css" rel="stylesheet">
    
<script src="https://cdn.syncfusion.com/ej2/33.2.3/dist/ej2.min.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>

You can prevent adding new text to the annotation by setting the cancel property of textEdit to true.

textEdit: function (args) {
    // Prevents any new content from being added to the annotation
    args.cancel = true;
  },

Selection change event

The selectionChange event is triggered when an annotation of a node or connector is selected in the diagram.

You can prevent selection by setting the cancel property of SelectionChangeEventArgs to true, as shown in the code snippet below.

selectionChange: function (args) {
  if (args.state === 'Changing') {
    // Prevents selection
    args.cancel = true;
  }
}

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