How to create an Ellipse with crosshair cursor on hover over objects using FabricJS?

FabricJSJavascriptHTML5 Canvas

In this tutorial, we are going to create an Ellipse with a crosshair cursor on hover over objects using FabricJS. crosshair is one of the native cursor styles available which can be used in the FabricJS canvas too. FabricJS provides various types of cursors like default, all-scroll, crosshair, col-resize, row-resize etc which are reusing the native cursor underhood. The hoverCursor property sets the style of the cursor when hovered over a canvas object.

Syntax

new fabric.Ellipse({ hoverCursor: String }: Object

Parameters

  • options (optional) − This parameter is an Object which provides additional customizations to our ellipse. Using this parameter color, cursor, stroke width and a lot of other properties can be changed related to the object of which hoverCursor is a property.

Options Keys

  • hoverCursor − This property accepts a String which determines the name of the cursor to be used on hovering over the canvas object. By using this property, we can set the default cursor value when hovering over the ellipse object on the canvas.

Example 1

Passing the hoverCursor Key to the class

By default, when we hover over an ellipse object in the canvas, the cursor type is move. Let's see a code to create a canvas with a crosshair cursor while hovering over an ellipse object in FabricJS.

<!DOCTYPE html>
<html>
   <head>
      <!-- Adding the Fabric JS Library-->
      <script src="https://cdnjs.cloudflare.com/ajax/libs/fabric.js/510/fabric.min.js"></script>
      </head>

   <body>
      <h2>Creating an ellipse with crosshair cursor on hover over objects using FabricJS?</h2>
      <p> Hover the mouse over the ellipse to see the crosshair cursor.</p>
      <canvas id="canvas"></canvas>

      <script>
         // Initiate a canvas instance
         var canvas = new fabric.Canvas("canvas");

         // Initiate an ellipse instance
         var ellipse = new fabric.Ellipse({
            left: 100,
            top: 100,
            fill: "#a2006d",
            rx: 80,
            ry: 50,
            stroke: "#c154c1",
            strokeWidth: 5,
            hoverCursor: "crosshair",
         });

         // Adding it to the canvas
         canvas.add(ellipse);
         canvas.setWidth(document.body.scrollWidth);
         canvas.setHeight(250);
      </script>
   </body>
</html>

Example 2

Proof that hoverCursor applies to a specific object

In this example, we are passing the hoverCursor key to the ellipse class which means that the hoverCursor property would not be changed for every object in the canvas. Changes will only occur for that single object.

<!DOCTYPE html>
<html>
   <head>
      <!-- Adding the Fabric JS Library-->
      <script src="https://cdnjs.cloudflare.com/ajax/libs/fabric.js/510/fabric.min.js"></script>
   </head>

   <body>
      <h2>Creating an Ellipse with crosshair cursor on hover over objects using FabricJS?</h2>
      <p>Hover the mouse over the left ellipse to see the crosshair cursor. We haven't applied the hoverCursor property to the right ellipse. </p2>
      <canvas id="canvas"></canvas>

      <script>
         // Initiate a canvas instance
         var canvas = new fabric.Canvas("canvas");

         // Initiate an ellipse instance
         var ellipseOne = new fabric.Ellipse({
            left: 90,
            top: 100,
            fill: "white",
            rx: 80,
            ry: 50,
            stroke: "#c154c1",
            strokeWidth: 5,
            hoverCursor: "crosshair",
         });

         // Initiate another ellipse instance
         var ellipseTwo = new fabric.Ellipse({
            left: 280,
            top: 100,
            fill: "#a2006d",
            rx: 80,
            ry: 50,
         });

         // Add them to the canvas
         canvas.add(ellipseOne);
         canvas.add(ellipseTwo);
         canvas.setWidth(document.body.scrollWidth);
         canvas.setHeight(250);
      </script>
   </body>
</html>
raja
Updated on 24-May-2022 09:05:15

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