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  • How to use go language to implement smart contract functions
    How to use go language to implement smart contract functions
    How to use Go language to implement the functions of smart contracts. Smart contracts are a form of contract based on blockchain technology. It runs on the blockchain and can automatically execute the agreements in it. In recent years, smart contracts have received widespread attention and application and can be used to implement automated business logic in a variety of scenarios. This article will introduce how to use Go language to implement smart contract functions and provide corresponding code examples. 1. Blockchain development library in Go language. Before using Go language to develop smart contracts, we need to choose a suitable blockchain development library. Head
    Golang . fabric 2306 2023-08-26 10:19:44
  • FabricJS - How to create an instance of fabric.Image from its object representation?
    FabricJS - How to create an instance of fabric.Image from its object representation?
    In this tutorial, we will show you how to create an instance of Fabric.Image from its object representation using FabricJS. We can create an Image object in the following way to create an instance of fabric.Image. Since it is one of the basic elements of FabricJS, we can also easily customize it by applying properties such as angle, opacity, etc. To create an instance of fabric.Image from its object representation, we use the fromObject method. Syntax fromObject(object:Object,callback:function) Parameter object-This parameter accepts an object that represents the
    JS Tutorial . fabric 918 2023-08-25 21:17:14
  • FabricJS - Check if cache is dirty and polygon requires renderer?
    FabricJS - Check if cache is dirty and polygon requires renderer?
    We can create Polygon objects by creating an instance of fabric.Polygon. A polygon object can be characterized as any closed shape consisting of a set of connected straight line segments. Since it is one of the basic elements of FabricJS, we can also easily customize it by applying properties such as angle, opacity, etc. We can use the isCacheDirty method to check if the cache is dirty and if a renderer is needed. This method checks if the cache is dirty, letting FabricJS know that something in the canvas has changed and needs to be re-rendered. Syntax isCacheDirty(skipCanvas:Boolean) Parameter skipCanvas (optional) - this parameter
    JS Tutorial . fabric 1194 2023-08-25 15:17:10
  • How to add a dashed stroke to a rectangle using FabricJS?
    How to add a dashed stroke to a rectangle using FabricJS?
    In this tutorial, we will learn how to add a dashed stroke to a rectangle using FabricJS. Rectangle is one of the various shapes provided by FabricJS. In order to create a rectangle, we have to create an instance of the Fabric.Rect class and add it to the canvas. The StrokeDashArray property allows us to specify a dash pattern for the object's strokes. Syntax newfabric.Rect({strokeDashArray:Array}:Object) Parameter options (optional) - This parameter is an object that provides additional customization to our rectangle. Using this parameter, you can change the color, light, and
    JS Tutorial . fabric 1103 2023-08-25 12:29:09
  • How to set the vertical scale factor of a rectangle using FabricJS?
    How to set the vertical scale factor of a rectangle using FabricJS?
    In this tutorial, we will learn how to set the vertical scale factor of a rectangle using FabricJS. Rectangle is one of the various shapes provided by FabricJS. In order to create a rectangle, we must create an instance of the Fabric.Rect class and add it to the canvas. Just like we can specify the position, color, opacity, and size of a rectangular object in the canvas, we can also set the vertical scale of the rectangular object. This can be done by using the scaleY property. Syntax newfabric.Rect({scaleY:Number}:Object) Parameter Options (optional) - This parameter is an object that provides additional customization to our rectangle. Using this parameter, you can change the
    JS Tutorial . fabric 1446 2023-08-25 12:25:09
  • FabricJS - How to set the position of a Line object relative to the origin?
    FabricJS - How to set the position of a Line object relative to the origin?
    In this tutorial, we will learn how to set the position of a Line object relative to its origin using FabricJS. Line element is one of the basic elements provided in FabricJS. It is used to create straight lines. Since line elements are geometrically one-dimensional and contain no interiors, they are never filled. We can create a line object by creating an instance of fabric.Line, specifying the x and y coordinates of the line and adding it to the canvas. To set the position of a Line object relative to the origin, we use the setPositionByOrigin method. Syntax setPositionByOrigin(pos:fabric.Point,originX:S
    JS Tutorial . fabric 1513 2023-08-25 12:13:08
  • How to set the padding of a circle using FabricJS?
    How to set the padding of a circle using FabricJS?
    In this tutorial, we will learn how to set the padding of a circle using FabricJS. Circle is one of the various shapes provided by FabricJS. In order to create a circle, we have to create an instance of the Fabric.Circle class and add it to the canvas. Just as we can specify the position, color, opacity, and size of a circular object within the canvas, we can also set the fill of the circular object. This can be done using the padding attribute. Syntax newfabric.Circle({padding:Number}:Object) Parameter options (optional) - This parameter is an object that provides additional customization for our circle. Using this parameter, you can change the
    JS Tutorial . fabric 1132 2023-08-25 10:45:05
  • How to get the scaled width of text using FabricJS
    How to get the scaled width of text using FabricJS
    In this tutorial, we will learn how to get the scaled width of text using FabricJS. We can display text on the canvas by adding an instance of Fabric.Text. It not only allows us to move, scale and change the size of the text, but also provides additional features such as text alignment, text decoration, line height, which can be obtained through the properties textAlign, underline and lineHeight respectively. We can also find the scaled width of an object using the getScaledWidth method. Syntax getScaledWidth() Example 1 Using getScaledWidth method Let’s look at a code example to see how to use getSca
    JS Tutorial . fabric 857 2023-08-25 09:13:02
  • How to straighten IText objects using FabricJS?
    How to straighten IText objects using FabricJS?
    In this tutorial, we will learn how to straighten IText objects using FabricJS. The IText class was introduced in FabricJS version 1.4, which extends Fabric.Text and is used to create IText instances. IText instances allow us to freely select, cut, paste or add new text without additional configuration. There are also various supported key combinations and mouse/touch combinations to make text interactive that are not available in Text. However, Textbox based on IText allows us to resize the text rectangle and wrap it automatically. This is not the case for IText, as the height does not adjust based on line breaks. We can manipulate I by using various properties
    JS Tutorial . fabric 1524 2023-08-25 09:09:06
  • How to set the opacity of an image using FabricJS?
    How to set the opacity of an image using FabricJS?
    In this tutorial, we will learn how to set the opacity of an image using FabricJS. We can create an Image object by creating an instance of fabric.Image. Since it is one of the basic elements of FabricJS, we can also easily customize it by applying properties such as angle, opacity, etc. To set the opacity of an image, we use the opacity property. Syntax newfabric.Image(element:HTMLImageElement|HTMLCanvasElement|HTMLVideoElement|String,{opacity:Number}:Object
    JS Tutorial . fabric 1121 2023-08-24 23:53:10
  • FabricJS - How to center a Line object in the current viewport of the canvas?
    FabricJS - How to center a Line object in the current viewport of the canvas?
    In this tutorial, we will learn how to center a Line object horizontally and vertically in the current viewport of the canvas using FabricJS. Line element is one of the basic elements provided in FabricJS. It is used to create straight lines. Since line elements are geometrically one-dimensional and contain no interiors, they are never filled. We can create a line object by creating an instance of Fabric.Line, specifying the x and y coordinates of the line, and adding it to the canvas. To center the Line object on the current viewport of the canvas, we use the viewportCenter method. Syntax viewportCenter():default appearance example of fabric.ObjectLine object let me
    JS Tutorial . fabric 813 2023-08-24 22:41:05
  • How to set animation duration in text using FabricJS?
    How to set animation duration in text using FabricJS?
    In this tutorial, we will learn how to set the duration of animated text using FabricJS. We can display text on the canvas by adding an instance of Fabric.Text. It not only allows us to move, scale and change the size of the text, but also provides additional features such as text alignment, text decoration, line height, which can be obtained through the properties textAlign, underline and lineHeight respectively. Similarly, we can also use the duration attribute to change the duration of animated text. Syntax animate(property:String|Object,value:Number|Object,{durat
    JS Tutorial . fabric 1239 2023-08-24 22:17:09
  • How to disable centered scaling of a rectangle using FabricJS?
    How to disable centered scaling of a rectangle using FabricJS?
    In this tutorial, we will learn how to disable centered scaling of a rectangle using FabricJS. Rectangle is one of the various shapes provided by FabricJS. In order to create a rectangle, we need to create an instance of the fabric.Rect class and add it to the canvas. When scaling via a controller, set the centeredScaling property to true to use the center as the starting point for the object's transformation. Syntax newfabric.Rect({centeredScaling:Boolean}:Object)ParametersOptions(optional)−ThisparameterisanObject
    JS Tutorial . fabric 1342 2023-08-24 20:53:07
  • How to find the complexity of an Image instance using FabricJS?
    How to find the complexity of an Image instance using FabricJS?
    In this tutorial, we will learn how to find the complexity of Image instances using FabricJS. We can create an Image object by creating an instance of fabric.Image. Since it is one of the basic elements of FabricJS, we can also easily customize it to apply attributes such as angle, opacity, etc. To find the complexity of an image, for example, we use the complexity method. This method will return 1 if the current object is inherited directly from the base class, not from a subclass. Syntax complexity():Number Example using complexity method Let us look at a code example to see the complexity of getting an Image instance using the recorded output when using the complexity method. remove
    JS Tutorial . fabric 1202 2023-08-24 20:45:06
  • How to set vertical origin of text transformation using FabricJS?
    How to set vertical origin of text transformation using FabricJS?
    In this tutorial, we will learn how to set the vertical origin of text transformations using FabricJS. We can display text on the canvas by adding an instance of Fabric.Text. It not only allows us to move, scale and change the size of the text, but also provides additional features such as text alignment, text decoration, line height, which can be obtained through the properties textAlign, underline and lineHeight respectively. Similarly, we can also use the originY attribute to set the vertical origin of the transformation. Syntax newfabric.Text(text:String,{originY:String}:Object) parameter text-this parameter
    JS Tutorial . fabric 1610 2023-08-24 19:49:08

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