1.2.12 • Published 4 years ago

react-graceful-image-plus v1.2.12

Weekly downloads
-
License
MIT
Repository
github
Last release
4 years ago

React Graceful Image

An image component for gracefully dealing with image errors, by providing optional lazy loading, optional placeholder and configurable retries on failure. Particularly useful in situations where your application might be used in poor signal areas such as when travelling on a train, a bus or a car.

Example

  1. Default browser behaviour when image fails due to bad signal
  2. With react-graceful-image placeholder
  3. With react-graceful-image disabled placeholder
  4. With react-graceful-image retries - if the image fails to load, the package will gracefully re-attempt loading the image again

(note: these are not mutually exclusive, for example the default behaviour makes use of both 2 & 4 together.)

Installation

npm install --save react-graceful-image

Basic Usage

import React, { Component } from "react";
import Image from "react-graceful-image";

class YourComponent extends Component {
  render() {
    return (
      <Image
        src="path_to_image"
        width="300"
        height="300"
        alt="My awesome image"
      />
    );
  }
}

Default Behaviour

  1. Render an SVG placeholder - if environment doesn't support SVG, then avoid rendering the placeholder
  2. Check if placeholder is within the visible viewport - if so then load the image
  3. If image loads successfully - display the image by fading it in
  4. If image fails to load - retry loading the image starting with a 2 second delay and doubling it with every retry (by default retry stops after 8 tries)

Prop Options

PropDescriptionDefaultType
srcImage url / pathNonestring
srcSetOne or more Image urls / paths and their sizesNonestring
widthImage widthNonestring
heightImage heightNonestring
classNameImage class nameNonestring
altImage description"Broken image placeholder"string
styleImage stylesNoneobject
placeholderColorPlaceholder's color"#eee"string
noPlaceholderTurn off placeholder renderingfalsebool
retryRetry algorithm's configuration, consisting of count, delay and accumulate{count: 8, delay: 2, accumulate: 'multiply'}object
noRetryTurn off re-tryingfalsebool
noLazyLoadTurn off lazy loadingfalsebool

Retry

You can modify the default retry algorithm by supplying a retry prop consisting of 3 properties: count, delay and accumulate:

  • count specifies the number of times you want to retry
  • delay specifies the delay between retries (in seconds)
  • accumulate specifies how the delay should increase with each retry, possible values: "multiply" (default), "add" or false (false can also be represented by simply omitting this property)

Accumulate

  • accumulate: "multiply" will multiply delay after each retry by the given delay value, i.e. if delay: 2 is given then 1st retry will be in 2 seconds, 2nd retry will be in 4 seconds, 3rd retry will be in 8 seconds, 4th retry will be in 16 seconds etc.
  • accumulate: "add" will increment delay after each retry by the given delay value, i.e. if delay: 2 is given then 1st retry will be in 2 seconds, 2nd retry will be in 4 seconds, 3rd retry will be in 6 seconds, 4th retry will be in 8 seconds, etc.
  • accumulate: "false" will keep the delay constant between retries, i.e. if delay: 2 is given then retry will run every 2 seconds

Examples

1: Below code snippet will display a light grey (default) SVG placeholder, if it is within the visible viewport then it will load the actual given image and fade it in once it is done loading. If loading the image fails, then it will retry loading the image again for a maximum of 10 times, with a fixed 2 second delay between each try.

import React, { Component } from "react";
import Image from "react-graceful-image";

class YourComponent extends Component {
  render() {
    return (
      <Image
        src="path_to_image"
        width="250"
        height="250"
        style={{ padding: "20px" }}
        alt="My awesome image"
        retry={{ count: 10, delay: 2 }}
      />
    );
  }
}

2: Below code snippet will display a blue SVG placeholder, if it is within the visible viewport then it will load the actual given image and fade it in once it is done loading. If loading the image fails, then it will retry loading the image again for a maximum of 8 times, with initial delay of 2 seconds, which will then increase to 4 seconds, then to 8 seconds, then to 16 seconds, and so on (default retry configuration).

import React, { Component } from "react";
import Image from "react-graceful-image";

class YourComponent extends Component {
  render() {
    return (
      <Image
        src="path_to_image"
        className="content-image"
        alt="My awesome image"
        placeholderColor="#0083FE"
      />
    );
  }
}

3: Below code snippet will display a light grey (default) SVG placeholder, if it is within the visible viewport then it will load the actual given image and fade it in once it is done loading. If loading the image fails, then it will retry loading the image again for a maximum of 15 times, with initial delay of 3 seconds which will then increase to 6 seconds, then to 9 seconds, then to 12 seconds, and so on.

import React, { Component } from "react";
import Image from "react-graceful-image";

class YourComponent extends Component {
  render() {
    return (
      <Image
        src="path_to_image"
        width="150"
        height="150"
        style={{ padding: "20px" }}
        alt="My awesome image"
        retry={{ count: 15, delay: 3, accumulate: "add" }}
      />
    );
  }
}