Loadic

Lightweight assets loader with retina support. Use it for loading images, styles and scripts.

Install

Bower: bower install loadic

Npm: npm install loadic

Usage

ES6 modules

from 'loadic' import Loader;
 
let loader = new Loader({
    common: [
        'images/example1.jpg*',
        'images/example3.bmp!',
        'css/external.css'
    ],
    dpiDependent: [
        'images/example2.jpg'
    ]
});
 
loader.onProgress = (progress) => {
    console.log(`loaded: ${progress}%`);
}
 
loader.onComplete = () => {
    console.log('complete');
}
 

AMD enviroment

require(['loadic/loadic.amd'], function(Loader){
 
    var loader = new Loader.default({
        common: [
            'images/example1.jpg*',
            'images/example3.bmp!',
            'css/external.css'
        ],
        dpiDependent: [
            'images/example2.jpg'
        ]
    });
    
    // etc...
});

No modules

var loader = new loadic({
    common: [
        'images/example1.jpg*',
        'images/example3.bmp!',
        'css/external.css'
    ],
    dpiDependent: [
        'images/example2.jpg'
    ]
});
 
// etc...

Options

baseUrl

Base url for assets. Will be prepended to each asset location that does not starts with "http". Default: ''

common

Array of assets urls. Default: []

dpiDependent

Array of dpi dependent images which have high resolution versions. Default: []

! suffix

Append ! suffix to file name, if it is required for your project. For example: 'scripts/core.js!'. This files will be loaded first. Also, if timeout option is set, it does not fire onComplete on expiration, while required resources are loaded.

* suffix

Append * suffix to file name, if you prefer to use XHR for this resource. It's very usefull when you preloading media (video, audio etc). For example: 'scripts/video.mp4*'. This prefix mark current file as required and load resource via XHR. Loaded result available in data field of resource as ArrayBuffer.

timeout

When user has slow connection, he can bounce due to the long loading screen. Experiment with this option and network throttling to achieve the best user experience. When timeout expires, onComplete callback will be fired and you can minimize progress bar. Default: false

highDpiSuffix

Suffix which will be appended to dpi dependent images in case of high resolution screen detection. Default: '@2x'

highDpiCondition

This function is called to determine whether to use high definition resources or standard definition resources. Default: window.devicePixelRatio > 1

Instance properties

progress

Loader progress. Integer 0..100

resources

Array of resourses:

[
    {
        src: '//url-to-file',
        required: true, // set to true when you use ! or * suffixes
        loaded: true,
        xhr: true, // set to true when you use * suffix
        data: [ArrayBuffer] // available if use XHR preload only
    }, ...
]

License

MIT