image-progress

image-progress

A wrapper for loading image via XHR and dispatching progress events.

How to use

1. Install the plugin.

With npm:

npm i image-progress --save

With Component(1):

component install ayamflow/image-progress

2. Use

var Progress = require('image-progress');

var img = new Progress('test-img.png');

img.on('error', function(event) {
    console.log('there has been an error', event);
});

img.on('progress', function(event) {
    console.log('The image is ' + event.progress * 100 + '% loaded !', event.loaded, event.total, event.progress);
});

img.on('complete', function(event) {
    console.log('The image is loaded.');
});

img.on('start', function(event) {
    console.log('The image with URL ' + event.url + ' has started loading');
});

img.load();

By default, the event.progress only has 2 decimals. You can set the number of decimals by passing the leading property as an instanciation option.

Methods

• new Progress(url, params)

url: the URL for the image you want to load.

params: the params hash is used if you need to store & retrieve any property on the start & complete events. You can also pass different options there (see the options section below).

• load()

Starts the loading. It will fire a start event.

• destroy()

Removes all internal & external listeners, and clears the XHR object.

By default, this method is called after the complete and/or error events are triggered. you can disable this behavior by passing the autoclear: false as an instanciation option.

Instanciation options

• onStart, onError, onProgress, onComplete (default: null)

Callbacks to be called when the appropriate events are fired.

• autoload (default: false)

Wether the loading should start automatically on instanciation. If you set it to true, be sure to also pass onProgress/onComplete callbacks as well or you won't be able to listen for completion.

• leading (default: 2)

The number of decimals in the event.progress property.

• autoclear (default: true)

Set wether the destroy method should be automatically called after a complete or error event.

• jsonp (default: false)

Uses jsonp in order to bypass CORS restrictions

Events

• start: fired when the loading starts. The event contains a reference to the options hash, as well as the url.
• progress: fired each time the XHR request updates. The event has 3 properties: loaded, total and progress.
• complete': fired when the loading is complete. The event contains a reference to the options hash, as well as the url.
• error: fired when a network-related error is raised.

Properties

• total: the total bytes to load

• loaded: the loaded bytes loaded

• progress: the loading progress, between 0 and 1