Using Doka Image Editor with JavaScript

For a quick start use the JavaScript example project included in the product package as a guideline. It includes a normal, modal, and overlay editor example.

We can use appendEditor or appendEditors for appending the Doka Image Editor to the DOM. We can use openEditor to open the editor in a modal and use overlayEditor to render Doka Image Editor controls on top of a loaded image.

Creating an instance

appendEditor

The appendEditor method can be used to create a single instance by either passing a selector a single node. Add an extra object to pass configuration values.

import { appendEditor } from './doka.js';

// single
const editor = appendEditor('.my-editor', {
    // options here (optional)
});

appendEditors

Use appendEditors to create multiple instances by either passing a NodeList, an Array, or a query selector. We can also add an extra object to pass configuration values. The configuration values are deep cloned and supplied to each instance.

import { appendEditors } from './doka.js';

// multiple
const myEditorRefs = document.querySelectorAll('.my-editor');

const editors = appendEditors(myEditorRefs, {
    // options here (optional)
});

editors.forEach((editor) => {
    // do something with each created instance
});

openEditor

openEditor automatically creates a modal. It doesn't accept a selector or target element as the modal is added to the <body> element automatically.

The modal will automatically be shown when an image starts loading. Alternatively we can call the show and hide methods on the editor instance to manually show and hide the editor.

import { openEditors } from './doka.js';

const editor = openEditor({
    // options here (optional)
});

overlayEditor

overlayEditor automatically places the editor controls on top of the loaded image, it functions the same as appendEditor.

import { overlayEditor } from './doka.js';

const editor = overlayEditor('.my-editor', {
    // options here (optional)
});

When using this method, Doka Image Editor will automatically:

  • Update the aspect ratio of the output image with the aspect ratio of the editor itself.
  • Zoom the preview image to fit the editor container
  • Disable the main menu.
  • Disable the crop preset dropdown.
  • Disable the crop info indicator.

The overlayEditor layout mode currently only supports showing the crop plugin.

Configuring the instance

With the editor logic installed we now need to load the plugins, the locale to use, and set the imageReader which is used to load images. Without these properties the editor won't load.

Doka Image Editor doesn't set any default values or labels, while this helps keep the library size as small as possible, it also means that we have to supply the default values and properties ourselves.

Let's start with registering the plugins using the setPlugins function. We'll then load the locale objects, finally we'll set the imageReader and the default plugin properties.

Registering plugins

Doka Image Editor uses plugins to render each util view. To get started we'll load the crop plugin, the finetune plugin, and the annotate plugin.

<!DOCTYPE html>

<link rel="stylesheet" href="doka.css" />

<style>
    .my-editor {
        height: 480px;
    }
</style>

<div class="my-editor"></div>

<script type="module">
    import {
        // The method used to register the plugins
        setPlugins,

        // The plugins we want to use
        plugin_crop,
        plugin_finetune,
        plugin_annotate,
    } from 'doka.js';

    // This registers the plugins with Doka Image Editor
    setPlugins(plugin_crop, plugin_finetune, plugin_annotate);
</script>

Setting the locale object

Now we need to tell Doka Image Editor what labels and icons to use for all its UI controls. To do this we can import the English locale objects and assign them to the locale prop.

The Doka Image Editor module exports a core language file and a language file for each plugin. Currently only the English locale files are available in the package.

You can override the language files to show labels in a different language.

<!DOCTYPE html>

<link rel="stylesheet" href="doka.css" />

<style>
    .my-editor {
        height: 480px;
    }
</style>

<div class="my-editor"></div>

<script type="module">
    import {
        // The method used to register the plugins
        setPlugins,

        // The plugins we want to use
        plugin_crop,
        plugin_finetune,
        plugin_annotate,

        // The method used to render the editor
        appendEditor,

        // The main UI and plugin locale objects
        locale_en_gb,
        plugin_crop_locale_en_gb,
        plugin_finetune_locale_en_gb,
        plugin_annotate_locale_en_gb,

        // Because we use the annotate plugin we also need
        // to import the markup editor locale
        markup_editor_locale_en_gb,
    } from 'doka.js';

    // This registers the plugins with Doka Image Editor
    setPlugins(plugin_crop, plugin_finetune, plugin_annotate);

    // Merge all the locale objects
    const myLocale = {
        ...locale_en_gb,
        ...plugin_crop_locale_en_gb,
        ...plugin_finetune_locale_en_gb,
        ...plugin_annotate_locale_en_gb,
        ...markup_editor_locale_en_gb,
    };

    // Create the editor
    const doka = appendEditor('.my-editor', {
        // The image to load
        src: './my-image.jpeg',

        // Set locale
        locale: myLocale,
    });
</script>

Changing labels can be done by updating existing locale properties or by creating a custom locale object.

// Merge all the locale objects
const myLocale = {
    ...locale_en_gb,
    ...plugin_crop_locale_en_gb,
    ...plugin_finetune_locale_en_gb,
    ...plugin_annotate_locale_en_gb,
    ...markup_editor_locale_en_gb,
};

// Change label of export button to 'Save'
myLocale.labelButtonExport = 'Save';

Setting the imageReader

The imageReader property expects a list of instructions that tells Doka Image Editor how to load images.

A default image reader is exported by the JavaScript module. It can read resources of type File, Blob, Data URL, URL, HTMLCanvasElement, and HTMLImageElement. It will also automatically correct mobile photo orientation when needed.

By default Doka Image Editor can read images that are supported by the clients browser. In general these image formats are supported by all major browsers.

  • image/gif
  • image/png
  • image/jpeg
  • image/webp
  • image/bmp
  • image/svg

If needed we can use the preprocessImageFile hook to extend the default image reader and load more image formats (for example HEIC).

Let's set the default imageReader property.

<!DOCTYPE html>

<link rel="stylesheet" href="doka.css" />

<style>
    .my-editor {
        height: 480px;
    }
</style>

<div class="my-editor"></div>

<script type="module">
    import {
        // The method used to register the plugins
        setPlugins,

        // The plugins we want to use
        plugin_crop,
        plugin_finetune,
        plugin_annotate,

        // The method used to render the editor
        appendEditor,

        // Import the default image reader
        createDefaultImageReader,

        // The main UI and plugin locale objects
        locale_en_gb,
        plugin_crop_locale_en_gb,
        plugin_finetune_locale_en_gb,
        plugin_annotate_locale_en_gb,

        // Because we use the annotate plugin we also need
        // to import the markup editor locale
        markup_editor_locale_en_gb,
    } from 'doka.js';

    // This registers the plugins with Doka Image Editor
    setPlugins(plugin_crop, plugin_finetune, plugin_annotate);

    // Merge all the locale objects
    const myLocale = {
        ...locale_en_gb,
        ...plugin_crop_locale_en_gb,
        ...plugin_finetune_locale_en_gb,
        ...plugin_annotate_locale_en_gb,
        ...markup_editor_locale_en_gb,
    };

    // Create the editor
    const doka = appendEditor('.my-editor', {
        // The image to load
        src: './my-image.jpeg',

        // Set default imageReader
        imageReader: createDefaultImageReader(),

        // Set locale
        locale: myLocale,
    });
</script>

Doka Image Editor can now load images and render the user interface.

To show the default tools in the annotate view, and the finetune controls in the Finetune plugin we need to import the default properties.

Setting default plugin properties

The controls for the Finetune util as well as the Annotate util are still missing. That's because we have to set these manually.

We need to import markup_editor_defaults because the Annotate plugin uses the Markup Editor. And we import plugin_finetune_defaults to set the default color adjustment controls in the Finetune plugin.

Below we import both and assign the objects to the appendEditor options argument.

<!DOCTYPE html>

<link rel="stylesheet" href="doka.css" />

<style>
    .my-editor {
        height: 480px;
    }
</style>

<div class="my-editor"></div>

<script type="module">
    import {
        // The method used to register the plugins
        setPlugins,

        // The plugins we want to use
        plugin_crop,
        plugin_finetune,
        plugin_annotate,

        // The method used to render the editor
        appendEditor,

        // Import the default image reader
        createDefaultImageReader,

        // The main UI and plugin locale objects
        locale_en_gb,
        plugin_crop_locale_en_gb,
        plugin_finetune_locale_en_gb,
        plugin_annotate_locale_en_gb,

        // Because we use the annotate plugin we also need
        // to import the markup editor locale
        markup_editor_locale_en_gb,

        // Import the default properties
        markup_editor_defaults,
        plugin_finetune_defaults,
    } from 'doka.js';

    // This registers the plugins with Doka Image Editor
    setPlugins(plugin_crop, plugin_finetune, plugin_annotate);

    // Merge all the locale objects
    const myLocale = {
        ...locale_en_gb,
        ...plugin_crop_locale_en_gb,
        ...plugin_finetune_locale_en_gb,
        ...plugin_annotate_locale_en_gb,
        ...markup_editor_locale_en_gb,
    };

    // Create the editor
    const doka = appendEditor('.my-editor', {
        // The image to load
        src: './my-image.jpeg',

        // Set default imageReader
        imageReader: createDefaultImageReader(),

        // Set Markup Editor defaults
        ...markup_editor_defaults,

        // Set Finetune plugin defaults
        ...plugin_finetune_defaults,

        // Set locale
        locale: myLocale,
    });
</script>

Next steps

With the editor set up, we can continue to configure the editor to our liking with the available instance properties