breadcrumb
breadcrumb({ container: string|HTMLElement, attributes: string[], // Optional parameters rootPath: string, separator: string, templates: object, cssClasses: object, transformItems: function, });
1
import { breadcrumb } from 'instantsearch.js/es/widgets';
About this widget
The breadcrumb
widget is a secondary navigation scheme that lets users see where the current page is in relation to the facet’s hierarchy.
It reduces the number of actions a user needs to take to get to a higher-level page and improves the discoverability of the app or website’s sections and pages. It is commonly used for websites with lot of data, organized into categories with subcategories.
Requirements
The objects to use in the breadcrumb must follow this structure:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
[
{
"objectID": "321432",
"name": "lemon",
"categories.lvl0": "products",
"categories.lvl1": "products > fruits"
},
{
"objectID": "8976987",
"name": "orange",
"categories.lvl0": "products",
"categories.lvl1": "products > fruits"
}
]
It’s also possible to provide more than one path for each level:
1
2
3
4
5
6
7
8
[
{
"objectID": "321432",
"name": "lemon",
"categories.lvl0": ["products", "goods"],
"categories.lvl1": ["products > fruits", "goods > to eat"]
}
]
The attributes provided to the widget must be in attributes for faceting, either on the dashboard) or using attributesForFaceting
with the API. By default, the separator is >
(with spaces) but you can use a different one by using the separator option.
If there is also a hierarchicalMenu
on the page, it must follow the same configuration.
Examples
1
2
3
4
5
6
7
8
breadcrumb({
container: '#breadcrumb',
attributes: [
'hierarchicalCategories.lvl0',
'hierarchicalCategories.lvl1',
'hierarchicalCategories.lvl2',
],
});
Options
Parameter | Description | ||
---|---|---|---|
container
|
type: string|HTMLElement
Required
The CSS Selector or |
||
Copy
|
|||
attributes
|
type: string[]
Required
An array of attributes to generate the breadcrumb. |
||
Copy
|
|||
rootPath
|
type: string
Optional
The path to use if the first level is not the root level. Make sure to also include the root path in your UI state—for example, by setting |
||
Copy
|
|||
separator
|
type: string
default: >
Optional
The level separator used in the records. |
||
Copy
|
|||
templates
|
type: object
Optional
The templates to use for the widget. |
||
Copy
|
|||
cssClasses
|
type: object
Optional
The CSS classes you can override:
|
||
Copy
|
|||
transformItems
|
type: function
Optional
Receives the items and is called before displaying them. Should return a new array with the same shape as the original array. Useful for transforming, removing, or reordering items. In addition, the full |
||
Copy
|
Templates
You can customize parts of the widget’s UI using the Templates API.
Every template provides an html
function you can use as a tagged template. Using html
lets you safely provide templates as an HTML string. It works directly in the browser without a build step. See Templating your UI for more information.
The html
function is available starting from v4.46.0.
Parameter | Description | ||
---|---|---|---|
home
|
type: string|function
Optional
The label of the breadcrumb’s first element. |
||
Copy
|
|||
separator
|
type: string|function
Optional
The symbol used to separate the elements of the breadcrumb. |
||
Copy
|
HTML output
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
<div class="ais-Breadcrumb">
<ul class="ais-Breadcrumb-list">
<li class="ais-Breadcrumb-item">
<a class="ais-Breadcrumb-link" href="#">Home</a>
</li>
<li class="ais-Breadcrumb-item">
<span class="ais-Breadcrumb-separator"> > </span>
<a class="ais-Breadcrumb-link" href="#">Cameras & Camcorders</a>
</li>
<li class="ais-Breadcrumb-item ais-Breadcrumb-item--selected">
<span class="ais-Breadcrumb-separator"> > </span>
Digital Cameras
</li>
</ul>
</div>
Customize the UI with connectBreadcrumb
If you want to create your own UI of the breadcrumb
widget, you can use connectors.
To use connectBreadcrumb
, you can import it with the declaration relevant to how you installed InstantSearch.js.
1
import { connectBreadcrumb } from 'instantsearch.js/es/connectors';
Then it’s a 3-step process:
// 1. Create a render function
const renderBreadcrumb = (renderOptions, isFirstRender) => {
// Rendering logic
};
// 2. Create the custom widget
const customBreadcrumb = connectBreadcrumb(
renderBreadcrumb
);
// 3. Instantiate
search.addWidgets([
customBreadcrumb({
// Widget parameters
})
]);
Create a render function
This rendering function is called before the first search (init
lifecycle step)
and each time results come back from Algolia (render
lifecycle step).
const renderBreadcrumb = (renderOptions, isFirstRender) => {
const {
object[] items,
boolean canRefine,
function refine,
function createURL,
object widgetParams,
} = renderOptions;
if (isFirstRender) {
// Do some initial rendering and bind events
}
// Render the widget
};
If SEO is critical to your search page, your custom HTML markup needs to be parsable:
- use plain
<a>
tags withhref
attributes for search engines bots to follow them, - use semantic markup with structured data when relevant, and test it.
Refer to our SEO checklist for building SEO-ready search experiences.
Rendering options
Parameter | Description | ||
---|---|---|---|
items
|
type: object[]
Required
The items to render, containing the keys:
|
||
Copy
|
|||
canRefine
|
type: boolean
Required
Indicates if search state can be refined. |
||
Copy
|
|||
refine
|
type: function
default: (item.value) => undefined
Required
Sets the path of the hierarchical filter and triggers a new search. |
||
Copy
|
|||
createURL
|
type: function
default: (item.value) => string
Required
Generates a URL of the next state of a clicked item. The special value |
||
Copy
|
|||
widgetParams
|
type: object
All original widget options forwarded to the render function. |
||
Copy
|
Create and instantiate the custom widget
We first create custom widgets from our rendering function, then we instantiate them. When doing that, there are two types of parameters you can give:
- Instance parameters: they are predefined parameters that you can use to configure the behavior of Algolia.
- Your own parameters: to make the custom widget generic.
Both instance and custom parameters are available in connector.widgetParams
, inside the renderFunction
.
const customBreadcrumb = connectBreadcrumb(
renderBreadcrumb
);
search.addWidgets([
customBreadcrumb({
attributes: string[],
// Optional instance params
rootPath: string,
separator: string,
transformItems: function,
})
]);
Instance options
Parameter | Description | ||
---|---|---|---|
attributes
|
type: string[]
Required
The attributes to use to generate the hierarchy of the breadcrumb. |
||
Copy
|
|||
rootPath
|
type: string
Optional
The path to use if the first level is not the root level. Make sure to also include the root path in your UI state—for example, by setting |
||
Copy
|
|||
separator
|
type: string
default: >
Optional
The level separator used in the records. |
||
Copy
|
|||
transformItems
|
type: function
Optional
Receives the items and is called before displaying them. Should return a new array with the same shape as the original array. Useful for transforming, removing, or reordering items. In addition, the full |
||
Copy
|
Full example
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
// Create the render function
const renderBreadcrumbItem = ({ item, createURL }) => `
<li>
${
item.value
? `<a
href="${createURL(item.value)}"
data-value="${item.value}"
>
${item.label}
</a>`
: `<span>${item.label}</span>`
}
</li>`;
const renderBreadcrumb = (renderOptions, isFirstRender) => {
const { items, refine, createURL, widgetParams } = renderOptions;
widgetParams.container.innerHTML = `
<ul>
<li>
<a href="#" data-value="">Home</a>
</li>
${items
.map(item =>
renderBreadcrumbItem({
item,
createURL,
})
)
.join('')}
</ul>
`;
[...widgetParams.container.querySelectorAll('a')].forEach(element => {
element.addEventListener('click', event => {
event.preventDefault();
refine(event.currentTarget.dataset.value);
});
});
};
// Create the custom widget
const customBreadcrumb = connectBreadcrumb(
renderBreadcrumb
);
// Instantiate the custom widget
search.addWidgets([
customBreadcrumb({
container: document.querySelector('#breadcrumb'),
attributes: [
'hierarchicalCategories.lvl0',
'hierarchicalCategories.lvl1',
'hierarchicalCategories.lvl2',
],
})
]);