framework/widgets/Breadcrumbs.php
<?php
/**
* @link https://www.yiiframework.com/
* @copyright Copyright (c) 2008 Yii Software LLC
* @license https://www.yiiframework.com/license/
*/
namespace yii\widgets;
use Yii;
use yii\base\InvalidConfigException;
use yii\base\Widget;
use yii\helpers\ArrayHelper;
use yii\helpers\Html;
/**
* Breadcrumbs displays a list of links indicating the position of the current page in the whole site hierarchy.
*
* For example, breadcrumbs like "Home / Sample Post / Edit" means the user is viewing an edit page
* for the "Sample Post". He can click on "Sample Post" to view that page, or he can click on "Home"
* to return to the homepage.
*
* To use Breadcrumbs, you need to configure its [[links]] property, which specifies the links to be displayed. For example,
*
* ```php
* // $this is the view object currently being used
* echo Breadcrumbs::widget([
* 'itemTemplate' => "<li><i>{link}</i></li>\n", // template for all links
* 'links' => [
* [
* 'label' => 'Post Category',
* 'url' => ['post-category/view', 'id' => 10],
* 'template' => "<li><b>{link}</b></li>\n", // template for this link only
* ],
* ['label' => 'Sample Post', 'url' => ['post/edit', 'id' => 1]],
* 'Edit',
* ],
* ]);
* ```
*
* Because breadcrumbs usually appears in nearly every page of a website, you may consider placing it in a layout view.
* You can use a view parameter (e.g. `$this->params['breadcrumbs']`) to configure the links in different
* views. In the layout view, you assign this view parameter to the [[links]] property like the following:
*
* ```php
* // $this is the view object currently being used
* echo Breadcrumbs::widget([
* 'links' => isset($this->params['breadcrumbs']) ? $this->params['breadcrumbs'] : [],
* ]);
* ```
*
* @author Qiang Xue <qiang.xue@gmail.com>
* @since 2.0
*/
class Breadcrumbs extends Widget
{
/**
* @var string the name of the breadcrumb container tag.
*/
public $tag = 'ul';
/**
* @var array the HTML attributes for the breadcrumb container tag.
* @see \yii\helpers\Html::renderTagAttributes() for details on how attributes are being rendered.
*/
public $options = ['class' => 'breadcrumb'];
/**
* @var bool whether to HTML-encode the link labels.
*/
public $encodeLabels = true;
/**
* @var array|null the first hyperlink in the breadcrumbs (called home link).
* Please refer to [[links]] on the format of the link.
* If this property is not set, it will default to a link pointing to [[\yii\web\Application::homeUrl]]
* with the label 'Home'. If this property is false, the home link will not be rendered.
*/
public $homeLink;
/**
* @var array list of links to appear in the breadcrumbs. If this property is empty,
* the widget will not render anything. Each array element represents a single link in the breadcrumbs
* with the following structure:
*
* ```php
* [
* 'label' => 'label of the link', // required
* 'url' => 'url of the link', // optional, will be processed by Url::to()
* 'template' => 'own template of the item', // optional, if not set $this->itemTemplate will be used
* ]
* ```
*
* If a link is active, you only need to specify its "label", and instead of writing `['label' => $label]`,
* you may simply use `$label`.
*
* Since version 2.0.1, any additional array elements for each link will be treated as the HTML attributes
* for the hyperlink tag. For example, the following link specification will generate a hyperlink
* with CSS class `external`:
*
* ```php
* [
* 'label' => 'demo',
* 'url' => 'https://example.com',
* 'class' => 'external',
* ]
* ```
*
* Since version 2.0.3 each individual link can override global [[encodeLabels]] param like the following:
*
* ```php
* [
* 'label' => '<strong>Hello!</strong>',
* 'encode' => false,
* ]
* ```
*/
public $links = [];
/**
* @var string the template used to render each inactive item in the breadcrumbs. The token `{link}`
* will be replaced with the actual HTML link for each inactive item.
*/
public $itemTemplate = "<li>{link}</li>\n";
/**
* @var string the template used to render each active item in the breadcrumbs. The token `{link}`
* will be replaced with the actual HTML link for each active item.
*/
public $activeItemTemplate = "<li class=\"active\">{link}</li>\n";
/**
* Renders the widget.
*/
public function run()
{
if (empty($this->links)) {
return;
}
$links = [];
if ($this->homeLink === null) {
$links[] = $this->renderItem([
'label' => Yii::t('yii', 'Home'),
'url' => Yii::$app->homeUrl,
], $this->itemTemplate);
} elseif ($this->homeLink !== false) {
$links[] = $this->renderItem($this->homeLink, $this->itemTemplate);
}
foreach ($this->links as $link) {
if (!is_array($link)) {
$link = ['label' => $link];
}
$links[] = $this->renderItem($link, isset($link['url']) ? $this->itemTemplate : $this->activeItemTemplate);
}
echo Html::tag($this->tag, implode('', $links), $this->options);
}
/**
* Renders a single breadcrumb item.
* @param array $link the link to be rendered. It must contain the "label" element. The "url" element is optional.
* @param string $template the template to be used to rendered the link. The token "{link}" will be replaced by the link.
* @return string the rendering result
* @throws InvalidConfigException if `$link` does not have "label" element.
*/
protected function renderItem($link, $template)
{
$encodeLabel = ArrayHelper::remove($link, 'encode', $this->encodeLabels);
if (array_key_exists('label', $link)) {
$label = $encodeLabel ? Html::encode($link['label']) : $link['label'];
} else {
throw new InvalidConfigException('The "label" element is required for each link.');
}
if (isset($link['template'])) {
$template = $link['template'];
}
if (isset($link['url'])) {
$options = $link;
unset($options['template'], $options['label'], $options['url']);
$link = Html::a($label, $link['url'], $options);
} else {
$link = $label;
}
return strtr($template, ['{link}' => $link]);
}
}