Class yii\bootstrap4\Dropdown

All Classes | Properties | Methods

Inheritance	yii\bootstrap4\Dropdown » yii\bootstrap4\Widget » yii\base\Widget
Uses Traits	yii\bootstrap4\BootstrapWidgetTrait
Source Code	https://github.com/yiisoft/yii2-bootstrap4/blob/master/src/Dropdown.php

Dropdown renders a Bootstrap dropdown menu component.

For example,

<div class="dropdown">
    <a href="#" data-toggle="dropdown" class="dropdown-toggle">Label <b class="caret"></b></a>
    <?php
        echo Dropdown::widget([
            'items' => [
                ['label' => 'DropdownA', 'url' => '/'],
                ['label' => 'DropdownB', 'url' => '#'],
            ],
        ]);
    ?>
</div>

Public Properties

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Property	Type	Description	Defined By
$clientEvents	array	The event handlers for the underlying Bootstrap JS plugin.	yii\bootstrap4\BootstrapWidgetTrait
$clientOptions	array	The options for the underlying Bootstrap JS plugin.	yii\bootstrap4\BootstrapWidgetTrait
$encodeLabels	boolean	Whether the labels for header items should be HTML-encoded.	yii\bootstrap4\Dropdown
$items	array	List of menu items in the dropdown.	yii\bootstrap4\Dropdown
$options	array	The HTML attributes for the widget container tag.	yii\bootstrap4\Widget
$submenuOptions	array\|null	The HTML attributes for sub-menu container tags.	yii\bootstrap4\Dropdown

Public Methods

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Method	Description	Defined By
getView()		yii\bootstrap4\BootstrapWidgetTrait
init()	Initializes the widget.	yii\bootstrap4\Dropdown
run()	Renders the widget.	yii\bootstrap4\Dropdown

Protected Methods

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Method	Description	Defined By
registerClientEvents()	Registers JS event handlers that are listed in $clientEvents.	yii\bootstrap4\BootstrapWidgetTrait
registerPlugin()	Registers a specific Bootstrap plugin and the related events	yii\bootstrap4\BootstrapWidgetTrait
renderItems()	Renders menu items.	yii\bootstrap4\Dropdown

Property Details

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$encodeLabels public property

Whether the labels for header items should be HTML-encoded.

public boolean $encodeLabels = true

$items public property

List of menu items in the dropdown. Each array element can be either an HTML string, or an array representing a single menu with the following structure:

label: string, required, the label of the item link.
encode: bool, optional, whether to HTML-encode item label.
url: string|array, optional, the URL of the item link. This will be processed by \yii\helpers\Url::to(). If not set, the item will be treated as a menu header when the item has no sub-menu.
visible: bool, optional, whether this menu item is visible. Defaults to true.
disabled: bool, optional, whether this menu item is disabled. Defaults to false.
linkOptions: array, optional, the HTML attributes of the item link.
options: array, optional, the HTML attributes of the item.
active: bool, optional, whether the item should be on active state or not.
items: array, optional, the submenu items. The structure is the same as this property. Note that Bootstrap doesn't support dropdown submenu. You have to add your own CSS styles to support it.
submenuOptions: array, optional, the HTML attributes for sub-menu container tag. If specified it will be merged with $submenuOptions.

To insert divider use -.

public array $items = []

$submenuOptions public property

The HTML attributes for sub-menu container tags.

public array|null $submenuOptions = []

Method Details

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getView() public abstract method

Defined in: yii\bootstrap4\BootstrapWidgetTrait::getView()

See also \yii\base\Widget::getView().

public abstract \yii\web\View getView ( )
return	\yii\web\View	The view object that can be used to render views or view files.

Source code

                abstract function getView();

init() public method

Initializes the widget.

This method will register the bootstrap asset bundle. If you override this method, make sure you call the parent implementation first.

public void init ( )

Source code

                public function init()
{
    parent::init();
    Html::addCssClass($this->options, ['widget' => 'dropdown-menu']);
}

registerClientEvents() protected method

Defined in: yii\bootstrap4\BootstrapWidgetTrait::registerClientEvents()

Registers JS event handlers that are listed in $clientEvents.

protected void registerClientEvents ( )

Source code

                protected function registerClientEvents()
{
    if (!empty($this->clientEvents)) {
        $id = $this->options['id'];
        $js = [];
        foreach ($this->clientEvents as $event => $handler) {
            $js[] = "jQuery('#$id').on('$event', $handler);";
        }
        $this->getView()->registerJs(implode("\n", $js));
    }
}

registerPlugin() protected method

Defined in: yii\bootstrap4\BootstrapWidgetTrait::registerPlugin()

Registers a specific Bootstrap plugin and the related events

protected void registerPlugin ( $name )
$name	string	The name of the Bootstrap plugin

Source code

                protected function registerPlugin($name)
{
    $view = $this->getView();
    BootstrapPluginAsset::register($view);
    $id = $this->options['id'];
    if ($this->clientOptions !== false) {
        $options = empty($this->clientOptions) ? '' : Json::htmlEncode($this->clientOptions);
        $js = "jQuery('#$id').$name($options);";
        $view->registerJs($js);
    }
    $this->registerClientEvents();
}

renderItems() protected method

Renders menu items.

protected string renderItems ( $items, $options = [] )
$items	array	The menu items to be rendered
$options	array	The container HTML attributes
return	string	The rendering result.
throws	\yii\base\InvalidConfigException	if the label option is not specified in one of the items.
throws	Exception

Source code

                protected function renderItems($items, $options = [])
{
    $lines = [];
    foreach ($items as $item) {
        if (is_string($item)) {
            $lines[] = ($item === '-')
                ? Html::tag('div', '', ['class' => 'dropdown-divider'])
                : $item;
            continue;
        }
        if (isset($item['visible']) && !$item['visible']) {
            continue;
        }
        if (!array_key_exists('label', $item)) {
            throw new InvalidConfigException("The 'label' option is required.");
        }
        $encodeLabel = isset($item['encode']) ? $item['encode'] : $this->encodeLabels;
        $label = $encodeLabel ? Html::encode($item['label']) : $item['label'];
        $itemOptions = ArrayHelper::getValue($item, 'options', []);
        $linkOptions = ArrayHelper::getValue($item, 'linkOptions', []);
        $active = ArrayHelper::getValue($item, 'active', false);
        $disabled = ArrayHelper::getValue($item, 'disabled', false);
        Html::addCssClass($linkOptions, ['widget' => 'dropdown-item']);
        if ($disabled) {
            ArrayHelper::setValue($linkOptions, 'tabindex', '-1');
            ArrayHelper::setValue($linkOptions, 'aria-disabled', 'true');
            Html::addCssClass($linkOptions, ['disable' => 'disabled']);
        } elseif ($active) {
            Html::addCssClass($linkOptions, ['activate' => 'active']);
        }
        $url = array_key_exists('url', $item) ? $item['url'] : null;
        if (empty($item['items'])) {
            if ($url === null) {
                $content = Html::tag('h6', $label, ['class' => 'dropdown-header']);
            } else {
                $content = Html::a($label, $url, $linkOptions);
            }
            $lines[] = $content;
        } else {
            $submenuOptions = $this->submenuOptions;
            if (isset($item['submenuOptions'])) {
                $submenuOptions = array_merge($submenuOptions, $item['submenuOptions']);
            }
            Html::addCssClass($submenuOptions, ['widget' => 'dropdown-submenu dropdown-menu']);
            Html::addCssClass($linkOptions, ['toggle' => 'dropdown-toggle']);
            $lines[] = Html::beginTag('div', array_merge_recursive(['class' => ['dropdown'], 'aria-expanded' => 'false'], $itemOptions));
            $lines[] = Html::a($label, $url, array_merge([
                'data-toggle' => 'dropdown',
                'aria-haspopup' => 'true',
                'aria-expanded' => 'false',
                'role' => 'button'
            ], $linkOptions));
            $lines[] = static::widget([
                'items' => $item['items'],
                'options' => $submenuOptions,
                'submenuOptions' => $submenuOptions,
                'encodeLabels' => $this->encodeLabels
            ]);
            $lines[] = Html::endTag('div');
        }
    }
    return Html::tag('div', implode("\n", $lines), $options);
}

run() public method

Renders the widget.

public void run ( )
throws	\yii\base\InvalidConfigException

Source code

                public function run()
{
    BootstrapPluginAsset::register($this->getView());
    $this->registerClientEvents();
    return $this->renderItems($this->items, $this->options);
}