Alert.php

<?php
/**
 * @link http://www.yiiframework.com/
 * @copyright Copyright (c) 2008 Yii Software LLC
 * @license http://www.yiiframework.com/license/
 */

namespace yii\bootstrap;

use Yii;
use yii\helpers\ArrayHelper;
use yii\helpers\Html;

/**
 * Alert renders an alert bootstrap component.
 *
 * For example,
 *
 * ```php
 * echo Alert::widget([
 *     'options' => [
 *         'class' => 'alert-info',
 *     ],
 *     'body' => 'Say hello...',
 * ]);
 * ```
 *
 * The following example will show the content enclosed between the [[begin()]]
 * and [[end()]] calls within the alert box:
 *
 * ```php
 * Alert::begin([
 *     'options' => [
 *         'class' => 'alert-warning',
 *     ],
 * ]);
 *
 * echo 'Say hello...';
 *
 * Alert::end();
 * ```
 *
 * @see http://getbootstrap.com/components/#alerts
 * @author Antonio Ramirez <amigo.cobos@gmail.com>
 * @since 2.0
 */
class Alert extends Widget
{
    /**
     * @var string the body content in the alert component. Note that anything between
     * the [[begin()]] and [[end()]] calls of the Alert widget will also be treated
     * as the body content, and will be rendered before this.
     */
    public $body;
    /**
     * @var array the options for rendering the close button tag.
     * The close button is displayed in the header of the modal window. Clicking
     * on the button will hide the modal window. If this is false, no close button will be rendered.
     *
     * The following special options are supported:
     *
     * - tag: string, the tag name of the button. Defaults to 'button'.
     * - label: string, the label of the button. Defaults to '&times;'.
     *
     * The rest of the options will be rendered as the HTML attributes of the button tag.
     * Please refer to the [Alert documentation](http://getbootstrap.com/components/#alerts)
     * for the supported HTML attributes.
     */
    public $closeButton = [];


    /**
     * Initializes the widget.
     */
    public function init()
    {
        parent::init();

        $this->initOptions();

        echo Html::beginTag('div', $this->options) . "\n";
        echo $this->renderBodyBegin() . "\n";
    }

    /**
     * Renders the widget.
     */
    public function run()
    {
        echo "\n" . $this->renderBodyEnd();
        echo "\n" . Html::endTag('div');

        $this->registerPlugin('alert');
    }

    /**
     * Renders the close button if any before rendering the content.
     * @return string the rendering result
     */
    protected function renderBodyBegin()
    {
        return $this->renderCloseButton();
    }

    /**
     * Renders the alert body (if any).
     * @return string the rendering result
     */
    protected function renderBodyEnd()
    {
        return $this->body . "\n";
    }

    /**
     * Renders the close button.
     * @return string the rendering result
     */
    protected function renderCloseButton()
    {
        if ($this->closeButton !== false) {
            $tag = ArrayHelper::remove($this->closeButton, 'tag', 'button');
            $label = ArrayHelper::remove($this->closeButton, 'label', '&times;');
            if ($tag === 'button' && !isset($this->closeButton['type'])) {
                $this->closeButton['type'] = 'button';
            }

            return Html::tag($tag, $label, $this->closeButton);
        } else {
            return null;
        }
    }

    /**
     * Initializes the widget options.
     * This method sets the default values for various options.
     */
    protected function initOptions()
    {
        Html::addCssClass($this->options, 'alert');
        Html::addCssClass($this->options, 'fade');
        Html::addCssClass($this->options, 'in');

        if ($this->closeButton !== false) {
            $this->closeButton = array_merge([
                'data-dismiss' => 'alert',
                'aria-hidden' => 'true',
                'class' => 'close',
            ], $this->closeButton);
        }
    }
}