lang-menu.php

<?php

    echo CHtml::link('Выбор языка <span class="fa fa-angle-down"></span>', '#', [
        'id' => 'select-lang-link',
        'data-toggle' => 'dropdown',
    ]);

    $onclick = "
        var p = $(this).parent();
        p.siblings().removeClass('active');
        p.addClass('active');
        $('#select-lang-link').html($(this).html());
        return false;
    ";

    $this->widget('zii.widgets.CMenu', [
        'encodeLabel' => false,
        'items' => [
            ['label' => '<img src="' . $basedir . '/images/russian.jpg"> Русский', 'url' => '#', 'linkOptions' => ['onclick' => $onclick]],
            ['label' => '<img src="' . $basedir . '/images/russian.jpg"> Русский', 'url' => '#', 'linkOptions' => ['onclick' => $onclick]],
            ['label' => '<img src="' . $basedir . '/images/russian.jpg"> Русский', 'url' => '#', 'linkOptions' => ['onclick' => $onclick]],
        ],
        'htmlOptions' => ['class' => 'dropdown-menu', 'role' => 'menu'],
    ]);