[WordPress] How to add multiple media uploader buttons on custom option page (an example).

admin.js

$(".image-upload-button").on("click", function (e) {
    var $area = $(this).closest(".image-upload-area"),
        send_to_editor_backup = window.send_to_editor;

    tb_show('', 'media-upload.php?type=image&TB_iframe=true');

    window.send_to_editor = function (html) {
        var imgUrl = $("img", html).attr("src");

        $area.find(".image-url").val(imgUrl);
        $area.find(".image-preview").attr("src", imgUrl);
        tb_remove();

        window.send_to_editor = send_to_editor_backup;
    };
    e.preventDefault();
});

functions.php

<?php
/**
 * Load all necessary assets.
 *
 * @link https://codex.wordpress.org/Plugin_API/Action_Reference/admin_enqueue_scripts
 *
 * @param $hook_suffix
 */
function namespace_options_scripts( $hook_suffix ) {

	wp_register_script( 'admin', get_template_directory_uri() . '/js/admin.js', array(
		'jquery',
		'media-upload',
		'thickbox'
	), '1.0', true );

	if ( 'custom_settings' == $hook_suffix ) {
		wp_enqueue_script( 'jquery' );
		wp_enqueue_script( 'media-upload' );
		wp_enqueue_script( 'thickbox' );
		wp_enqueue_style( 'thickbox' );
		wp_enqueue_script( 'admin' );
	}

}

add_action( 'admin_enqueue_scripts', 'namespace_options_scripts' );

settings.php

<?php
// Get array with images
$images = array(
  '', // 1st image URL
  '', // 2nd image URL
); ?>
<table class="form-table">
	<tbody>
	<tr valign="top">
		<th scope="row">
			<label for="image_url">Image URL</label>
		</th>
		<td class="image-upload-area">
			<input type="url" name="image_url" id="image_url" class="regular-text image-url"
			       value="<?php echo esc_attr( $images[0] ); ?>">
			<button class="button image-upload-button" type="button"><?php _e( 'Select Image' ); ?></button>

			<p>
				<img src="<?php echo esc_url( $images[0] ); ?>" class="image-preview" alt="">
			</p>
		</td>
	</tr>
	<tr valign="top">
		<th scope="row">
			<label for="image_url_2">Image URL 2</label>
		</th>
		<td class="image-upload-area">
			<input type="url" name="image_url_2" id="image_url_2" class="regular-text image-url"
			       value="<?php echo esc_attr( $images[1] ); ?>">
			<button class="button image-upload-button" type="button"><?php _e( 'Select Image' ); ?></button>

			<p>
				<img src="<?php echo esc_url( $images[1] ); ?>" class="image-preview" alt="">
			</p>
		</td>
	</tr>
	</tbody>
</table>