media-uploader.php

add_action( 'admin_enqueue_scripts', 'example_register_script', 10 );
function example_register_script() {
	wp_enqueue_media();  /* WordPressのメディアアップローダーを利用可能にします。 */
	wp_enqueue_script(
		'example-uploader',
		/path/to/example-uploader.js',
		array( 'jquery' ),
		'1.0.0',
		false
	);
}

wp-media-uploader-html.php

<div class="example-uploader">
	<h2>画像</h2>
	<form method="post" action="">
		<div class="image-block">
			<div class="image-elem">
				<input type="text" class="image-url" name="image-url" size="50">
			</div>
			<div class="image-elem">
				<button class="image-select">画像追加</button>
			</div>
			<div class="image-elem">
				<div class="image-preview"></div>
			</div>
			<div class="image-elem">
				<button class="image-remove">画像削除</button>
			</div>
		</div>
	</form>
</div>

wp-media-uploader.js

jQuery( function ( $ ) {

	$( ".image-select" ).on( "click", function () {
		var media_loader, parent;

		parent = $( this ).parents( ".image-block" );

		if ( media_loader ) {
			media_loader.open();
			return;
		}

		/** @var object wp recieved form wordpress */
		media_loader = wp.media( {
			title: "Insert",
			button: {
				text: "Insert"
			},
			multiple: false
		} );

		media_loader.on( "select", function () {
			var image, preview;
			image = media_loader.state().get( "selection" );
			preview = $( ".image-preview", parent );
			image.each( function ( file ) {
				$( ".image-url", parent ).val( file.toJSON().url );
				var img = $( "img", preview );
				if ( img.length === 0 ) {
					preview.append( '<img src="' + file.toJSON().url + '">' );
				} else {
					img.attr( "src", file.toJSON().url );
				}
				preview.css( "display", "block" );
			} );
		} );
		media_loader.open();
		return false;

	} );

	// Remove images
	$( ".image-remove" ).on( 'click', function ( e ) {
		var parent, preview;
		parent = $( this ).parents( ".image-block" );
		$( ".image-url", parent ).val( "" );
		preview = $( ".image-preview", parent );
		if ( $( "img", preview ).length > 0 ) {
			$( "img", preview ).remove();
		}
		return false;
	} );

});