WordPress at a glance
class is not described

WP_Widget_Media_Image{} WP 4.8.0

Core class that implements an image widget.

No Hooks.

Return

Nothing (null).

Usage

$WP_Widget_Media_Image = new WP_Widget_Media_Image();
// use class methods

Methods

  1. __construct()
  2. get_instance_schema()
  3. render_media( $instance )
  4. enqueue_admin_scripts()
  5. render_control_template_scripts()

Code of WP Widget Media Image: wp-includes/widgets/class-wp-widget-media-image.php WP 5.2.2

<?php
class WP_Widget_Media_Image extends WP_Widget_Media {

	/**
	 * Constructor.
	 *
	 * @since 4.8.0
	 */
	public function __construct() {
		parent::__construct(
			'media_image',
			__( 'Image' ),
			array(
				'description' => __( 'Displays an image.' ),
				'mime_type'   => 'image',
			)
		);

		$this->l10n = array_merge(
			$this->l10n,
			array(
				'no_media_selected'          => __( 'No image selected' ),
				'add_media'                  => _x( 'Add Image', 'label for button in the image widget' ),
				'replace_media'              => _x( 'Replace Image', 'label for button in the image widget; should preferably not be longer than ~13 characters long' ),
				'edit_media'                 => _x( 'Edit Image', 'label for button in the image widget; should preferably not be longer than ~13 characters long' ),
				'missing_attachment'         => sprintf(
					/* translators: %s: URL to media library */
					__( 'We can&#8217;t find that image. Check your <a href="%s">media library</a> and make sure it wasn&#8217;t deleted.' ),
					esc_url( admin_url( 'upload.php' ) )
				),
				/* translators: %d: widget count */
				'media_library_state_multi'  => _n_noop( 'Image Widget (%d)', 'Image Widget (%d)' ),
				'media_library_state_single' => __( 'Image Widget' ),
			)
		);
	}

	/**
	 * Get schema for properties of a widget instance (item).
	 *
	 * @since 4.8.0
	 *
	 * @see WP_REST_Controller::get_item_schema()
	 * @see WP_REST_Controller::get_additional_fields()
	 * @link https://core.trac.wordpress.org/ticket/35574
	 * @return array Schema for properties.
	 */
	public function get_instance_schema() {
		return array_merge(
			array(
				'size'              => array(
					'type'        => 'string',
					'enum'        => array_merge( get_intermediate_image_sizes(), array( 'full', 'custom' ) ),
					'default'     => 'medium',
					'description' => __( 'Size' ),
				),
				'width'             => array( // Via 'customWidth', only when size=custom; otherwise via 'width'.
					'type'        => 'integer',
					'minimum'     => 0,
					'default'     => 0,
					'description' => __( 'Width' ),
				),
				'height'            => array( // Via 'customHeight', only when size=custom; otherwise via 'height'.
					'type'        => 'integer',
					'minimum'     => 0,
					'default'     => 0,
					'description' => __( 'Height' ),
				),

				'caption'           => array(
					'type'                  => 'string',
					'default'               => '',
					'sanitize_callback'     => 'wp_kses_post',
					'description'           => __( 'Caption' ),
					'should_preview_update' => false,
				),
				'alt'               => array(
					'type'              => 'string',
					'default'           => '',
					'sanitize_callback' => 'sanitize_text_field',
					'description'       => __( 'Alternative Text' ),
				),
				'link_type'         => array(
					'type'                  => 'string',
					'enum'                  => array( 'none', 'file', 'post', 'custom' ),
					'default'               => 'custom',
					'media_prop'            => 'link',
					'description'           => __( 'Link To' ),
					'should_preview_update' => true,
				),
				'link_url'          => array(
					'type'                  => 'string',
					'default'               => '',
					'format'                => 'uri',
					'media_prop'            => 'linkUrl',
					'description'           => __( 'URL' ),
					'should_preview_update' => true,
				),
				'image_classes'     => array(
					'type'                  => 'string',
					'default'               => '',
					'sanitize_callback'     => array( $this, 'sanitize_token_list' ),
					'media_prop'            => 'extraClasses',
					'description'           => __( 'Image CSS Class' ),
					'should_preview_update' => false,
				),
				'link_classes'      => array(
					'type'                  => 'string',
					'default'               => '',
					'sanitize_callback'     => array( $this, 'sanitize_token_list' ),
					'media_prop'            => 'linkClassName',
					'should_preview_update' => false,
					'description'           => __( 'Link CSS Class' ),
				),
				'link_rel'          => array(
					'type'                  => 'string',
					'default'               => '',
					'sanitize_callback'     => array( $this, 'sanitize_token_list' ),
					'media_prop'            => 'linkRel',
					'description'           => __( 'Link Rel' ),
					'should_preview_update' => false,
				),
				'link_target_blank' => array(
					'type'                  => 'boolean',
					'default'               => false,
					'media_prop'            => 'linkTargetBlank',
					'description'           => __( 'Open link in a new tab' ),
					'should_preview_update' => false,
				),
				'image_title'       => array(
					'type'                  => 'string',
					'default'               => '',
					'sanitize_callback'     => 'sanitize_text_field',
					'media_prop'            => 'title',
					'description'           => __( 'Image Title Attribute' ),
					'should_preview_update' => false,
				),

				/*
				 * There are two additional properties exposed by the PostImage modal
				 * that don't seem to be relevant, as they may only be derived read-only
				 * values:
				 * - originalUrl
				 * - aspectRatio
				 * - height (redundant when size is not custom)
				 * - width (redundant when size is not custom)
				 */
			),
			parent::get_instance_schema()
		);
	}

	/**
	 * Render the media on the frontend.
	 *
	 * @since 4.8.0
	 *
	 * @param array $instance Widget instance props.
	 * @return void
	 */
	public function render_media( $instance ) {
		$instance = array_merge( wp_list_pluck( $this->get_instance_schema(), 'default' ), $instance );
		$instance = wp_parse_args(
			$instance,
			array(
				'size' => 'thumbnail',
			)
		);

		$attachment = null;
		if ( $this->is_attachment_with_mime_type( $instance['attachment_id'], $this->widget_options['mime_type'] ) ) {
			$attachment = get_post( $instance['attachment_id'] );
		}
		if ( $attachment ) {
			$caption = '';
			if ( ! isset( $instance['caption'] ) ) {
				$caption = $attachment->post_excerpt;
			} elseif ( trim( $instance['caption'] ) ) {
				$caption = $instance['caption'];
			}

			$image_attributes = array(
				'class' => sprintf( 'image wp-image-%d %s', $attachment->ID, $instance['image_classes'] ),
				'style' => 'max-width: 100%; height: auto;',
			);
			if ( ! empty( $instance['image_title'] ) ) {
				$image_attributes['title'] = $instance['image_title'];
			}

			if ( $instance['alt'] ) {
				$image_attributes['alt'] = $instance['alt'];
			}

			$size = $instance['size'];
			if ( 'custom' === $size || ! in_array( $size, array_merge( get_intermediate_image_sizes(), array( 'full' ) ), true ) ) {
				$size = array( $instance['width'], $instance['height'] );
			}
			$image_attributes['class'] .= sprintf( ' attachment-%1$s size-%1$s', is_array( $size ) ? join( 'x', $size ) : $size );

			$image = wp_get_attachment_image( $attachment->ID, $size, false, $image_attributes );

			$caption_size = _wp_get_image_size_from_meta( $instance['size'], wp_get_attachment_metadata( $attachment->ID ) );
			$width        = empty( $caption_size[0] ) ? 0 : $caption_size[0];

		} else {
			if ( empty( $instance['url'] ) ) {
				return;
			}

			$instance['size'] = 'custom';
			$caption          = $instance['caption'];
			$width            = $instance['width'];
			$classes          = 'image ' . $instance['image_classes'];
			if ( 0 === $instance['width'] ) {
				$instance['width'] = '';
			}
			if ( 0 === $instance['height'] ) {
				$instance['height'] = '';
			}

			$image = sprintf(
				'<img class="%1$s" src="%2$s" alt="%3$s" width="%4$s" height="%5$s" />',
				esc_attr( $classes ),
				esc_url( $instance['url'] ),
				esc_attr( $instance['alt'] ),
				esc_attr( $instance['width'] ),
				esc_attr( $instance['height'] )
			);
		} // End if().

		$url = '';
		if ( 'file' === $instance['link_type'] ) {
			$url = $attachment ? wp_get_attachment_url( $attachment->ID ) : $instance['url'];
		} elseif ( $attachment && 'post' === $instance['link_type'] ) {
			$url = get_attachment_link( $attachment->ID );
		} elseif ( 'custom' === $instance['link_type'] && ! empty( $instance['link_url'] ) ) {
			$url = $instance['link_url'];
		}

		if ( $url ) {
			$link = sprintf( '<a href="%s"', esc_url( $url ) );
			if ( ! empty( $instance['link_classes'] ) ) {
				$link .= sprintf( ' class="%s"', esc_attr( $instance['link_classes'] ) );
			}
			if ( ! empty( $instance['link_rel'] ) ) {
				$link .= sprintf( ' rel="%s"', esc_attr( $instance['link_rel'] ) );
			}
			if ( ! empty( $instance['link_target_blank'] ) ) {
				$link .= ' target="_blank"';
			}
			$link .= '>';
			$link .= $image;
			$link .= '</a>';
			$image = wp_targeted_link_rel( $link );
		}

		if ( $caption ) {
			$image = img_caption_shortcode(
				array(
					'width'   => $width,
					'caption' => $caption,
				),
				$image
			);
		}

		echo $image;
	}

	/**
	 * Loads the required media files for the media manager and scripts for media widgets.
	 *
	 * @since 4.8.0
	 */
	public function enqueue_admin_scripts() {
		parent::enqueue_admin_scripts();

		$handle = 'media-image-widget';
		wp_enqueue_script( $handle );

		$exported_schema = array();
		foreach ( $this->get_instance_schema() as $field => $field_schema ) {
			$exported_schema[ $field ] = wp_array_slice_assoc( $field_schema, array( 'type', 'default', 'enum', 'minimum', 'format', 'media_prop', 'should_preview_update' ) );
		}
		wp_add_inline_script(
			$handle,
			sprintf(
				'wp.mediaWidgets.modelConstructors[ %s ].prototype.schema = %s;',
				wp_json_encode( $this->id_base ),
				wp_json_encode( $exported_schema )
			)
		);

		wp_add_inline_script(
			$handle,
			sprintf(
				'
					wp.mediaWidgets.controlConstructors[ %1$s ].prototype.mime_type = %2$s;
					wp.mediaWidgets.controlConstructors[ %1$s ].prototype.l10n = _.extend( {}, wp.mediaWidgets.controlConstructors[ %1$s ].prototype.l10n, %3$s );
				',
				wp_json_encode( $this->id_base ),
				wp_json_encode( $this->widget_options['mime_type'] ),
				wp_json_encode( $this->l10n )
			)
		);
	}

	/**
	 * Render form template scripts.
	 *
	 * @since 4.8.0
	 */
	public function render_control_template_scripts() {
		parent::render_control_template_scripts();

		?>
		<script type="text/html" id="tmpl-wp-media-widget-image-fields">
			<# var elementIdPrefix = 'el' + String( Math.random() ) + '_'; #>
			<# if ( data.url ) { #>
			<p class="media-widget-image-link">
				<label for="{{ elementIdPrefix }}linkUrl"><?php esc_html_e( 'Link to:' ); ?></label>
				<input id="{{ elementIdPrefix }}linkUrl" type="text" class="widefat link" value="{{ data.link_url }}" placeholder="http://" pattern="((\w+:)?\/\/\w.*|\w+:(?!\/\/$)|\/|\?|#).*">
			</p>
			<# } #>
		</script>
		<script type="text/html" id="tmpl-wp-media-widget-image-preview">
			<# if ( data.error && 'missing_attachment' === data.error ) { #>
				<div class="notice notice-error notice-alt notice-missing-attachment">
					<p><?php echo $this->l10n['missing_attachment']; ?></p>
				</div>
			<# } else if ( data.error ) { #>
				<div class="notice notice-error notice-alt">
					<p><?php _e( 'Unable to preview media due to an unknown error.' ); ?></p>
				</div>
			<# } else if ( data.url ) { #>
				<img class="attachment-thumb" src="{{ data.url }}" draggable="false" alt="{{ data.alt }}"
					<# if ( ! data.alt && data.currentFilename ) { #>
						aria-label="
						<?php
						echo esc_attr(
							sprintf(
								/* translators: %s: the image file name. */
								__( 'The current image has no alternative text. The file name is: %s' ),
								'{{ data.currentFilename }}'
							)
						);
						?>
						"
					<# } #>
				/>
			<# } #>
		</script>
		<?php
	}
}