Meta box tamsdoghouse part1

class dropdown_Meta_Box {

	public function __construct() {

		if ( is_admin() ) {
			add_action( 'load-post.php',     array( $this, 'init_metabox' ) );
			add_action( 'load-post-new.php', array( $this, 'init_metabox' ) );
		}

	}

	public function init_metabox() {

		add_action( 'add_meta_boxes',        array( $this, 'add_metabox' )         );
		add_action( 'save_post',             array( $this, 'save_metabox' ), 10, 2 );

	}

	public function add_metabox() {

		add_meta_box(
			'dropdown001',
			__( 'Zijbalk accordion', 'text_domain' ),
			array( $this, 'dropdown_render_metabox' ),
			'page',
			'normal',
			'default'
		);

	}

	public function dropdown_render_metabox( $post ) {

		// Retrieve an existing value from the database.
		$hbaccordion001 = get_post_meta( $post->ID, 'hbaccordion001', true );
		$hbtitelaccordion001 = get_post_meta( $post->ID, 'hbtitelaccordion001', true );
		$hbtekst_accordion001 = get_post_meta( $post->ID, 'hbtekst_accordion001', true );
		$hbtitelaccordion002 = get_post_meta( $post->ID, 'hbtitelaccordion002', true );
		$hbtekst_accordion002 = get_post_meta( $post->ID, 'hbtekst_accordion002', true );
		$hbtitelaccordion003 = get_post_meta( $post->ID, 'hbtitelaccordion003', true );
		$hbtekst_accordion003 = get_post_meta( $post->ID, 'hbtekst_accordion003', true );

		// Set default values.
		if( empty( $hbaccordion001 ) ) $hbaccordion001 = 'True';
		if( empty( $hbtitelaccordion001 ) ) $hbtitelaccordion001 = '';
		if( empty( $hbtekst_accordion001 ) ) $hbtekst_accordion001 = '';
		if( empty( $hbtitelaccordion002 ) ) $hbtitelaccordion002 = '';
		if( empty( $hbtekst_accordion002 ) ) $hbtekst_accordion002 = '';
		if( empty( $hbtitelaccordion003 ) ) $hbtitelaccordion003 = '';
		if( empty( $hbtekst_accordion003 ) ) $hbtekst_accordion003 = '';

		// Form fields.
		echo '<table class="form-table">';

		echo '	<tr>';
		echo '		<th><label for="hbaccordion001" class="hbaccordion001_label">' . __( 'Zijbalk accordion actief ?', 'text_domain' ) . '</label></th>';
		echo '		<td>';
		echo '			<label><input type="checkbox" id="hbaccordion001" name="hbaccordion001" class="hbaccordion001_field" value="checked" ' . checked( $hbaccordion001, 'checked', false ) . '> ' . __( '', 'text_domain' ) . '</label>';
		echo '		</td>';
		echo '	</tr>';

		echo '	<tr>';
		echo '		<th><label for="hbtitelaccordion001" class="hbtitelaccordion001_label">' . __( 'Titel Accordion 1', 'text_domain' ) . '</label></th>';
		echo '		<td>';
		echo '			<input type="text" id="hbtitelaccordion001" name="hbtitelaccordion001" class="hbtitelaccordion001_field" placeholder="' . esc_attr__( '', 'text_domain' ) . '" value="' . esc_attr( $hbtitelaccordion001 ) . '">';
		echo '		</td>';
		echo '	</tr>';

		echo '	<tr>';
		echo '		<th><label for="hbtekst_accordion001" class="hbtekst_accordion001_label">' . __( 'Tekst accordion', 'text_domain' ) . '</label></th>';
		echo '		<td>';
		wp_editor( $hbtekst_accordion001, 'hbtekst_accordion001', array( 'media_buttons' => true ) );
		echo '		</td>';
		echo '	</tr>';

		echo '	<tr>';
		echo '		<th><label for="hbtitelaccordion002" class="hbtitelaccordion002_label">' . __( 'Titel Accordion 2', 'text_domain' ) . '</label></th>';
		echo '		<td>';
		echo '			<input type="text" id="hbtitelaccordion002" name="hbtitelaccordion002" class="hbtitelaccordion002_field" placeholder="' . esc_attr__( '', 'text_domain' ) . '" value="' . esc_attr( $hbtitelaccordion002 ) . '">';
		echo '		</td>';
		echo '	</tr>';

		echo '	<tr>';
		echo '		<th><label for="hbtekst_accordion002" class="hbtekst_accordion002_label">' . __( 'Tekst accordion', 'text_domain' ) . '</label></th>';
		echo '		<td>';
		wp_editor( $hbtekst_accordion002, 'hbtekst_accordion002', array( 'media_buttons' => true ) );
		echo '		</td>';
		echo '	</tr>';

		echo '	<tr>';
		echo '		<th><label for="hbtitelaccordion003" class="hbtitelaccordion003_label">' . __( 'Titel Accordion 3', 'text_domain' ) . '</label></th>';
		echo '		<td>';
		echo '			<input type="text" id="hbtitelaccordion003" name="hbtitelaccordion003" class="hbtitelaccordion003_field" placeholder="' . esc_attr__( '', 'text_domain' ) . '" value="' . esc_attr( $hbtitelaccordion003 ) . '">';
		echo '		</td>';
		echo '	</tr>';

		echo '	<tr>';
		echo '		<th><label for="hbtekst_accordion003" class="hbtekst_accordion003_label">' . __( 'Tekst accordion', 'text_domain' ) . '</label></th>';
		echo '		<td>';
		wp_editor( $hbtekst_accordion003, 'hbtekst_accordion003', array( 'media_buttons' => true ) );
		echo '		</td>';
		echo '	</tr>';

		echo '</table>';

	}

	public function save_metabox( $post_id, $post ) {

		// Sanitize user input.
		$hbnew_accordion001 = isset( $_POST[ 'hbaccordion001' ] ) ? 'checked'  : '';
		$hbnew_titelaccordion001 = isset( $_POST[ 'hbtitelaccordion001' ] ) ? sanitize_text_field( $_POST[ 'hbtitelaccordion001' ] ) : '';
		$hbnew_tekst_accordion001 = isset( $_POST[ 'hbtekst_accordion001' ] ) ? wp_kses_post( $_POST[ 'hbtekst_accordion001' ] ) : '';
		$hbnew_titelaccordion002 = isset( $_POST[ 'hbtitelaccordion002' ] ) ? sanitize_text_field( $_POST[ 'hbtitelaccordion002' ] ) : '';
		$hbnew_tekst_accordion002 = isset( $_POST[ 'hbtekst_accordion002' ] ) ? wp_kses_post( $_POST[ 'hbtekst_accordion002' ] ) : '';
		$hbnew_titelaccordion003 = isset( $_POST[ 'hbtitelaccordion003' ] ) ? sanitize_text_field( $_POST[ 'hbtitelaccordion003' ] ) : '';
		$hbnew_tekst_accordion003 = isset( $_POST[ 'hbtekst_accordion003' ] ) ? wp_kses_post( $_POST[ 'hbtekst_accordion003' ] ) : '';

		// Update the meta field in the database.
		update_post_meta( $post_id, 'hbaccordion001', $hbnew_accordion001 );
		update_post_meta( $post_id, 'hbtitelaccordion001', $hbnew_titelaccordion001 );
		update_post_meta( $post_id, 'hbtekst_accordion001', $hbnew_tekst_accordion001 );
		update_post_meta( $post_id, 'hbtitelaccordion002', $hbnew_titelaccordion002 );
		update_post_meta( $post_id, 'hbtekst_accordion002', $hbnew_tekst_accordion002 );
		update_post_meta( $post_id, 'hbtitelaccordion003', $hbnew_titelaccordion003 );
		update_post_meta( $post_id, 'hbtekst_accordion003', $hbnew_tekst_accordion003 );

	}

}

new dropdown_Meta_Box;