Split show_form into render_form_open, render_form_close, and render_…

…field, and return field objects whenever possible. Closes #506

includes/CMB2.php

@@ -152,6 +152,24 @@ public function __construct( $meta_box, $object_id = 0 ) {
 	 * @param string $object_type Type of object being saved. (e.g., post, user, or comment)
 	 */
 	public function show_form( $object_id = 0, $object_type = '' ) {
+		$this->render_form_open( $object_id, $object_type );
+
+		foreach ( $this->prop( 'fields' ) as $field_args ) {
+			$this->render_field( $field_args );
+		}
+
+		$this->render_form_close( $object_id, $object_type );
+	}
+
+	/**
+	 * Outputs the opening form markup and runs corresponding hooks:
+	 * 'cmb2_before_form' and "cmb2_before_{$object_type}_form_{$this->cmb_id}"
+	 * @since  2.1.3
+	 * @param  integer $object_id   Object ID
+	 * @param  string  $object_type Object type
+	 * @return void
+	 */
+	public function render_form_open( $object_id = 0, $object_type = '' ) {
 		$object_type = $this->object_type( $object_type );
 		$object_id = $this->object_id( $object_id );
 
@@ -188,33 +206,19 @@ public function show_form( $object_id = 0, $object_type = '' ) {
 
 		echo '<div class="cmb2-wrap form-table"><div id="cmb2-metabox-', sanitize_html_class( $this->cmb_id ), '" class="cmb2-metabox cmb-field-list">';
 
-		foreach ( $this->prop( 'fields' ) as $field_args ) {
-
-			$field_args['context'] = $this->prop( 'context' );
-
-			if ( 'group' == $field_args['type'] ) {
-
-				if ( ! isset( $field_args['show_names'] ) ) {
-					$field_args['show_names'] = $this->prop( 'show_names' );
-				}
-				$this->render_group( $field_args );
-
-			} elseif ( 'hidden' == $field_args['type'] && $this->get_field( $field_args )->should_show() ) {
-				// Save rendering for after the metabox
-				$this->add_hidden_field( array(
-					'field_args'  => $field_args,
-					'object_type' => $this->object_type(),
-					'object_id'   => $this->object_id(),
-				) );
-
-			} else {
-
-				$field_args['show_names'] = $this->prop( 'show_names' );
+	}
 
-				// Render default fields
-				$field = $this->get_field( $field_args )->render_field();
-			}
-		}
+	/**
+	 * Outputs the closing form markup and runs corresponding hooks:
+	 * 'cmb2_after_form' and "cmb2_after_{$object_type}_form_{$this->cmb_id}"
+	 * @since  2.1.3
+	 * @param  integer $object_id   Object ID
+	 * @param  string  $object_type Object type
+	 * @return void
+	 */
+	public function render_form_close( $object_id = 0, $object_type = '' ) {
+		$object_type = $this->object_type( $object_type );
+		$object_id = $this->object_id( $object_id );
 
 		echo '</div></div>';
 
@@ -251,8 +255,44 @@ public function show_form( $object_id = 0, $object_type = '' ) {
 	}
 
 	/**
-	 * Render a repeatable group
-	 * @param array $args Array of field arguments for a group field parent
+	 * Renders a field based on the field type
+	 * @since  2.1.3
+	 * @param  array $field_args A field configuration array.
+	 * @return mixed CMB2_Field object if successful.
+	 */
+	public function render_field( $field_args ) {
+		$field_args['context'] = $this->prop( 'context' );
+
+		if ( 'group' == $field_args['type'] ) {
+
+			if ( ! isset( $field_args['show_names'] ) ) {
+				$field_args['show_names'] = $this->prop( 'show_names' );
+			}
+			$field = $this->render_group( $field_args );
+
+		} elseif ( 'hidden' == $field_args['type'] && $this->get_field( $field_args )->should_show() ) {
+			// Save rendering for after the metabox
+			$field = $this->add_hidden_field( array(
+				'field_args'  => $field_args,
+				'object_type' => $this->object_type(),
+				'object_id'   => $this->object_id(),
+			) );
+
+		} else {
+
+			$field_args['show_names'] = $this->prop( 'show_names' );
+
+			// Render default fields
+			$field = $this->get_field( $field_args )->render_field();
+		}
+
+		return $field;
+	}
+
+	/**
+	 * Render a repeatable group.
+	 * @param array $args Array of field arguments for a group field parent.
+	 * @return CMB2_Field|null Group field object.
 	 */
 	public function render_group( $args ) {
 
@@ -310,6 +350,7 @@ public function render_group( $args ) {
 
 		$field_group->peform_param_callback( 'after_group' );
 
+		return $field_group;
 	}
 
 	/**
@@ -376,7 +417,10 @@ public function render_group_row( $field_group, $remove_disabled ) {
 	 * @param array  $args Array of arguments to be passed to CMB2_Field
 	 */
 	public function add_hidden_field( $args ) {
-		$this->hidden_fields[] = new CMB2_Types( new CMB2_Field( $args ) );
+		$field = new CMB2_Field( $args );
+		$this->hidden_fields[] = new CMB2_Types( $field );
+
+		return $field;
 	}
 
 	/**