Here’s how to do it-
public function widget( $args, $instance ) {
extract( $args );
$widget_id = $args['widget_id'];
$MYVARIABLE = get_field($widget_id.'_ACFFIELDNAME', 'widget');
echo $MYVARIABLE;
...
}
public function form( $instance ) {
$widget_id = $this->id;
...
?>
