pda_handle_upgrade_extension.php

<?php
  /**
	 * Handle auto upgrade extension
	 */
	public function pda_handle_upgrade_extension() {
		$updates = get_plugin_updates();
		$pda_skin = new PDA_WP_Upgrader_Skin();
		include_once ABSPATH . 'wp-admin/includes/class-wp-upgrader.php';
		$upgrader = new Plugin_Upgrader( $pda_skin );
		foreach ( $updates as $plugin ) {
			if ( 'PDA Access Restriction' === $plugin->Name ) {
				if ( version_compare( $plugin->Version, '1.0.4.5' ) < 0 ) {
					$result = $upgrader->upgrade( $plugin->update->plugin );
					if ( $result ) {
						activate_plugin( $plugin->update->plugin, '', false, true );
					}
				}
			}
			if ( 'PDA Membership Integration' === $plugin->Name ) {
				if ( version_compare( $plugin->Version, '1.1.6' ) < 0 ) {
					$result = $upgrader->upgrade( $plugin->update->plugin );
					if ( $result ) {
						activate_plugin( $plugin->update->plugin, '', false, true );
					}
				}
			}
		}
	}
?>