Hide Dashboard Admin Bar For Non Admins.

yzc_hide_dashboard_for_non_admins.php

<?php

/**
 * Hide Dashboard Admin Bar For Non Admins.
 */
function yzc_hide_dashboard_for_non_admins() {

    if ( current_user_can( 'administrator' ) ) {
        return false;
    }

    // Hide Admin Bar.
    if ( ! is_admin() ) {
        show_admin_bar( false );
    }

    // Hide Admin Dashboard.
    if ( is_admin() &&
        ! ( defined( 'DOING_AJAX' ) && DOING_AJAX ) ) {
        wp_redirect( home_url() );
        exit;
    }

}

add_action( 'init', 'yzc_hide_dashboard_for_non_admins', 99 );