src/Theme/Theme.php
public function set($theme)
    {
        if (!$this->has($theme)) {
            throw new ThemeNotFoundException($theme);
        }

        $this->loadTheme($theme);
    }
public function set($theme)
    {
        if (!$this->has($theme)) {
            throw new ThemeNotFoundException($theme);
        }

        $this->loadTheme($theme);
    }
Set current active theme

@param string $theme Theme directory
@throws ThemeNotFoundException