canLaunch method

Implementation

@override
Future<bool> canLaunch(String url) async {
  final bool canLaunchSpecificUrl = await _hostApi.canLaunchUrl(url);
  if (!canLaunchSpecificUrl) {
    final String scheme = _getUrlScheme(url);
    // canLaunch can return false when a custom application is registered to
    // handle a web URL, but the caller doesn't have permission to see what
    // that handler is. If that happens, try a web URL (with the same scheme
    // variant, to be safe) that should not have a custom handler. If that
    // returns true, then there is a browser, which means that there is
    // at least one handler for the original URL.
    if (scheme == 'http' || scheme == 'https') {
      return _hostApi.canLaunchUrl('$scheme://flutter.cn');
    }
  }
  return canLaunchSpecificUrl;
}