getThemeData() {
  var themeData = ThemeData(
        primarySwatch: primarySwatch
   );

    var result = themeData.copyWith(
      textTheme: confirmTextTheme(themeData.textTheme),
      accentTextTheme: confirmTextTheme(themeData.accentTextTheme),
      primaryTextTheme: confirmTextTheme(themeData.primaryTextTheme),
    );
    return result;
}
/// 处理 ios 上，同页面出现韩文和简体中文，导致的显示字体异常
confirmTextTheme(TextTheme textTheme) {
  getCopyTextStyle(TextStyle textStyle) {
    return textStyle.copyWith(fontFamilyFallback: ["PingFang SC", "Heiti SC"]);
  }

  return textTheme.copyWith(
    display4: getCopyTextStyle(textTheme.display4),
    display3: getCopyTextStyle(textTheme.display3),
    display2: getCopyTextStyle(textTheme.display2),
    display1: getCopyTextStyle(textTheme.display1),
    headline: getCopyTextStyle(textTheme.headline),
    title: getCopyTextStyle(textTheme.title),
    subhead: getCopyTextStyle(textTheme.subhead),
    body2: getCopyTextStyle(textTheme.body2),
    body1: getCopyTextStyle(textTheme.body1),
    caption: getCopyTextStyle(textTheme.caption),
    button: getCopyTextStyle(textTheme.button),
    subtitle: getCopyTextStyle(textTheme.subtitle),
    overline: getCopyTextStyle(textTheme.overline),
  );
}