Android theme name from theme ID

Using packageInfo.applicationInfo.theme will return the theme for the entire app and not each activity. This is hacky, but should get the theme for the current activity/context:

java

public static String getThemeName(Context context, Resources.Theme theme) {
  try {
    int mThemeResId;
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
      Field fThemeImpl = theme.getClass().getDeclaredField("mThemeImpl");
      if (!fThemeImpl.isAccessible()) fThemeImpl.setAccessible(true);
      Object mThemeImpl = fThemeImpl.get(theme);
      Field fThemeResId = mThemeImpl.getClass().getDeclaredField("mThemeResId");
      if(!fThemeResId.isAccessible())fThemeResId.setAccessible(true);
      mThemeResId = fThemeResId.getInt(mThemeImpl);
    } else {
      Field fThemeResId = theme.getClass().getDeclaredField("mThemeResId");
      if(!fThemeResId.isAccessible())fThemeResId.setAccessible(true);
      mThemeResId = fThemeResId.getInt(theme);
    }
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
      return theme.getResources().getResourceEntryName(mThemeResId);
    }
    return context.getResources().getResourceEntryName(mThemeResId);
  } catch (Exception e) {
    // Theme returned by application#getTheme() is always Theme.DeviceDefault
    return "Theme.DeviceDefault";
  }
}

I know this is an old question, but thought I would add my findings.