Ios FSCalendar事件点在选择日期后消失

我正在使用此代码为事件添加点，点看起来非常好，但当我选择事件发生的日期时，点会永久消失，即使选择另一天，点也不会再次出现。 这是我的代码，使点出现在开始

 func calendar(_ calendar: FSCalendar, willDisplay cell: FSCalendarCell, for date: Date, at monthPosition: FSCalendarMonthPosition) {
    let dateFormatter = DateFormatter()
    dateFormatter.dateFormat = "yyyy-MM-dd"
    let dateString = dateFormatter.string(from: date)

    cell.eventIndicator.isHidden = false

    for wp in worriesPanic{
        let wPDateStr = dateFormatter.string(from: wp.date!)
        if wPDateStr == dateString {
            cell.eventIndicator.numberOfEvents = 1
            break
        }
    }
}

You can use image method for show event.

   func calendar(_ calendar: FSCalendar, imageFor date: Date) -> UIImage? {
        let dateString = self.dateFormatter1.string(from: date)
        if self.yourDate.contains(dateString) {
            return  UIImage(named:"img")
        }
        return  nil
    }