在拖动表格之前,在UITableView中显示滚动条.在某种程度上,UIScrollBar应始终可见

Question

我在我的应用程序中使用了几个UITableView.其中一些包含几行,而一些只有两个.我需要的是:如果表包含多行,那么在用户甚至拖动表格之前,滚动条应该是可见的.或者换句话说,是否可以使滚动条始终可见？

Answer 1

您可以闪烁它们,但没有选项让它们始终可见:

[ScrollView flashScrollIndicators];

UITableView是UIScrollView的子类,因此您可以直接使用它

  - (void)viewDidAppear:(BOOL)animated {
      [super viewDidAppear:animated];
      [self.tableView performSelector:@selector(flashScrollIndicators) withObject:nil afterDelay:0];
}

查看更多信息: UIScrollView - 显示滚动条

迅速:

override func viewDidAppear(animated: Bool) {
    super.viewDidAppear(animated)
    self.tableView.flashScrollIndicators()   
}

Answer 2

Swift 3.0

1)计时器

var timerForShowScrollIndicator: Timer?

2)方法

/// Show always scroll indicator in table view
func showScrollIndicatorsInContacts() {
    UIView.animate(withDuration: 0.001) {
        self.tableView.flashScrollIndicators()
    }
}

/// Start timer for always show scroll indicator in table view
func startTimerForShowScrollIndicator() {
    self.timerForShowScrollIndicator = Timer.scheduledTimer(timeInterval: 0.3, target: self, selector: #selector(self.showScrollIndicatorsInContacts), userInfo: nil, repeats: true)
}

/// Stop timer for always show scroll indicator in table view
func stopTimerForShowScrollIndicator() {
    self.timerForShowScrollIndicator?.invalidate()
    self.timerForShowScrollIndicator = nil
}

3)使用

startTimerForShowScrollIndicator在viewDidAppear

stopTimerForShowScrollIndicator在viewDidDisappear