当滚动超过内容的50%时,将新数据添加到tableview
,但问题是添加滚动后将内容移动到顶部,如何保存位置并滚动?更改了从底部开始的表格的显示内容
func scrollViewDidEndDragging(_ scrollView: UIScrollView, willDecelerate decelerate: Bool) {
if (self.lastContentOffset > scrollView.contentOffset.y && loadEarlierShowF) {
let height = scrollView.frame.size.height
let cHeight = scrollView.contentSize.height
let contentYoffset = scrollView.contentOffset.y
let distanceFromBottom = scrollView.contentSize.height - contentYoffset
print(distanceFromBottom)
let eght = cHeight / 100 * 50
if distanceFromBottom >= eght {
actionLoadEarlier()
}
}
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
if (indexPath.row == 0) {
let cell = tableView.dequeueReusableCell(withIdentifier: "RCSectionHeaderCell", for: indexPath) as! RCSectionHeaderCell
cell.bindData(indexPath, messagesView: self)
return cell
}
if (indexPath.row == 1) {
let cell = tableView.dequeueReusableCell(withIdentifier: "RCBubbleHeaderCell", for: indexPath) as! RCBubbleHeaderCell
cell.bindData(indexPath, messagesView: self)
return cell
}
if (indexPath.row == 2) {
let rcmessage = self.rcmessage(indexPath)
if (rcmessage.type == RC_TYPE_STATUS) {
let cell = tableView.dequeueReusableCell(withIdentifier: "RCStatusCell", for: indexPath) as! RCStatusCell
cell.bindData(indexPath, messagesView: self)
return cell
}
if (rcmessage.type == RC_TYPE_TEXT) {
let cell = tableView.dequeueReusableCell(withIdentifier: "RCTextMessageCell", for: indexPath) as! RCTextMessageCell
cell.bindData(indexPath, messagesView: self)
let numSections = self.tableView.numberOfSections
if numSections == 1 {
updateTableContentInset()
}
return cell
}
}
if (indexPath.row == 3) {
let cell = tableView.dequeueReusableCell(withIdentifier: "RCBubbleFooterCell", for: indexPath) as! RCBubbleFooterCell
cell.bindData(indexPath, messagesView: self)
return cell
}
if (indexPath.row == 4) {
let cell = tableView.dequeueReusableCell(withIdentifier: "RCSectionFooterCell", for: indexPath) as! RCSectionFooterCell
cell.bindData(indexPath, messagesView: self)
return cell
}
return UITableViewCell()
}
func updateTableContentInset() {
let numSections = self.tableView.numberOfSections
var contentInsetTop = self.tableView.bounds.size.height
for section in 0..<numSections {
let numRows = self.tableView.numberOfRows(inSection: section)
let sectionHeaderHeight = self.tableView.rectForHeader(inSection: section).size.height
let sectionFooterHeight = self.tableView.rectForFooter(inSection: section).size.height
contentInsetTop -= sectionHeaderHeight + sectionFooterHeight
for i in 0..<numRows {
let rowHeight = self.tableView.rectForRow(at: IndexPath(item: i, section: section)).size.height
contentInsetTop -= rowHeight
if contentInsetTop <= 0 {
contentInsetTop = 0
break
}
}
if contentInsetTop == 0 {
break
}
}
self.scrollView.contentInsetAdjustmentBehavior = .never
self.tableView.contentInsetAdjustmentBehavior = .never
self.tableView.contentInset = UIEdgeInsetsMake(contentInsetTop, 0, 0, 0)
}
如何做到这一点将添加新的数据和滚动数据的内容保持在原位(例如电报)
已经尝试过,但不是在那里转移
let offset = tableView.contentOffset
tableView.reloadData()
tableView.layoutIfNeeded()
tableView.setContentOffset(offset, animated: false)
....
let indexPath = IndexPath(row: 2, section: tableView.numberOfSections - 1)
tableView.reloadData()
tableView.layoutIfNeeded()
tableView.scrollToRow(at: indexPath, at: .top, animated: false)
为什么你可以尝试这个?
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableTest.dequeueReusableCell(withIdentifier: "cell", for: indexPath)
cell.textLabel?.text = arrayTemp[indexPath.row]
if indexPath.row > (arrayTemp.count / 2) {
callNewData()
}
return cell
}
您可以使用表中加载的索引来添加更多值。
加载单元格时,可以调用该函数向表视图添加更多数据,因此如果数据在加载5单元格时以10个值开始,则在数组temp中添加10个itens,这样现在数组有20个值, table加载索引10你调用更多itens。