如何滚动到 UITableView 中最后一节的最后一行？

Question

So I have a UITableView that fetches data from an array of an object say Chats . To scroll to the last row of this array I know that we use:

var chats = [Chats]()
self.tableView.scrollToRow(at: [0, self.chats.count - 1], at: .bottom, animated: true)

What if I have an array of array (This is so that I can group chat messages into sections based on date). Now I have sections and then rows under that section.

var groupedChats = [[Chats]]()

How do I scroll to the last row of the last section?

Answer 1

Try this

    let lastSection = groupedChats.count-1
    let lastRow = groupedChats[lastSection].count-1
    if lastSection >= 0, lastRow >= 0 {
        self.tableView.scrollToRow(at: IndexPath(row: lastRow, section: lastSection), at: .bottom, animated: true)
    }

Answer 2

Finding the last section and last row, and scroll to last rows indexpath.

Swift 5:

let lastSection = tableView.numberOfSections - 1
let lastRow = tableView!.numberOfRows(inSection: lastSection)
let lastRowIndexPath = IndexPath(row: lastRow, section: lastSection)
tableView.scrollToRow(at: lastRowIndexPath, at: .top, animated: true)

Answer 3

 func scrollToBottom(_ animated: Bool = true) {
        let numberOfSections = self.tblView.numberOfSections
        if numberOfSections > 0 {
            let numberOfRows = self.tblView.numberOfRows(inSection: numberOfSections - 1)
            if numberOfRows > 0 {
                let indexPath = IndexPath(row: numberOfRows - 1, section: (numberOfSections - 1))
                self.tblView.scrollToRow(at: indexPath, at: .bottom, animated: animated)
            }
        }
    }

Answer 4

Better create an extension for reusability:

extension UITableView {

    func scrollToBottom(){

        DispatchQueue.main.async {
            let indexPath = IndexPath(
                row: self.numberOfRows(inSection:  self.numberOfSections-1) - 1,
                section: self.numberOfSections-1)
            self.scrollToRow(at: indexPath, at: .bottom, animated: true)
        }
    }
}

Answer 5

You can try this,

let lastSectionIndex = self.groupedChats.numberOfSections - 1 // last section
let lastRowIndex = self.groupedChats.numberOfRows(inSection: lastSectionIndex) - 1 // last row
self.tableView.scrollToRow(at: IndexPath(row: lastRowIndex, section: lastSectionIndex), at: .Bottom, animated: true)