TableView: Tự động tính lại chiều cao của tableview theo nội dung của nó

Việc co dãn, tính toán chiều cao của table view một cách tự động sẽ thường xuyên gặp trong qúa trình lập trình.

Hôm nay tôi sẽ chỉ cho bạn một phương pháp tuyệt vời để thực hiện điều này:

1 - Cài đặt height constraint từ storyboard .
2 - Kéo height constraint từ storyboard và tạo @IBOutlet cho nó trong file View Controller.

 @IBOutlet weak var tableHeight: NSLayoutConstraint!

3 -Thêm đoạn code sau vào viewWillLayoutSubviews()

override func viewWillLayoutSubviews() {
    super.updateViewConstraints()
    self.tableHeight?.constant = self.table.contentSize.height
}

Nếu row cuối bị cut khi hiển thị, bạn hãy gọi viewWillLayoutSubviews() trong hàm willDisplay:

func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {
    self.viewWillLayoutSubviews()
}

That's all !!!

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