Swift animate UITableViewCell expanding height constraint [duplicate]

Question

I have a TableView with a static cell inside which I would like to expand when a button has been pressed. There is a container view inside the cell, the constraints have been set up correctly but I am not sure how to actually animate the cell expanding as it requires me to refresh the table view to update the constraints and expand the cell.

Currently when I call expandContainerView it doesn't animate, because I am calling self.tableView.reloadData.

Here is the code that I have used to expand the cell

@objc private func expandContainerView(notification: NSNotification) {

    self.view.layoutIfNeeded()

    UIView.animate(withDuration: 2.0, delay: 0.0, options: .curveEaseOut, animations: {
        self.containerHeightConstraint.constant = 410
        self.view.layoutIfNeeded()
        self.tableView.reloadData()
    }, completion: nil)
}

And here is my height for each row at index code

override func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {

    return UITableViewAutomaticDimension
}

Obtest

what actually you tring to do? Do you have expand collapse tableview or there is an another concept? – Sorenson

Answer 1

Try without an animation block:

containerHeightConstraint.constant = 410
tableView.beginUpdates()
tableView.endUpdates()

Voluble

Answer 2

You can only reload cell which you want to expand using below code. I added in the didSelectRowAt but you can add same code in button action method. Set expandCell variable to true for changing height of cell when reloading.

func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {

     // Expand View 
     self.expandCell = true 
     self.tableView.beginUpdates()
     self.tableView.reloadRows(at: [indexPath], with: UITableViewRowAnimation.automatic)
     self.tableView.endUpdates()
}

You need specify height to expand cell view else it will show default height.

func tableView(_ tableView: UITableView, heightForRowAt indexPath: IndexPath) -> CGFloat {
    if indexPath.row == expandRowIndex && self.expandCell {
         return 200
    }
    return UITableViewAutomaticDimension
} 

Note : No need of animation for this. Expansion of view animation at time of reloading cell

Anatomize

Just to add, UITableView.RowAnimation.automatic can have weird effects on the cell being expanded. If you use UITableView.RowAnimation.none instead, it will be animated and will behave normally. Very strange! – Chur