如何为Xamarin iOS中从底部到顶部的UITableViewCell过渡设置动画？

Question

How to animate a UITableViewCell transition from bottom to the top in Xamarin iOS native?

Hi all community of Xamarin iOS native, I'm searching a way to animate a UITableViewCell in a UITableView, create a transition from bottom to the top with a fade effect for any cell.

Because all the examples that I find are in Swift, I solve this answer for my own I will share the solution for the community.

Answer 1

in the table source add the fallowing code

public override void WillDisplay(UITableView tableView,
UITableViewCell cell, NSIndexPath indexPath)
    {
            cell.Alpha = 0;

            var transform = CoreAnimation.CATransform3D.MakeTranslation(0, 100, 0);
            cell.Layer.Transform = transform;

            double delay = indexPath.Row * 0.2;

            UIView.Animate(1, delay, UIViewAnimationOptions.TransitionFlipFromBottom,
               () =>
               {
                   cell.Alpha = 1;
                   cell.Layer.Transform = CoreAnimation.CATransform3D.Identity;
               },finished => { }
              );

    }

you can play with this values CoreAnimation.CATransform3D.MakeTranslation(x, y, z); XYZ to create the animation that you want with the transition.

---

double delay = indexPath.Row * 0.2; I create a delay for the rows that show a little delay when show de cell for the first time. you can create your animation without the delay adding a value of 0.

cell.Alpha = 0;

this other line permit hide the cell and when the animation start the cell appearing with a fade effect.

UIView.Animate(1, delay, UIViewAnimationOptions.TransitionFlipFromBottom,
               () =>
               {
                cell.Alpha = 1;
               },
                finished => { }
              );

Answer 2

Swift 4 and fix scroll issue:

private var finishedLoadingInitialTableCells = false
override func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {

    var lastInitialDisplayableCell = false

    //change flag as soon as last displayable cell is being loaded (which will mean table has initially loaded)
    if favorites.itemes.count > 0 && !finishedLoadingInitialTableCells {
        if let indexPathsForVisibleRows = tableView.indexPathsForVisibleRows,
            let lastIndexPath = indexPathsForVisibleRows.last, lastIndexPath.row == indexPath.row {
            lastInitialDisplayableCell = true
        }
    }

    if !finishedLoadingInitialTableCells {

        if lastInitialDisplayableCell {
            finishedLoadingInitialTableCells = true
        }

        //animates the cell as it is being displayed for the first time
        do {
            let startFromHeight = tableView.frame.height
            cell.layer.transform = CATransform3DMakeTranslation(0, startFromHeight, 0)
            let delay = Double(indexPath.row) * 0.2

            UIView.animate(withDuration: 0.7, delay: delay, options: UIViewAnimationOptions.transitionFlipFromBottom, animations: {
                do {
                    cell.layer.transform = CATransform3DIdentity
                }
            }) { (success:Bool) in

            }
        }
    }
}

Answer 3

Swift 4:

override func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {
    do {
        let startFromHeight = tableView.frame.height
        cell.layer.transform = CATransform3DMakeTranslation(0, startFromHeight, 0)
        let delay = Double(indexPath.row) * 0.2

        UIView.animate(withDuration: 0.7, delay: delay, options: UIViewAnimationOptions.transitionFlipFromBottom, animations: {
            do {
                cell.layer.transform = CATransform3DIdentity
            }
        }) { (success:Bool) in

        }
    }
}