Tableview Rounded Corners and Shadow

UITableViewCell: rounded corners and shadow

This question comes at a good time! I literally JUST solved this same issue myself.

Create a UIView (let's refer to it as mainBackground) inside your cell's Content View. This will contain all of your cell's content. Position it and apply necessary constraints in the Storyboard.
Create another UIView. This one will be the one with the shadow (let's refer to it as shadowLayer). Position it exactly as you did mainBackground, but behind it, and apply the same constraints.

Now you should be able to set the rounded corners and the shadows as follows:

cell.mainBackground.layer.cornerRadius = 8  
cell.mainBackground.layer.masksToBounds = true

cell.shadowLayer.layer.masksToBounds = false
cell.shadowLayer.layer.shadowOffset = CGSizeMake(0, 0)
cell.shadowLayer.layer.shadowColor = UIColor.blackColor().CGColor
cell.shadowLayer.layer.shadowOpacity = 0.23
cell.shadowLayer.layer.shadowRadius = 4

However, the problem here is: calculating the shadow for every single cell is a slow task. You'll notice some serious lag when you scroll through your table. The best way to fix this is to define a UIBezierPath for the shadow, then rasterize it. So you may want to do this:

cell.shadowLayer.layer.shadowPath = UIBezierPath(roundedRect: cell.shadowLayer.bounds, byRoundingCorners: .AllCorners, cornerRadii: CGSize(width: 8, height: 8)).CGPath
cell.shadowLayer.layer.shouldRasterize = true
cell.shadowLayer.layer.rasterizationScale = UIScreen.mainScreen().scale

But this creates a new problem! The shape of the UIBezierPath depends on shadowLayer's bounds, but the bounds are not properly set by the time cellForRowAtIndexPath is called. So, you need to adjust the shadowPath based on shadowLayer's bounds. The best way to do this is to subclass UIView, and add a property observer to the bounds property. Then set all the properties for the shadow in didSet. Remember to change the class of your shadowLayer in the storyboard to match your new subclass.

class ShadowView: UIView {
    override var bounds: CGRect {
        didSet {
            setupShadow()
        }
    }

    private func setupShadow() {
        self.layer.cornerRadius = 8
        self.layer.shadowOffset = CGSize(width: 0, height: 3)
        self.layer.shadowRadius = 3
        self.layer.shadowOpacity = 0.3
        self.layer.shadowPath = UIBezierPath(roundedRect: self.bounds, byRoundingCorners: .allCorners, cornerRadii: CGSize(width: 8, height: 8)).cgPath
        self.layer.shouldRasterize = true
        self.layer.rasterizationScale = UIScreen.main.scale
    }
}

TableView rounded corners and shadow

You can add your table view to a container view and add drop shadow to that container view:

let containerView:UIView = UIView(frame:CGRect(x: 10, y: 100, width: 300, height: 400))
self.tableView = UITableView(frame: containerView.bounds), style: .Plain)
containerView.backgroundColor = UIColor.clearColor()
containerView.layer.shadowColor = UIColor.darkGrayColor().CGColor   
containerView.layer.shadowOffset = CGSize(width: 2.0, height: 2.0)
containerView.layer.shadowOpacity = 1.0
containerView.layer.shadowRadius = 2
// This is for rounded corners
self.tableView.layer.cornerRadius = 10
self.tableView.layer.masksToBounds = true
self.view.addSubview(containerView)
containerView.addSubview(self.tableView)

Edit

Swift 3.0:

let containerView:UIView = UIView(frame:CGRect(x: 10, y: 100, width: 300, height: 400))
self.tableView = UITableView(frame: containerView.bounds, style: .plain)
containerView.backgroundColor = UIColor.clear
containerView.layer.shadowColor = UIColor.darkGray.cgColor
containerView.layer.shadowOffset = CGSize(width: 2.0, height: 2.0)
containerView.layer.shadowOpacity = 1.0
containerView.layer.shadowRadius = 2
    
self.tableView.layer.cornerRadius = 10
self.tableView.layer.masksToBounds = true
self.view.addSubview(containerView)
containerView.addSubview(self.tableView)

Sample Image

How to style tableview sections with shadow, padding and rounded corners?

It could be achieved by simply adding uitableview as a cell of uitableview and add the shadow and border to each cell.

Grouped table view with shadow

I messed around with this for ages, and eventually altered some Objc code to have your desired result.

I never had the will to make it work for single cells too. Always a few bugs. However for two or more cells, use this extension on the cell itself and not the contentView.

Inside cells layoutSubviews

backgroundView = UIView(frame: contentView.frame)
backgroundView?.clipsToBounds = false
backgroundView?.backgroundColor = .clear

addShadowToCellInTableView(lastIndex: lastIndex, atIndexPath: indexPath)

public extension UITableViewCell {
    /** adds a drop shadow to the background view of the (grouped) cell */
    func addShadowToCellInTableView(lastIndex: Int, atIndexPath indexPath: IndexPath!) {
        let isFirstRow: Bool = indexPath.row == 0
        let isLastRow: Bool = (indexPath.row == lastIndex - 1)

        guard let backgroundView = self.backgroundView else { return }

        let backBounds = backgroundView.bounds
        // the shadow rect determines the area in which the shadow gets drawn
        var shadowRect: CGRect = backBounds.insetBy(dx: 0, dy: -10)
        if isFirstRow {
            shadowRect.origin.y += 10
        } else if isLastRow {
            shadowRect.size.height -= 10
        }

        // the mask rect ensures that the shadow doesn't bleed into other table cells
        var maskRect: CGRect = backBounds.insetBy(dx: -20, dy: 0)
        if isFirstRow {
            maskRect.origin.y -= 10
            maskRect.size.height += 10
        } else if isLastRow {
            maskRect.size.height += 10
        }

        // now configure the background view layer with the shadow
        let layer: CALayer = backgroundView.layer
        layer.shadowColor = UIColor.black.cgColor
        layer.shadowOffset = CGSize(width: 0, height: 0)
        layer.shadowRadius = 4
        layer.shadowOpacity = 0.23
        layer.shadowPath = UIBezierPath(rect: shadowRect).cgPath
        layer.masksToBounds = false

        // and finally add the shadow mask
        let maskLayer = CAShapeLayer()
        maskLayer.path = UIBezierPath(rect: maskRect).cgPath
        layer.mask = maskLayer
    }

    func addShadowToSingleCell() {
        layer.shadowOpacity = 0.23
        layer.shadowRadius = 4
        layer.shadowOffset = CGSize(width: 0, height: 0)
        layer.shadowColor = UIColor.black.cgColor

        layer.shadowPath = UIBezierPath(roundedRect: contentView.frame,
                                        cornerRadius: contentView.layer.cornerRadius).cgPath
    }
}

Shadow does not work with round corner on top Tableview

Here is the method that will allow you to make the UIView round with shadow:

extension UIView {
  func addShadow(cornerRadius: CGFloat, maskedCorners: CACornerMask, color: UIColor, offset: CGSize, opacity: Float, shadowRadius: CGFloat) {
    self.layer.cornerRadius = cornerRadius
    self.layer.maskedCorners = maskedCorners
    self.layer.shadowColor = color.cgColor
    self.layer.shadowOffset = offset
    self.layer.shadowOpacity = opacity
    self.layer.shadowRadius = shadowRadius
  }
}

Use:
For rounding all the corners:

<your_view_object>.addShadow(cornerRadius: 10.0, maskedCorners: [.layerMaxXMaxYCorner, .layerMinXMaxYCorner, .layerMaxXMinYCorner, .layerMinXMinYCorner], color: AppColors.themeBlack.withAlphaComponent(0.6), offset: CGSize.zero, opacity: 0.4, shadowRadius: 4.0)

For rounding only top corners:

<your_view_object>.addShadow(cornerRadius: 10.0, maskedCorners: [.layerMaxXMinYCorner, .layerMinXMinYCorner], color: AppColors.themeBlack.withAlphaComponent(0.6), offset: CGSize.zero, opacity: 0.4, shadowRadius: 4.0)

For rounding only bottom corners:

<your_view_object>.addShadow(cornerRadius: 10.0, maskedCorners: [.layerMaxXMaxYCorner, .layerMinXMaxYCorner], color: AppColors.themeBlack.withAlphaComponent(0.6), offset: CGSize.zero, opacity: 0.4, shadowRadius: 4.0)

For making the shadow as per you requirement change the others parameters.