Empty UITableView with tableFooterView - ios

Question

I have a UITableView in which I want to show a message when the dataSource is empty. I do this with the well-known method of setting the backgroundView using the following extension:
extension UITableView {
func setEmptyMessage(_ message: String, _ image: String) {
let emptyView: UIView = {
let emptyView = UIView(frame: CGRect(x: 0, y: 0, width: self.frame.size.width, height: self.frame.size.height))
return emptyView
}()
let contentView: UIView = {
let contentView = UIView()
contentView.translatesAutoresizingMaskIntoConstraints = false
return contentView
}()
let messageLabel = UILabel()
let messageCommentStyle = NSMutableParagraphStyle()
messageCommentStyle.lineHeightMultiple = 1.2
let attributedString = NSMutableAttributedString(string: message)
attributedString.addAttribute(NSAttributedString.Key.foregroundColor, value: lightFeedUserNameFontColor, range: NSRange(location: 0, length: attributedString.length))
attributedString.addAttribute(NSAttributedString.Key.paragraphStyle, value: messageCommentStyle, range: NSRange(location: 0, length: attributedString.length))
attributedString.addAttribute(NSAttributedString.Key.font, value: UIFont.systemFont(ofSize: normalFontSize), range: NSRange(location: 0, length: attributedString.length))
messageLabel.attributedText = attributedString
messageLabel.numberOfLines = 0
messageLabel.font = UIFont.systemFont(ofSize: normalFontSize)
messageLabel.textAlignment = .center
messageLabel.sizeToFit()
messageLabel.translatesAutoresizingMaskIntoConstraints = false
let errorImage: UIImageView = {
let errorImage = UIImageView()
errorImage.translatesAutoresizingMaskIntoConstraints = false
return errorImage
}()
self.backgroundView = emptyView
emptyView.addSubview(contentView)
contentView.addSubview(errorImage)
contentView.addSubview(messageLabel)
contentView.centerYAnchor.constraint(equalTo: emptyView.centerYAnchor).isActive = true
contentView.centerXAnchor.constraint(equalTo: emptyView.centerXAnchor).isActive = true
contentView.leadingAnchor.constraint(equalTo: emptyView.leadingAnchor, constant: normalSpacing * 3).isActive = true
contentView.trailingAnchor.constraint(equalTo: emptyView.trailingAnchor, constant: -(normalSpacing * 3)).isActive = true
contentView.topAnchor.constraint(equalTo: errorImage.topAnchor).isActive = true
contentView.bottomAnchor.constraint(equalTo: messageLabel.bottomAnchor).isActive = true
messageLabel.leadingAnchor.constraint(equalTo: contentView.leadingAnchor).isActive = true
messageLabel.trailingAnchor.constraint(equalTo: contentView.trailingAnchor).isActive = true
messageLabel.centerYAnchor.constraint(equalTo: contentView.centerYAnchor).isActive = true
}
func restore() {
self.backgroundView = nil
}
}
And I set it like this:
if(tableData.isEmpty) {
self.tableView.setEmptyMessage("No results!", "none")
} else {
self.tableView.restore()
}
self.tableView.reloadData()
No big deal, we all have seen this and probably used it. And it works great. However, I now have a UIButton on the bottom placed in the tableFooterView. This button stays on top of the UITableView because it automatically positions itself right under the last cell, which is precisely what I want when there is data, but now the empty message is shown in the middle of the screen while the button is above it. How can I fix this so there is a sort of frame when the dataSource is empty?
To illustrate:

Answer 1

So now you are setting your tableView backgroundView to your emptyView. You can take a look on your dataSource and if it's empty - just return new cell for empty state with this message.
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return dataSource.count > 0 ? dataSource.count : 1
}
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
if dataSource.count.isEmpty 0 {
let cell = tableView.dequeueReusableCell(withIdentifier: "EmptyCell")
cell.textLabel.text = "No Results!"
return cell
} else {
let cell = tableView.dequeueReusableCell(withIdentifier: "SomeCell")
return cell
}
}

Answer 2

Write an extension
extension UITableView
{
func addErrorMessageLabel(noDataText:String = "No data available")->UILabel
{
let noDatalabel:UILabel!
noDatalabel=UILabel(frame: CGRect(x: self.frame.size.width/2-200, y: self.frame.size.height/2-50, width: 400, height: 100))
noDatalabel.textColor = textThemeColor
noDatalabel.text=noDataText
noDatalabel.numberOfLines=0
noDatalabel.textAlignment = .center
noDatalabel.isHidden=true
self.addSubview(noDatalabel)
self.alignCenterToSuperView(item: noDatalabel, horizentally: true, vertically: true,height: 100,width: 400)
return noDatalabel
}
func alignCenterToSuperView(item:UIView,horizentally:Bool,vertically:Bool , height:Int, width:Int)
{
if horizentally
{
item.translatesAutoresizingMaskIntoConstraints = false
let xConstraint = NSLayoutConstraint(item: item, attribute: .centerX, relatedBy: .equal, toItem: self, attribute: .centerX, multiplier: 1, constant: 0)
NSLayoutConstraint.activate([xConstraint])
}
if vertically
{
item.translatesAutoresizingMaskIntoConstraints = false
let yConstraint = NSLayoutConstraint(item: item, attribute: .centerY, relatedBy: .equal, toItem: self, attribute: .centerY, multiplier: 1, constant: 0)
NSLayoutConstraint.activate([yConstraint])
}
let Height = NSLayoutConstraint(item: item, attribute: .height, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1, constant:CGFloat(height))
item.addConstraint(Height)
let Width = NSLayoutConstraint(item: item, attribute: .width, relatedBy: .equal, toItem: nil, attribute: .notAnAttribute, multiplier: 1, constant:CGFloat(width))
item.addConstraints([Width,Height])
}
}
In your ViewController create
var noDataLabel:UILabel!
In your ViewDidLoad
override func viewDidLoad() {
super.viewDidLoad()
noDataLabel = tableView.addErrorMessageLabel()
noDataLabel.text = "No data found" // or your message
}
And final step
if(tableData.isEmpty) {
noDataLabel.isHideen = false
} else {
noDataLabel.isHideen = true
}