Pass variable to custom UITableViewCell from UIViewController - ios

Question

Here is how I use my custom UITableViewCell RunningTableViewCell inside UIViewController:
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("myCell", forIndexPath: indexPath) as! RunningTableViewCell
//.......
cell.isTop = false
if(indexPath.row == 0){
cell.isTop = true
}
cell.isBottom = false
if(indexPath.row == myArray.count-1){
cell.isBottom = true
}
return cell
}
And here is my RunningTableViewCell class: (Cell's GUI is made inside storyboard)
class RunningTableViewCell: UITableViewCell {
//#IBOutlet ...
#IBOutlet weak var myButton: SomeButton!
var isTop: Bool?
var isBottom: Bool?
override func awakeFromNib() {
super.awakeFromNib()
print("result: \(self.isTop) \(self.isBottom)")
myButton.isTop = self.isTop
myButton.isBottom = self.isBottom
}
}
It returns result: nil nil
The usage of the result is: (SomeButton is a subview inside RunningTableViewCell)
class SomeButton: UIButton {
var isTop = false
var isBottom = false
override func drawRect(rect: CGRect) {
if(isTop){
// DO SOMETHING...
}
if(isBottom){
// DO SOMETHING...
}
}
}
So how can I pass data to RunningTableViewCell?

Answer 1

awakeFromNib is called right after the view and its subviews were allocated and initialized.
So your code from awakeFromNib in RunningTableViewCell for each cell is called before delegate method func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell. That is why isTop and isBottom are nil in awakeFromNib.
You can define method in RunningTableViewCell, which will load cell with this variables.
func load(isTop: Bool, isBottom: Bool) {
self.isTop = isTop
self.isBottom = isBottom
// Update cell UI as you wish
}
And finally rewrite delegate method func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell in your view controller.
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("myCell", forIndexPath: indexPath) as! RunningTableViewCell
let isTop = indexPath.row == 0
let isBottom = indexPath.row == myArray.count-1
cell.load(isTop, isBottom: isBottom)
return cell
}

Answer 2

You need to override prepareForReuse in the cell. And remove it from tableView:indexPath:. So when you scroll the cell is going to be reused but the isBotton and isTop vars will be reseted.
override func prepareForReuse() {
self.isBottom = false
self.isTop = false
}

Answer 3

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("myCell", forIndexPath: indexPath) as! RunningTableViewCell
//.......
cell.isTop = false
if(indexPath.row == 0){
cell.isTop = true
cell.tag=100
}
cell.isBottom = false
if(indexPath.row == myArray.count-1){
cell.isBottom = true
cell.tag=200
}
return cell
}
and also get this like ...
class RunningTableViewCell: UITableViewCell {
//#IBOutlet ...
var isTop: Bool?
var isBottom: Bool?
override func awakeFromNib() {
super.awakeFromNib()
if (self.tag==100)
{
isTop=true
}
else if (self.tag==200) {
isBottom=true
}
else{
isTop=false
isBottom=false
}
print("result: \(self.isTop) \(self.isBottom)")
}
}
And also do using singleton methods...

Answer 4

You can resolve this issue by call custom method in your cell like,
inside UIViewController:
//.......
cell.isTop = false
if(indexPath.row == 0){
cell.isTop = true
}
cell.isBottom = false
if(indexPath.row == myArray.count-1){
cell.isBottom = true
}
cell.UpdateViews()
return cell
}
inside TableViewCell:
//#IBOutlet ...
var isTop: Bool?
var isBottom: Bool?
func updateViews() {
print("result: \(self.isTop) \(self.isBottom)")
}
Good luck!