Instantaneous data transfer to custom cell from viewcontroller - ios

Question

I'm trying to activate a function inside my custom cell by setting the value of a boolean inside the custom cell class. This is my best attempt at doing this:
func blurViewActive(gestureRecognizer:UIGestureRecognizer) {
if (gestureRecognizer.state == UIGestureRecognizerState.Began) {
println("STATE BEGAN")
var point = gestureRecognizer.locationInView(self.tv)
if let indexPath = self.tv.indexPathForRowAtPoint(point) {
let data = messageList[indexPath.row] as Messages
let mcell: TableViewCell = self.tv.dequeueReusableCellWithIdentifier("cell") as TableViewCell
mcell.read = true
}
}
}
but this doesn't work, and I really have no idea how to do this any other way.
Here is the code for my custom cell class:
class TableViewCell: UITableViewCell, UIGestureRecognizerDelegate {
#IBOutlet weak var labelOutl: UILabel!
var timer = NSTimer()
var counter = 10
var read = Bool()
#IBOutlet weak var dateLabel: UILabel!
override func awakeFromNib() {
super.awakeFromNib()
if read == true{
println("hello")
}
}
override func setSelected(selected: Bool, animated: Bool) {
super.setSelected(selected, animated: animated)
}
func timerStarted(){
timer = NSTimer.scheduledTimerWithTimeInterval(1, target: self, selector: "update", userInfo: nil, repeats: true)
}
func update(){
println(--counter)
}
}
My expected outcome is that once read has been set to "true" in my view controller, the function inside awakeFromNib-function should be executed instantaneously.

Answer 1

There seems to be a number of points of confusion here.
dequeueReusableCellWithIdentifier returns a cell for use in the table view it is called on. This will be either a newly instantiated cell or an existing cell not currently displayed in any of the table's visible rows. Setting the read property on this cell will therefore have no immediate visible effect.
If you want access to a visible cell you could use cellForRowAtIndexPath but even then changes made to that cell will not necessarily update the UI. Instead you probably want to update whatever model backs that cell and call reloadRowsAtIndexPaths to update a specific cell.
Additionally awakeFromNib will be called only when a new cell is created. That will be before it is returned from dequeueReusableCellWithIdentifier and therefore well before you can take any action on it, like setting its read property. It will also not be called once per row in your table or per displayed row since you are using a reuse identifier. Instead the table view will create at least one cell for each visible row and reuse them as row scroll into and out of sight. This is convenient because minimizing the number of objects created helps reduce memory use and reduces load which could slow down scrolling performance. However it means that your data source needs to be prepared to update these cells as they are reused from one row to the next.