快速将TableView数据传递给DetailViewController

Question

I have a simple tableview loading with array of colours(each cell with different colour).i am trying to pass the background colour of detailViewController when user press the colour array cell from colourTableviewcontroller(simply i want to pass the cell colour as a detailview background colour) my code as follows.....

import UIKit 

class colourTableviewcontroller: UITableViewController {

@IBOutlet weak var colorTableView: UITableView!

let colors = [UIColor.redColor(), UIColor.blueColor(),UIColor.greenColor(), UIColor.orangeColor(),UIColor.purpleColor(),UIColor.yellowColor(),UIColor.cyanColor(),UIColor.darkGrayColor(),UIColor.blackColor(), UIColor.brownColor(),UIColor.grayColor(), UIColor.magentaColor(), UIColor.whiteColor()]

var colourData = UIColor()

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

override func viewDidAppear(animated: Bool) {
   colorTableView.separatorColor = UIColor.clearColor()
}

override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
    return 1
}

override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return colors.count
}

override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

    let cell = tableView.dequeueReusableCellWithIdentifier("colourCell", forIndexPath: indexPath) as UITableViewCell

    cell.backgroundColor = self.colors[indexPath.row % self.colors.count]

    return cell

}

override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {

    colourData = self.colors[indexPath.row]
    performSegueWithIdentifier("colourSegue", sender: self)

}

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {

    if (segue.identifier == "colourSegue") {

 let viewController = segue.destinationViewController as! DetailViewController

 viewController.bc?.backgroundColor = colourData }
}}                  

 // My DetailViewController as follows...
 import UIKit
 class DetailViewController: UIViewController {
 @IBOutlet var bc: UIView!

 override func viewDidLoad() {
 self.bc.backgroundColor = UIView.appearance().backgroundColor
 }

when i run the code my DetailViewController background colour changing to dark text colour when i press the colour array.....

i don't know what i am missing or am i doing wrong approach/logic....

Thanks in Advance.....

Answer 1

• First of all in ColourTableviewcontroller connect the segue to the table view cell rather than to the view controller and delete the method didSelectRowAtIndexPath

• Replace prepareForSegue with

   override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) { if segue.identifier == "colourSegue" { let viewController = segue.destinationViewController as! DetailViewController let selectedIndexPath = tableView.indexPathForCell(sender as! UITableViewCell) viewController.color = colors[selectedIndexPath.row] } } 

• In DetailViewController declare a variable color

   var color : UIColor! 

• And set the color of bc in viewDidLoad()

   bc.backgroundColor = color 

The reason for the additional variable is that the IBOutlets in DetailViewController don't exist yet while prepareForSegue is executed.

Answer 2

You aren't passing the UIColor and assigning it in the next View Controller

You just need to do few modifications to your existing code

1) Add var recievedColor : UIColor! in the DetailViewController

2) In your prepareForSegue replace viewController.bc?.backgroundColor = colourData with viewController.recievedColor = colourData

3) In your DetailViewController, in viewDidLoad() function, replace self.bc.backgroundColor = UIView.appearance().backgroundColor with self.bc.backgroundColor = recievedColor

And there you go!

Answer 3

You need to pass the color, then assign the color to the view on the viewDidLoad() . You are assigning a variable to a view that hasn't been initialized yet.

in your detail class do as follow:

 class DetailViewController: UIViewController {
 @IBOutlet var bc: UIView!
 var selectedBackgroundColor: UIColor? // this should be set on the prepareForSegue method.

 override func viewDidLoad() {
   super.viewDidLoad()

   if let selectedBackgroundColor = selectedBackgroundColor {
     bc.backgroundColor = selectedBackgroundColor
   }     
 }

Hope this helps!