How to prevent highlighting of table row in next segment? - ios

Question

When I select a table row and click 'Ok' under city tab, it is highlighting the row but when I change the tab to town, it is highlighting the same row in the town tab even though I did not select it.That is if I highlight second and third row under city tab, it is highlighting second and third row under town tab as well without me doing anything. Following is my code
public func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell{
let myCell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! CityCell
switch (segCtrl.selectedSegmentIndex)
{
case 0:
myCell.myLabel.text = cityName[indexPath.row]
break
case 1:
myCell.myLabel.text = townName[indexPath.row]
break
default:break
}
return myCell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath){
let cell = tableView.cellForRow(at: indexPath)!
let alertController = UIAlertController(title: nil, message: nil, preferredStyle: .alert)
let ok = UIAlertAction(title: "Ok", style: .default, handler: { (action) -> Void in
let cell = tableView.cellForRow(at: indexPath)!
cell.backgroundColor = UIColor(white: 1.0, alpha:0.5)
})
let cancel = UIAlertAction(title: "Cancel", style: .cancel, handler: { (action) -> Void in
})
alertController.addAction(ok)
alertController.addAction(cancel)
present(alertController, animated: true, completion: nil)
}
How do I prevent this highlighting from happening in next tab and confine it to where I actually selected the row?

Answer 1

I'm working with objective-c. So, sorry if my swift code is wrong.
// global variable which carry selection-indexPath
var citySelectedIndexPaths = [IndexPath]()
var townSelectedIndexPaths = [IndexPath]()
public func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell{
let myCell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as! CityCell
// add this line
myCell.backgroundColor = UIColor(white: 1.0, alpha:1.0) // default color
switch (segCtrl.selectedSegmentIndex)
{
case 0:
myCell.myLabel.text = cityName[indexPath.row]
if citySelectedIndexPaths.contains(indexPath) {
myCell.backgroundColor = UIColor(white: 1.0, alpha:0.5)
}
break
case 1:
myCell.myLabel.text = townName[indexPath.row]
if townSelectedIndexPaths.contains(indexPath) {
myCell.backgroundColor = UIColor(white: 1.0, alpha:0.5)
}
break
default:break
}
return myCell
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath){
let cell = tableView.cellForRow(at: indexPath)!
let alertController = UIAlertController(title: nil, message: nil, preferredStyle: .alert)
let ok = UIAlertAction(title: "Ok", style: .default, handler: { (action) -> Void in
let cell = tableView.cellForRow(at: indexPath)!
cell.backgroundColor = UIColor(white: 1.0, alpha:0.5)
// save selection indexPath
switch (segCtrl.selectedSegmentIndex)
{
case 0:
if citySelectedIndexPaths.contains(indexPath) {
let indexValue = citySelectedIndexPaths.indexOf(indexPath)
citySelectedIndexPaths.removeAtIndex(indexValue)
} else {
citySelectedIndexPaths.append(indexPath);
}
break
case 1:
if townSelectedIndexPaths.contains(indexPath) {
let indexValue = townSelectedIndexPaths.indexOf(indexPath)
townSelectedIndexPaths.removeAtIndex(indexValue)
} else {
townSelectedIndexPaths.append(indexPath);
}
break
default:break
}
})
let cancel = UIAlertAction(title: "Cancel", style: .cancel, handler: { (action) -> Void in
})
alertController.addAction(ok)
alertController.addAction(cancel)
present(alertController, animated: true, completion: nil)
}

Answer 2

Now in your code, you set background manually.
cell.backgroundColor = UIColor(white: 1.0, alpha:0.5)
But you did not reset cell.backgroundColor after you select other cell. So you need to store current selected cell's indexPath and call reloadData each time you select new cell in ok UIAlertAction. In cellForRowAtIndexPath, just perform cell with selected or unselected stage.