我正在使用tableView，需要通过拖放来启用交换项目。
我主要在那里，但坚持一个问题。拖动到的项目不会与拖动的项目交换。相反，新拖动的项目会添加到现有项目的顶部，而只是将现有项目向下移动一行。
case UIGestureRecognizerState.Ended:
var center = My.cellSnapshot!.center
center.y = locationInView.y
My.cellSnapshot!.center = center
if ((indexPath != nil) && (indexPath != Path.initialIndexPath)) {
//check to see if this is a valid place to swap
var numberOfSlots:Int = 0 //the number of valid positions to swap
numberOfSlots = thePlayers[Path.initialIndexPath!.row].SwapPosition.count
for index in 1...numberOfSlots {
if thePlayers[Path.initialIndexPath!.row].SwapPosition[index - 1] == thePlayers[indexPath!.row].PlayerPosition {
//this is a valid swap
print("Swap it!")
OkToSwap = true
break
}
else {
print (thePlayers[Path.initialIndexPath!.row].SwapPosition[index - 1])
}
}
}
if OkToSwap == true { //if this is a valid slot for a swap, then swap it.
// swap(&itemsArray[indexPath!.row], &itemsArray[Path.initialIndexPath!.row])
//***TODO: Add Webservice call to swap on the website***
//move the selectedRow to the original (dragged from) position
tableView.moveRowAtIndexPath(Path.initialIndexPath!, toIndexPath: indexPath!)
My.cellSnapshot?.alpha = 0.0
let cell = tableView.cellForRowAtIndexPath(Path.initialIndexPath!) as UITableViewCell!
cell.alpha = 1
}
//put it back
let cell = tableView.cellForRowAtIndexPath(indexPath!) as UITableViewCell!
cell.hidden = false
cell.alpha = 0.0
UIView.animateWithDuration(0.25, animations: { () -> Void in
My.cellSnapshot!.center = originalCenter
My.cellSnapshot!.transform = CGAffineTransformIdentity
My.cellSnapshot!.alpha = 0.0
cell.alpha = 1.0
}, completion: { (finished) -> Void in
if finished {
Path.initialIndexPath = nil
My.cellSnapshot!.removeFromSuperview()
My.cellSnapshot = nil
}
})
default:
let cell = tableView.cellForRowAtIndexPath(Path.initialIndexPath!) as UITableViewCell!
cell.hidden = false
cell.alpha = 0.0
// Clean up.
UIView.animateWithDuration(0.25, animations: { () -> Void in
My.cellSnapshot!.center = cell.center
My.cellSnapshot!.transform = CGAffineTransformIdentity
My.cellSnapshot!.alpha = 0.0
cell.alpha = 1.0
}, completion: { (finished) -> Void in
if finished {
Path.initialIndexPath = nil
My.cellSnapshot!.removeFromSuperview()
My.cellSnapshot = nil
}
})
}
}
任何想法如何使用Swift 2.0进行真正的行交换 - 我发现了一些示例代码片段，但语法更改使它们无法工作而且我被卡住了。
答案 0 :(得分：1)
我能够使用Swift 2.0
func snapshopOfCell(inputView: UIView) -> UIView {
UIGraphicsBeginImageContextWithOptions(inputView.bounds.size, false, 0.0)
inputView.layer.renderInContext(UIGraphicsGetCurrentContext())
let image = UIGraphicsGetImageFromCurrentImageContext() as UIImage
UIGraphicsEndImageContext()
let cellSnapshot : UIView = UIImageView(image: image)
cellSnapshot.layer.masksToBounds = false
cellSnapshot.layer.cornerRadius = 0.0
cellSnapshot.layer.shadowOffset = CGSizeMake(-5.0, 0.0)
cellSnapshot.layer.shadowRadius = 5.0
cellSnapshot.layer.shadowOpacity = 0.4
return cellSnapshot
}
// MARK: Gesture Methods
func longPressGestureRecognized(gestureRecognizer: UIGestureRecognizer) {
let longPress = gestureRecognizer as! UILongPressGestureRecognizer
let state = longPress.state
var locationInView = longPress.locationInView(tableView)
var indexPath = tableView.indexPathForRowAtPoint(locationInView)
struct My {
static var cellSnapshot : UIView? = nil
}
struct Path {
static var initialIndexPath : NSIndexPath? = nil
}
switch state {
case UIGestureRecognizerState.Began:
if indexPath != nil {
Path.initialIndexPath = indexPath
let cell = tableView.cellForRowAtIndexPath(indexPath!) as UITableViewCell!
My.cellSnapshot = snapshopOfCell(cell)
var center = cell.center
My.cellSnapshot!.center = center
My.cellSnapshot!.alpha = 0.0
tableView.addSubview(My.cellSnapshot!)
UIView.animateWithDuration(0.25, animations: { () -> Void in
center.y = locationInView.y
My.cellSnapshot!.center = center
My.cellSnapshot!.transform = CGAffineTransformMakeScale(1.05, 1.05)
My.cellSnapshot!.alpha = 0.98
cell.alpha = 0.0
}, completion: { (finished) -> Void in
if finished {
cell.hidden = true
}
})
}
break
case UIGestureRecognizerState.Changed:
var center = My.cellSnapshot!.center
center.y = locationInView.y
My.cellSnapshot!.center = center
if ((indexPath != nil) && (indexPath != Path.initialIndexPath)) {
//------=-=-=-=[
// This line errors when it is uncommented. When I comment it out, the error is gone,
// and the cells /do/ reorder.. ¯\_(ツ)_/¯
//swap(&itemsArray[indexPath!.row], &itemsArray[Path.initialIndexPath!.row])
tableView.moveRowAtIndexPath(Path.initialIndexPath!, toIndexPath: indexPath!)
Path.initialIndexPath = indexPath
}
break
default:
let cell = tableView.cellForRowAtIndexPath(Path.initialIndexPath!) as UITableViewCell!
cell.hidden = false
cell.alpha = 0.0
UIView.animateWithDuration(0.25, animations: { () -> Void in
My.cellSnapshot!.center = cell.center
My.cellSnapshot!.transform = CGAffineTransformIdentity
My.cellSnapshot!.alpha = 0.0
cell.alpha = 1.0
}, completion: { (finished) -> Void in
if finished {
Path.initialIndexPath = nil
My.cellSnapshot!.removeFromSuperview()
My.cellSnapshot = nil
}
})
break
}//.switch
}// .longPressGestureRecognized