Swipe UITableViewCell without touch

问题:

As my title saying I want to swipe first row of UITableView left to right when user will come on that ViewController.

In my ViewController I have one UITableView, each row have two button "More" and "Delete" action. Look at below code

func tableView(_ tableView: UITableView, canEditRowAt indexPath: IndexPath) -> Bool {
    return true
}

func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCellEditingStyle, forRowAt indexPath: IndexPath) {
    if (editingStyle == UITableViewCellEditingStyle.delete) {
    }
}


func tableView(_ tableView: UITableView, editActionsForRowAt indexPath: IndexPath) -> [UITableViewRowAction]? {
    let deleteButton = UITableViewRowAction(style: .normal, title: "Delete") { action, index in
        // Edit Button Action
    }
    deleteButton.backgroundColor = UIColor.red

    let editButton = UITableViewRowAction(style: .normal, title: "Edit") { action, index in
        // Delete Button Action
    }
    editButton.backgroundColor = UIColor.lightGray

    return [deleteButton, editButton]
}

All is working good. But I want when end-user comes on this ViewController at first time so they will notify that there is swipe action available so they will perform it.

Question is: How can I do swipe left and right automatically for first row ?

What I have did?

 override func viewDidAppear(_ animated: Bool) {
    super.viewDidAppear(animated)
    let cell = posTblView.cellForRow(at: NSIndexPath(row: 0, section: 0) as IndexPath) as! POSUserTabelCell
    UIView.animate(withDuration: 0.3, animations: {
        cell.transform = CGAffineTransform.identity.translatedBy(x: -150, y: 0)
    }) { (finished) in
        UIView.animateKeyframes(withDuration: 0.3, delay: 0.25, options: [], animations: {
            cell.transform = CGAffineTransform.identity
        }, completion: { (finished) in
        })
    }
}

By above code swipe/moving cell is working but not display "Delete" and "More" button.

So please guide me on right direction.

回答1:

I found one way to achieve it.

override func viewDidAppear(_ animated: Bool) {
    super.viewDidAppear(animated)

    if arrStudent.count > 0 {
        let indexPath = NSIndexPath(row: 0, section: 0)
        let cell = tblStudent.cellForRow(at: indexPath as IndexPath);

        let swipeView = UIView()
        swipeView.frame = CGRect(x: cell!.bounds.size.width, y: 0, width: 170, height: cell!.bounds.size.height)
        swipeView.backgroundColor = .clear

        let swipeEditLabel: UILabel = UILabel.init(frame: CGRect(x: 0, y: 0, width: 80, height: cell!.bounds.size.height))
        swipeEditLabel.text = "Edit";
        swipeEditLabel.textAlignment = .center
        swipeEditLabel.font = UIFont.systemFont(ofSize: 19)
        swipeEditLabel.backgroundColor = UIColor(red: 180/255, green: 180/255, blue: 180/255, alpha: 1) // Light Gray: Change color as you want
        swipeEditLabel.textColor = UIColor.white
        swipeView.addSubview(swipeEditLabel)

        let swipeDeleteLabel: UILabel = UILabel.init(frame: CGRect(x: swipeEditLabel.frame.size.width, y: 0, width: 90, height: cell!.bounds.size.height))
        swipeDeleteLabel.text = "Delete";
        swipeDeleteLabel.textAlignment = .center
        swipeDeleteLabel.font = UIFont.systemFont(ofSize: 19)
        swipeDeleteLabel.backgroundColor = UIColor(red: 255/255, green: 41/255, blue: 53/255, alpha: 1) // Red color: Change color as you want
        swipeDeleteLabel.textColor = UIColor.white
        swipeView.addSubview(swipeDeleteLabel)

        cell!.addSubview(swipeView)

        UIView.animate(withDuration: 0.60, animations: {
            cell!.frame = CGRect(x: cell!.frame.origin.x - 170, y: cell!.frame.origin.y, width: cell!.bounds.size.width + 170, height: cell!.bounds.size.height)
        }) { (finished) in
            UIView.animate(withDuration: 0.60, animations: {
                cell!.frame = CGRect(x: cell!.frame.origin.x + 170, y: cell!.frame.origin.y, width: cell!.bounds.size.width - 170, height: cell!.bounds.size.height)

            }, completion: { (finished) in
                for subview in swipeView.subviews {
                    subview.removeFromSuperview()
                }
                swipeView.removeFromSuperview()
            })

        }
    }
}

Add custom UIView at end of cell and remove it after animation is done.

• You can set custom view's frame as you want
• Add label(s) with background color and title as you want.

Here you should write code for not every time call this code in viewDidAppear it should be call once for only user indication.

回答2:

Transforming a cell to the left will not make the action button visible.

You need to send that cell into editing mode by calling the setEditing method on the cell, put this in your viewDidAppear:

let cell = posTblView.cellForRow(at: IndexPath(row: 0, section: 0))
cell.setEditing(true, animated: true)