ios - 如何在 CGRectMake 函数中使用变量 - 尝试以表格结构输出数据

Question

我试图通过实用地创建和堆叠标签来输出一个帐户的“ friend ”列表。我已经从 MySQL 数据库(可通过与 PHP 脚本交互的 NSURL 访问)中获取帐户的 friend 并将它们加载到一个数组中。目标是遍历数组并创建一个标签，每次迭代时该标签的位置略低于前一个标签。我遇到的问题是，当我将一个变量传递给 CGRectMake 函数来创建标签时，它不会接受 int，因为它不是“CGFloat”类型。我觉得我几乎尝试了所有方法，但我永远无法正确转换数据类型。
这是我的代码:

import UIKit

class viewFriendsViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        let friendsArray = ["billy", "joe", "bob", "jim"]
        var inc = 0
        for index in friendsArray {
            let label: UILabel = UILabel()
            let yPos: CGFloat = Float(inc * 10)
            label.frame = CGRectMake(50, 50, 200, yPos)
            label.backgroundColor = UIColor.blackColor()
            label.textColor = UIColor.whiteColor()
            label.textAlignment = NSTextAlignment.Center
            label.text = "\(index)"
            self.view.addSubview(label)
            inc = inc + 1 // I have not been able to play with the label yet to determine how to move it's vertical position because I cannot run the program due to the casting error.
        }
    }
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()

    }

}

Answer 1

试试这个

var inc = 0
    for index in friendsArray {
        let label: UILabel = UILabel()

        //type conversion is 
        let yPos = CGFloat(inc * 10)

        label.frame = CGRectMake(50,yPos,200,50)  // if you want to change the Y-Coodinates use in Y frame not in height
        label.backgroundColor = UIColor.blackColor()
        label.textColor = UIColor.whiteColor()
        label.textAlignment = NSTextAlignment.Center
        label.text = "\(index)"
        self.view.addSubview(label)
        inc = inc + 1 
    }

上面的选择不行试试这个

  var inc : CGFloat = 0
    for index in friendsArray {
        let label: UILabel = UILabel()

        label.frame = CGRectMake(50,inc,200,50)  // if you want to change the Y-Coodinates use in Y frame not in height
        label.backgroundColor = UIColor.blackColor()
        label.textColor = UIColor.whiteColor()
        label.textAlignment = NSTextAlignment.Center
        label.text = "\(index)"
        self.view.addSubview(label)
        inc = inc * 10  //  inc + 10
    }