我想在我的图书馆中播放25首歌曲.这是我的代码:
var allSongsArray: [MPMediaItem] = []
let songsQuery = MPMediaQuery.songsQuery()
func numberOfSectionsInTableView(tableView: UITableView) -> Int {
return 1
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return 25 //allSongsArray.count
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("cell")
let items = allSongsArray[indexPath.row]
cell?.textLabel?.text = items.title
cell?.detailTextLabel?.text = items.artist
cell?.imageView?.image = items.artwork?.imageWithSize(imageSize)
return cell!
}
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当我运行它时,它会崩溃,因为:
致命错误:索引超出范围
我试图更改numberOfRowsInSection为allSongsArray.count,但最终会出现相同的错误.
我创建了一个只有一个按钮,一个文本字段和一个标签的Xcode项目。当文本字段输入为“ test123”或按钮被按下时,我只想使标签可见。带按钮的部分效果很好,但是无论我在文本字段中键入什么内容,标签都保持隐藏状态。有人帮忙吗?这是我当前的代码:
import UIKit
class ViewController: UIViewController, UITextFieldDelegate {
@IBOutlet weak var Label: UILabel!
@IBOutlet weak var Examplefield: UITextField!
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
Label.hidden = true
Examplefield.resignFirstResponder()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
@IBAction func ButtonPressed(sender: UIButton) {
Label.hidden = false
}
func textFieldDidEndEditing(textField: UITextField) {
if Examplefield.text == "test123" {
Label.hidden = false
}
else …Run Code Online (Sandbox Code Playgroud)