Question

我正试图在swift中的播放按钮和暂停按钮之间切换。我在工具栏中有一个条形按钮项，其标识符最初设置为play。我试图搜索并发现以下code但它不起作用，当条形按钮在导航栏中时它看起来很有效

self.navigationItem.setLeftBarButtonItem(UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.Play, target: self, action: "TheMethodThatTheButtonShouldCall"), animated: true)

Answer 1

您需要在items上设置UIToolbar来更新工具栏项目：使用新项目调用func setItems(_items: [AnyObject]?,animated animated: Bool)以更新工具栏的商品

来源：https://developer.apple.com/library/prerelease/ios/documentation/UIKit/Reference/UIToolbar_Class/index.html#//apple_ref/occ/instm/UIToolbar/setItems:animated：

Answer 2

使用以下代码实现您的问题。适用于Swift 2.请注意我将IBAction插座连接到playBtn

import UIKit
import AVFoundation

class ViewController: UIViewController {

    @IBOutlet var sliderVal: UISlider!
    @IBOutlet var theToolbar: UIToolbar!

    var mySound = AVAudioPlayer()

    override func viewDidLoad() {
        super.viewDidLoad()

        let path = NSBundle.mainBundle().pathForResource("ColdPlay", ofType: "mp3")

        do {
        mySound = try AVAudioPlayer(contentsOfURL: NSURL(fileURLWithPath: path!))
        }
        catch{
            print("error caught")
        }
    }

   @IBAction func playBtn(sender: UIBarButtonItem) {

    let theBarbuttonItem = UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.Pause, target: self, action: "pauseBtn:")
    let arrayBarButtonItem = [theBarbuttonItem]
    theToolbar.setItems(arrayBarButtonItem, animated: true)


        mySound.play()
    }

    @IBAction func pauseBtn(sender: UIBarButtonItem) {
        let theBarbuttonItemB = UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.Play, target: self, action: "playBtn:")
        let arrayBarButtonItemB = [theBarbuttonItemB]
        theToolbar.setItems(arrayBarButtonItemB, animated: true)

        mySound.pause()
    }
}

如何更改swift工具栏中的条形按钮图标？

2 个答案: