背景

電商項目總喜歡在特定節(jié)日展示不同的icon圖標，但是為了修改圖標而更新版本的話，沒那個必要。
這里介紹一種不需要通過更新版本就可以動態(tài)修改APP圖標的方法。

??注意：該方法在iOS10.3及以上有效

實現(xiàn)

• 1 導(dǎo)入待替換的新圖片，放到項目工程新文件夾中；
• 2 配置 Info.plist 文件：

<key>CFBundleIcons</key>
<dict>
    <key>CFBundleAlternateIcons</key>
    <dict>
        <key>icon1</key>
        <dict>
            <key>CFBundleIconFiles</key>
            <array>
                <string>icon1</string>
            </array>
            <key>UIPrerenderedIcon</key>
            <false/>
        </dict>
        <key>icon2</key>
        <dict>
            <key>CFBundleIconFiles</key>
            <array>
                <string>icon2</string>
            </array>
            <key>UIPrerenderedIcon</key>
            <false/>
        </dict>
    </dict>
    <key>CFBundlePrimaryIcon</key>
    <dict>
        <key>CFBundleIconFiles</key>
    <array>
        <string>AppIcon60x60</string>
    </array>
    </dict>
</dict>

• 3 通過代碼替換

        if #available(iOS 10.3, *) {
            if UIApplication.shared.supportsAlternateIcons {
                print("you can change this app's icon")
            }else {
                print("you cannot change this app's icon")
                return
            }
            
            if let name = UIApplication.shared.alternateIconName {
                // CHANGE TO PRIMARY ICON  恢復(fù)默認 icon
                UIApplication.shared.setAlternateIconName(nil) { (err:Error?) in
                    print("set icon error：\(String(describing: err))")
                }
                print("the alternate icon's name is \(name)")
            }else {
                // CHANGE TO ALTERNATE ICON 指定icon圖標
                UIApplication.shared.setAlternateIconName("icon1") { (err:Error?) in
                    print("set icon error：\(String(describing: err))")
                }
            }
        }

• 4 去掉更換圖標時的彈框
  更換圖標時會出現(xiàn)系統(tǒng)彈框，可以使用Runtime來隱藏彈框，這樣方便在節(jié)日時候程序自動 無感 更改APP 的icon
  具體代碼如下：

extension UIViewController {

  //通過運行時替換系統(tǒng)的present方法

  public class func nkReplaceSystemPresent(){

    let systemSelector = #selector(UIViewController.present(_:animated:completion:))

    let nkSelector = #selector(UIViewController.newPesent(_:animated:completion:))



    let systemMethod = class_getInstanceMethod(self, systemSelector)

    let nkNewMethod = class_getInstanceMethod(self, nkSelector)
      method_exchangeImplementations(systemMethod!, nkNewMethod!)

  }



  @objc public func newPesent(_ vcToPresent:UIViewController, animated flag:Bool, completion: (() ->Void)? = nil) {

    if vcToPresent.isKind(of:UIAlertController.self) {

      let alertController = vcToPresent as? UIAlertController

      if alertController?.title==nil && alertController?.message==nil {
        return
      }
    }

    self.newPesent(vcToPresent, animated: flag)

  }

}
 

然后在滿足需求的控制器中調(diào)用即可。
方法如下:

    override func viewDidLoad() {
        super.viewDidLoad()
        DH_MyViewController.nkReplaceSystemPresent()
    }