ios13更改状态栏颜色

iOS 13之后，苹果禁止KVC直接修改私有属性。以前用KVC修改状态栏背景色也会Crash。
新的解决办法如下。

if (@available(iOS 13.0, *)) {
       UIView *statusBar = [[UIView alloc]initWithFrame:[UIApplication sharedApplication].keyWindow.windowScene.statusBarManager.statusBarFrame] ;
        statusBar.backgroundColor = color;
        [[UIApplication sharedApplication].keyWindow addSubview:statusBar];
    } else {
        // Fallback on earlier versions
        UIView *statusBar = [[[UIApplication sharedApplication] valueForKey:@"statusBarWindow"] valueForKey:@"statusBar"];
           if ([statusBar respondsToSelector:@selector(setBackgroundColor:)]) {
               statusBar.backgroundColor = color;
           }
    }

swift

     if #available(iOS 13.0, *) {
        let statusBar : UIView = UIView.init(frame: UIApplication.shared.keyWindow?.windowScene?.statusBarManager?.statusBarFrame ?? CGRect.init(x: 0, y: 0, width: kScreenW, height: 20))
        statusBar.backgroundColor = color
        UIApplication.shared.keyWindow?.addSubview(statusBar)
        
        } else {
            // Fallback on earlier versions
            let statusBarWindow : UIView = UIApplication.shared.value(forKey: "statusBarWindow") as! UIView
            let statusBar : UIView = statusBarWindow.value(forKey: "statusBar") as! UIView
            if statusBar.responds(to:#selector(setter: UIView.backgroundColor)) {
                        statusBar.backgroundColor = color
            }
        }