c# - UWP app .cs 文件从 xaml.cs 继承静态变量

Question

我已经创建了 PlayPage.xaml、PlayPage.xaml.cs 和 Game.cs 文件。PlayPage.xaml.cs 有两个变量，windowWidth 和 windowHeight。

我想从 Game.cs 访问两个公共(public)静态变量。

游戏.cs:

namespace UwpApp
{
    class Game
    {
        static Rectangle rectangle;
        PlayPage pg = new PlayPage();

        //Create a rectangle
        public Rectangle draw()
        {
            rectangle = new Rectangle();
            rectangle.Width = 70;
            rectangle.Height = 70;
            rectangle.Fill = new SolidColorBrush(Colors.Green);
            Canvas.SetLeft(rectangle, randPos());
            Canvas.SetTop(rectangle, randPos());
            return rectangle;
        }

        //Create a random X and Y position
        private Int32 randPos()
        {
            Random rnd = new Random();
            Debug.WriteLine(pg.windowWidth);
            return rnd.Next(0 , (int)pg.windowWidth);
        }
    }
}

PlayPage.xaml.cs:

namespace UwpApp
{
    /// <summary>
    /// An empty page that can be used on its own or navigated to within a Frame.
    /// </summary>
    public partial class PlayPage : Page
    {
        DispatcherTimer timer;
        Rectangle rect;
        bool isTapped;
        public static double windowWidth, windowHeight;

        Game game = new Game();

        public PlayPage()
        {
            this.InitializeComponent();

            startCounter.Visibility = Visibility.Collapsed;
            isTapped = false;
        }

        private void Load_Variable(object sender, RoutedEventArgs e)
        {
            windowWidth = canvas.ActualWidth;
            windowHeight = canvas.ActualHeight;
        }

        //Counter animation. (Number opacity, fall)
        private void counterAnimation()
        {
                startCounter.Visibility = Visibility.Visible;

                //Set Counter Horizontal Align
                double left = (canvas.ActualWidth - startCounter.ActualWidth) / 2;
                Canvas.SetLeft(startCounter, left);

                Storyboard storyboard = new Storyboard();

                DoubleAnimation opacityAnim = new DoubleAnimation();
                DoubleAnimation fallAnim = new DoubleAnimation();

                opacityAnim.From = 1;
                opacityAnim.To = 0;
                opacityAnim.Duration = new Duration(TimeSpan.FromSeconds(1));
                opacityAnim.AutoReverse = false;
                opacityAnim.RepeatBehavior = new RepeatBehavior(3);

                Storyboard.SetTarget(opacityAnim, this.startCounter);
                Storyboard.SetTargetProperty(opacityAnim, "(UIElement.Opacity)");

                fallAnim.From = -115;
                fallAnim.To = canvas.ActualHeight / 2;
                fallAnim.Duration = new Duration(TimeSpan.FromSeconds(1));
                fallAnim.AutoReverse = false;
                fallAnim.RepeatBehavior = new RepeatBehavior(3);

                Storyboard.SetTarget(fallAnim, this.startCounter);
                Storyboard.SetTargetProperty(fallAnim, "(Canvas.Top)");

                storyboard.Children.Add(opacityAnim);
                storyboard.Children.Add(fallAnim);

                storyboard.Begin();
        }

        //Countdown Timer
        private void countDown()
        {
            timer = new DispatcherTimer();
            timer.Tick += startCounter_CountDown;
            timer.Interval = new TimeSpan(0, 0, 1);
            timer.Start();
        }

        //Change Countdown value
        private void startCounter_CountDown(object sender, object e)
        {
            int counterNum = int.Parse(startCounter.Text);
            counterNum -= 1;
            startCounter.Text = counterNum.ToString();

            if (counterNum == 1)
            {
                timer.Stop();
                StartedGame();
            }
        }

        //Tap or Click to start the game
        private void TapToStart(object sender, TappedRoutedEventArgs e)
        {
            if(!isTapped)
            {
                isTapped = true;
                counterAnimation();
                countDown();
                this.TapToStartText.Visibility = Visibility.Collapsed;
            }
        }

        //Create rectangles
        private void StartedGame()
        {
            rect = game.draw();
            canvas.Children.Add(game.draw());
            Debug.WriteLine(windowWidth.ToString());
        }
    }
}

还有一件事:这一行我得到一个错误:PlayPage pg = new PlayPage(); Error (pic)

Answer 1

正如它所说，您图片中的错误是由于无限递归造成的。 Game 的构造函数实例化一个新的 PlayPage。 PlayPage 的构造函数实例化一个新游戏。它实例化了一个新的 PlayPage。实例化一个新游戏。等等。

静态成员通过类名访问，而不是通过实例访问。像这样:

PlayPage.windowWidth