c# - MonoGame 中的跨平台文本框输入 (Windows/Ubuntu)

Question

我正在为使用 MonoGame 的桌面平台开发游戏。以前，它只针对 Windows 并使用纯 XNA。我正在探索使用 MonoGame 使其支持其他平台的选项，我当前的备用测试平台是 Ubuntu 15.04。

游戏的一项功能是支持与标准 Windows UI 文本框控件类似的文本框。为了实现这一点，我使用了 this StackOverflow answer 中的代码.

我的问题是:如何从链接的答案中编写可移植版本的功能，使其可以在备用桌面平台(在本例中为 Ubuntu)上运行？我正在寻找可以从 Windows 和 Ubuntu 上的游戏窗口捕获按键事件的东西。

附加信息:

链接的答案会覆盖 WndProc并通过触发事件(CharEntered、KeyDown、KeyUp)将输入传递到当前文本框。我已将答案的代码重构到可以将所有 Windows 功能封装在单个“事件”类中的程度:

internal class Win32KeyboardEvents : IKeyboardEvents
{
    public event CharEnteredHandler CharEntered;
    public event KeyEventHandler KeyDown;
    public event KeyEventHandler KeyUp;

    private readonly IntPtr _prevWndProc;
    private readonly NativeMethods.WndProc _hookProcDelegate;

    public Win32KeyboardEvents(GameWindow window)
    {
        _hookProcDelegate = HookProc;
        _prevWndProc = (IntPtr)NativeMethods.SetWindowLong(window.Handle, NativeMethods.GWL_WNDPROC,
            (int)Marshal.GetFunctionPointerForDelegate(_hookProcDelegate));
    }

    private IntPtr HookProc(IntPtr hWnd, uint msg, IntPtr wParam, IntPtr lParam)
    {
        IntPtr returnCode = NativeMethods.CallWindowProc(_prevWndProc, hWnd, msg, wParam, lParam);

        switch (msg)
        {
            case NativeMethods.WM_GETDLGCODE:
                returnCode = (IntPtr)(returnCode.ToInt32() | NativeMethods.DLGC_WANTALLKEYS);
                break;

            case NativeMethods.WM_KEYDOWN:
                if (KeyDown != null) //fire events that are subscribed to by textbox object based on which windows message is received
                    KeyDown(null, new XNAKeyEventArgs((Keys)wParam));
                break;

            case NativeMethods.WM_KEYUP:
                if (KeyUp != null)
                    KeyUp(null, new XNAKeyEventArgs((Keys)wParam));
                break;

            case NativeMethods.WM_CHAR:
                if (CharEntered != null)
                    CharEntered(null, new Win32CharEnteredEventArgs((char)wParam, lParam.ToInt32()));
                break;
        }

        return returnCode;
    }
}

我第一次尝试在 Ubuntu 上运行的东西是创建一个 GameComponent -派生对象在组件的Update() 中监听键盘输入并适本地触发事件，但这很快就变得太复杂了。

我已经使用 GTK# 进行了调查，但有很多依赖项我不想安装，除非 GTK# 是最好的方法。这是我的 GTK# 尝试，由于缺少依赖关系，目前未经测试:

internal class CrossPlatformKeyboardEvents : DrawingArea, IKeyboardEvents
{
    public event CharEnteredHandler CharEntered = delegate { };
    public event KeyEventHandler KeyDown = delegate { };
    public event KeyEventHandler KeyUp = delegate { };

    public CrossPlatformKeyboardEvents()
    {
        Application.Init();
        Application.Run();

        AddEvents((int)EventMask.KeyPressMask);
        AddEvents((int)EventMask.KeyReleaseMask);
    }

    [ConnectBefore]
    protected override bool OnKeyPressEvent(EventKey evnt)
    {
        if (IsPastEvent(evnt))
        {
            CharEntered(null, new CharEnteredEventArgs(KeyboardDispatcher.CHAR_PASTE_CODE));
            return base.OnKeyPressEvent(evnt);
        }

        switch (evnt.Key)
        {
            case Key.Return:
                CharEntered(null, new CharEnteredEventArgs(KeyboardDispatcher.CHAR_RETURNKEY_CODE));
                break;
            case Key.BackSpace:
                CharEntered(null, new CharEnteredEventArgs(KeyboardDispatcher.CHAR_BACKSPACE_CODE));
                break;
            case Key.Tab:
                CharEntered(null, new CharEnteredEventArgs(KeyboardDispatcher.CHAR_TAB_CODE));
                break;
        }

        var keyCode = GetXNAKey(evnt.Key);
        if (keyCode != Keys.None)
            KeyDown(null, new XNAKeyEventArgs(keyCode));

        return base.OnKeyPressEvent(evnt);
    }

    [ConnectBefore]
    protected override bool OnKeyReleaseEvent(EventKey evnt)
    {
        var keyCode = GetXNAKey(evnt.Key);
        if (keyCode != Keys.None)
            KeyUp(null, new XNAKeyEventArgs(keyCode));
        return base.OnKeyReleaseEvent(evnt);
    }

    private bool IsPastEvent(EventKey evnt)
    {
        return (evnt.State & ModifierType.ControlMask) > 0 && (evnt.Key == Key.V || evnt.Key == Key.v);
    }

    private Keys GetXNAKey(Key key)
    {
        if ((key >= Key.Key_0 && key <= Key.Key_9) ||
            (key >= Key.A && key <= Key.Z))
        {
            return (Keys) key;
        }
        if (key >= Key.a && key <= Key.z)
        {
            return (Keys) (key - 32);
        }

        return Keys.None;
        //switch (key)
        //{

        //}
    }

Answer 1

我通过使用 TextInput event on GameWindow 解决了这个问题在 MonoGame 中。

这是一个扩展，它是 MonoGame 的一部分，但不是 Xna 的一部分。目前，我有 2 个项目 - 一个用于标准 Xna，一个用于 Monogame。 Monogame 项目具有指向我的 Xna 项目中所有文件的链接，因此它们共享相同的代码。

由于我的项目的设置方式，我还必须添加一个编译器标志 (MONO)，该标志将该代码排除在为标准 XNA 编译之外。

完整类(class)(替换问题中发布的 CrossPlatformKeyboardEvents):

internal sealed class MonoGameKeyboardEvents : IKeyboardEvents
{
    public event CharEnteredHandler CharEntered;

    private readonly GameWindow _window;

    public MonoGameKeyboardEvents(GameWindow window)
    {
        _window = window;
#if !MONO
        if (CharEntered != null) //hide warning for "member is not used"
            CharEntered(null, null);
#else
        _window.TextInput += GameWindow_TextInput;
#endif
    }

#if MONO
    private void GameWindow_TextInput(object sender, TextInputEventArgs e)
    {
        if (CharEntered != null)
        {
            CharEntered(null, new CharEnteredEventArgs(e.Character));
        }
    }

    ~MonoGameKeyboardEvents()
    {
        Dispose(false);
    }
#endif

    public void Dispose()
    {
#if !MONO
    }
#else
        Dispose(true);
    }

    private void Dispose(bool disposing)
    {
        if (!disposing) return;

        _window.TextInput -= GameWindow_TextInput;
    }
#endif
}