c# - C#.NET Embedded Compact 2013-如何调用GetGestureInfo？

我必须开发一个C＃应用程序，该应用程序需要利用高级手势来改善用户体验。为此，我需要获取信息
当用户调用某个手势时。

因为WndProc是.NET CE中的忌讳，所以我使用OpenNETCE的Application2和IMessageFilter类接收WM流量。

在我的MessageFilter中，我寻找WM_GESTURE消息，这就是
我被卡住了。

通过调用此函数，我只是没有得到任何有意义的结果：

https://msdn.microsoft.com/en-us/library/ee503217.aspx

BOOL GetGestureInfo(
        HGESTUREINFO hGestureInfo
        PGESTUREINFO pGestureInfo
);

以下是相关代码：

public class TestMessageFilter : IMessageFilter
{
    [DllImport("coredll", SetLastError = true)]
    public static extern bool GetGestureInfo(IntPtr hGesture, ref GESTUREINFO lGesture);

    public static uint WM_GESTURE = 0x0119;

    public bool PreFilterMessage(ref Microsoft.WindowsCE.Forms.Message m)
    {
        // ...
        if (m.Msg == WM_GESTURE)
        {
            GESTUREINFO gi = new GESTUREINFO() {
                cbSize = (uint)Marshal.SizeOf(typeof(GESTUREINFO))
            };

            bool success = GetGestureInfo(m.LParam, ref gi);
            if (success)
            {
                // ...
            }
            else
            {
                int x = Marshal.GetLastWin32Error(); // => 87
            }
        }

        // ...
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct POINTS
    {
        public short x;
        public short y;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct GESTUREINFO
    {
        public UInt32 cbSize;
        public UInt32 dwFlags;
        public UInt32 dwID;
        public IntPtr hwndTarget;
        public POINTS ptsLocation;
        public UInt32 dwInstanceID;
        public UInt32 dwSequenceID;
        public UInt64 ullArguments;
        public UInt32 cbExtraArguments;
    }
}

它总是给我错误代码87。

ERROR_INVALID_PARAMETER

为什么不起作用？
什么无效
真让我发疯...

非常感谢。

编辑：
我发现这篇文章on the msdn forums使用IntPtr而不是
引用GestureInfo作为第二个参数。

[DllImport("coredll.dll")]
static extern int GetGestureInfo(IntPtr hGestureInfo, [In, Out] IntPtr pGestureInfo);
// ...
GESTUREINFO gi = new GESTUREINFO();
gi.cbSize = 48;

IntPtr outGI = Marshal.AllocHGlobal(48);
Marshal.StructureToPtr(gi, outGI, false);

bool bResult = (GetGestureInfo(lParam, outGI) == 1);
bool bHandled = false;
Marshal.FreeHGlobal(outGI);
Marshal.PtrToStructure(outGI, gi);
// ...

但这对我来说会导致相同的ERROR_INVALID_PARAMETER错误。

没有人有解决方案或其他方法来从C＃获取GestureInfo吗？

最佳答案

我只有Windows Embedded Compact 7的经验，但与2013年的差别应该不大-您是否首先启用手势？ （您可能是因为收到WM_GESTURE才这样做的，但无论如何这是代码）：

[DllImport(User32Library)]
public static extern bool EnableGestures(IntPtr hWnd, GestureMask flags, uint scope);

[Flags]
public enum GestureMask : ulong
{
    TGF_GID_PAN = 0x10,
    TGF_GID_SCROLL = 0x100,
    TGF_GID_HOLD = 0x200,
    TGF_GID_SELECT = 0x400,
    TGF_GID_DOUBLESELECT = 0x800,
    TGF_GID_DIRECTMANIPULATION = 0x1000,
    TGF_GID_ALL = TGF_GID_PAN | TGF_GID_SCROLL | TGF_GID_HOLD | TGF_GID_SELECT | TGF_GID_DOUBLESELECT,// | TGF_GID_DIRECTMANIPULATION,
}

我选择复制粘贴我们的工作示例；不记得是为了方便起见还是因为存在问题而将TGF_GID_DIRECTMANIPULATION排除在TGF_GID_ALL外

bool enabled = EnableGestures(Handle, Native.GestureMask.TGF_GID_ALL, 0);

GetGestureInfo的以下签名适用于我们的设备：

[DllImport("coredll.dll")]
public static extern bool GetGestureInfo(IntPtr hGestureInfo, ref GestureInfo pGestureInfo);

使用GestureInfo结构：

[StructLayout(LayoutKind.Sequential)]
public struct GestureInfo
{
    /// <summary>
    /// Specifies the size of the structure in bytes.  This must be set to Marshal.SizeOf(typeof(GESTUREINFO))
    /// </summary>
    public uint Size;
    /// <summary>
    /// Gesture Flags
    /// </summary>
    public GestureState State;
    /// <summary>
    /// Gesture Id
    /// </summary>
    public GestureKind Kind;
    /// <summary>
    /// HWND of the target winndow
    /// </summary>
    public IntPtr TargetWindow;
    /// <summary>
    /// Coordinates of start of gesture
    /// </summary>
    public short LocationX;
    /// <summary>
    /// Coordinates of start of gesture
    /// </summary>
    public short LocationY;
    /// <summary>
    /// Gesture Instance Id
    /// </summary>
    public uint InstanceId;
    /// <summary>
    /// Gesture Sequence Id
    /// </summary>
    public uint SequenceId;
    /// <summary>
    /// Arguments specific to gesture
    /// </summary>
    public ulong Arguments;
    /// <summary>
    /// Size of extra arguments in bytes
    /// </summary>
    public uint ExtraArguments;
}

手势状态：

[Flags]
public enum GestureState : uint
{
    /// <summary>
    /// The gesture has no associated state
    /// </summary>
    None = 0,
    /// <summary>
    /// The gesture is the beginning of pan gesture
    /// </summary>
    Begin = 1,
    /// <summary>
    /// The gesture is the end of a pan gesture that will transition into a scroll gesture
    /// </summary>
    Inertia = 2,
    /// <summary>
    /// The gesture is the end of a pan gesture
    /// </summary>
    End = 4
}

和GestureKind：

/// <summary>
/// The kind of gesture.
/// </summary>
public enum GestureKind : uint
{
    /// <summary>
    /// The beginning of a gesture operation.
    /// </summary>
    Begin = 1,
    /// <summary>
    /// The end of a gesture operation.
    /// </summary>
    End = 2,
    /// <summary>
    /// A pan gesture.
    /// </summary>
    Pan = 4,
    /// <summary>
    /// A scroll gesture.
    /// </summary>
    Scroll = 8,
    /// <summary>
    /// A hold gesture.
    /// </summary>
    Hold = 9,
    /// <summary>
    /// A select gesture.
    /// </summary>
    Select = 10,
    /// <summary>
    /// A double-select gesture.
    /// </summary>
    DoubleSelect = 11,
    /// <summary>
    /// Direct manipulation.
    /// </summary>
    DirectManipulation = 12,
}

调用该方法的代码：

GestureInfo gesture = new GestureInfo();
gesture.Size = (uint)Marshal.SizeOf(typeof(GestureInfo));
bool result = GetGestureInfo(lParam, ref gesture);

我认为这与您的第一次尝试没有太大区别。而在MSDN示例中唯一与众不同的是48的硬编码大小（可能意味着读取任何ExtraArguments）。

我们确实选择了设置自定义窗口过程-但是我不明白为什么这种区别很重要。