user32.dll 中的 DragDetect (IntPtr, Point) 相当于单声道吗？

Question

有人知道上述 p/invoke 调用的托管代码以将其与 mono 一起使用吗？ 是否有 Linux 库提供与 Windows 上的 user32.dll 类似的功能？

Answer 1

我不确定 x11\GTK 的 DragDirect 调用是否有直接等效项，但您可以使用 Gdk.Pointer.Grab 和 Gdk.Pointer.Ungrab 获得相同的功能代码>方法。每当需要时捕获鼠标指针，然后跟踪鼠标移动，并在用户按 Esc 键或释放鼠标或鼠标超出拖动矩形时释放鼠标指针。

下面是一个小例子：

public partial class MainWindow : Gtk.Window
{
    public MainWindow () : base(Gtk.WindowType.Toplevel)
    {
        Build ();
    }

    protected void OnDeleteEvent (object sender, DeleteEventArgs a)
    {
        Application.Quit ();
        a.RetVal = true;
    }

    protected virtual void OnWidgetEvent (object o, Gtk.WidgetEventArgs args)
    {   
        if (args.Event is Gdk.EventMotion && args.Event.Type==Gdk.EventType.MotionNotify)
        {
            Gdk.EventMotion eventMotion = (Gdk.EventMotion)args.Event; 
            Console.WriteLine("mouse move {0} {1}", eventMotion.X, eventMotion.Y);
        }
        else if (args.Event is Gdk.EventKey && args.Event.Type==Gdk.EventType.KeyPress)
        {
            Gdk.EventKey eventKey = (Gdk.EventKey)args.Event;
            if (eventKey.Key==Gdk.Key.Escape)
            {
                Console.WriteLine("mouse pointer ungrab");
                Gtk.Grab.Remove(this);
                Gdk.Pointer.Ungrab(Gtk.Global.CurrentEventTime);
            }
        }
    }

    protected virtual void OnButton1WidgetEvent (object o, Gtk.WidgetEventArgs args)
    {
        if (args.Event is Gdk.EventButton && args.Event.Type==Gdk.EventType.ButtonPress)
        {
            Console.WriteLine("mouse pointer grab");
            Gdk.Pointer.Grab(this.GdkWindow, true,
                Gdk.EventMask.ButtonPressMask | Gdk.EventMask.ButtonReleaseMask | Gdk.EventMask.PointerMotionMask | Gdk.EventMask.EnterNotifyMask | Gdk.EventMask.LeaveNotifyMask, 
                null, null, Gtk.Global.CurrentEventTime); 
            Gtk.Grab.Add (this);
        }
    }
}

MainWindow UI 声明：

  <widget class="Gtk.Window" id="MainWindow" design-size="400 300">
    <property name="MemberName" />
    <property name="Title" translatable="yes">MainWindow</property>
    <property name="WindowPosition">CenterOnParent</property>
    <signal name="DeleteEvent" handler="OnDeleteEvent" />
    <signal name="WidgetEvent" handler="OnWidgetEvent" />
    <child>
      <widget class="Gtk.Fixed" id="fixed1">
        <property name="MemberName" />
        <property name="HasWindow">False</property>
        <child>
          <widget class="Gtk.Button" id="button1">
            <property name="MemberName" />
            <property name="CanFocus">True</property>
            <property name="Type">TextOnly</property>
            <property name="Label" translatable="yes">GtkButton</property>
            <property name="UseUnderline">True</property>
            <signal name="WidgetEvent" handler="OnButton1WidgetEvent" />
          </widget>
          <packing>
            <property name="X">165</property>
            <property name="Y">125</property>
          </packing>
        </child>
      </widget>
    </child>
  </widget>

有关 GTK 中鼠标指针处理的更多详细信息，请参见：鼠标指针

希望这有帮助，问候