X11: ポインタのグラブ

pointer_mode:  GrabModeAsync
keyboard_mode: GrabModeAsync
owner_events:  イベントマスクで OwnerGrabButtonMask が選択されている場合は True、それ以外は False
confine_to:    None
cursor:        None

#include <stdio.h>
#include <X11/Xlib.h>
#include <X11/keysym.h>

int main(int argc,char **argv)
{
    Display *disp;
    XSetWindowAttributes attr;
    Window win[2];
    XEvent ev;
    KeySym key;
    int i,fgrab = 0;
    
    disp = XOpenDisplay(NULL);
    if(!disp) return 1;

    //ウィンドウ作成

    for(i = 0; i < 2; i++)
    {
        attr.background_pixel = (i)? 0xffffff: 0;
        attr.event_mask = ButtonPressMask | ButtonReleaseMask
            | PointerMotionMask | ButtonMotionMask
            | EnterWindowMask | LeaveWindowMask | KeyPressMask;

        win[i] = XCreateWindow(disp, DefaultRootWindow(disp),
            i * 100, 0, 200, 200, 0,
            CopyFromParent, CopyFromParent, CopyFromParent,
            CWBackPixel | CWEventMask, &attr);

        XMapWindow(disp, win[i]);
    }

    //イベント

    while(1)
    {
        XNextEvent(disp, &ev);

        switch(ev.type)
        {
            case ButtonPress:
                printf("* [Press] x(%d) y(%d) button(%d)\n",
                    ev.xbutton.x, ev.xbutton.y, ev.xbutton.button);

                if(fgrab == 0 && ev.xbutton.button == Button1)
                {
                    XGrabPointer(disp, ev.xbutton.window, False,
                        ButtonPressMask | ButtonReleaseMask | EnterWindowMask | LeaveWindowMask
                        | PointerMotionMask | ButtonMotionMask,
                        GrabModeAsync, GrabModeAsync, None, None, CurrentTime);

                    fgrab = 1;
                    printf("# Grab - Button1\n");
                }

                fflush(stdout);
                break;
            case ButtonRelease:
                if(fgrab == 1 && ev.xbutton.button == Button1)
                {
                    XUngrabPointer(disp, CurrentTime);
                    fgrab = 0;

                    printf("# Ungrab - Button1\n");
                }
                break;
            case MotionNotify:
                printf("- [Motion] x(%d) y(%d)\n", ev.xmotion.x, ev.xmotion.y);
                fflush(stdout);
                break;
            case EnterNotify:
            case LeaveNotify:
                printf("$ [%s] <%s> x(%d) y(%d) mode(%d) detail(%d)\n",
                    (ev.type == EnterNotify)? "Enter": "Leave",
                    (ev.xcrossing.window == win[0])? "black": "white",
                    ev.xcrossing.x, ev.xcrossing.y,
                    ev.xcrossing.mode, ev.xcrossing.detail);
                fflush(stdout);
                break;

            case KeyPress:
                key = XLookupKeysym((XKeyEvent *)&ev, 0);
                if(key == XK_Return || key == XK_KP_Enter)
                    goto END;
                else if(key == ' ')
                {
                    if(fgrab == 2)
                    {
                        XUngrabPointer(disp, CurrentTime);
                        fgrab = 0;
                        printf("# Ungrab - key\n");
                    }
                    else if(fgrab == 0)
                    {
                        XGrabPointer(disp, ev.xkey.window, False,
                            ButtonPressMask | ButtonReleaseMask | EnterWindowMask | LeaveWindowMask
                            | PointerMotionMask | ButtonMotionMask,
                            GrabModeAsync, GrabModeAsync, None, None, CurrentTime);

                        fgrab = 2;
                        printf("# Grab - key\n");
                    }
                }
                break;
        }
    }

END:
    XCloseDisplay(disp);

    return 0;
}