Mouse position

Mouse position
You are encouraged to solve this task according to the task description, using any language you may know.

Get the current location of the mouse cursor relative to the active window. Please specify if the window may be externally created.

Ada

Library: GTK version GtkAda

Library: GtkAda

The GTK procedure is Get_Pointer. It returns mouse coordinates relatively to a window (internally created). The following program shows a button, which when pressed indicates coordinates of the mouse pointer relatively to the main window: <lang Ada> with GLib; use GLib; with Gtk.Button; use Gtk.Button; with Gtk.Label; use Gtk.Label; with Gtk.Window; use Gtk.Window; with Gtk.Widget; use Gtk.Widget; with Gtk.Table; use Gtk.Table;

with Gtk.Handlers; with Gtk.Main;

procedure Tell_Mouse is

  Window : Gtk_Window;
  Grid   : Gtk_Table;
  Button : Gtk_Button;
  Label  : Gtk_Label;

  package Handlers is new Gtk.Handlers.Callback (Gtk_Widget_Record);
  package Return_Handlers is
     new Gtk.Handlers.Return_Callback (Gtk_Widget_Record, Boolean);

  function Delete_Event (Widget : access Gtk_Widget_Record'Class)
     return Boolean is
  begin
     return False;
  end Delete_Event;

  procedure Destroy (Widget : access Gtk_Widget_Record'Class) is
  begin
     Gtk.Main.Main_Quit;
  end Destroy;

  procedure Clicked (Widget : access Gtk_Widget_Record'Class) is
     X, Y : GInt;
  begin
     Get_Pointer (Window, X, Y);
     Set_Text (Label, "At" & GInt'Image (X) & GInt'Image (Y));
  end Clicked;

begin

  Gtk.Main.Init;
  Gtk.Window.Gtk_New (Window);
  Gtk_New (Grid, 1, 2, False);
  Add (Window, Grid);
  Gtk_New (Label);
  Attach (Grid, Label, 0, 1, 0, 1);
  Gtk_New (Button, "Click me");
  Attach (Grid, Button, 0, 1, 1, 2);
  Return_Handlers.Connect
  (  Window,
     "delete_event",
     Return_Handlers.To_Marshaller (Delete_Event'Access)
  );
  Handlers.Connect
  (  Window,
     "destroy",
     Handlers.To_Marshaller (Destroy'Access)
  );
  Handlers.Connect
  (  Button,
     "clicked",
     Handlers.To_Marshaller (Clicked'Access)
  );
  Show_All (Grid);
  Show (Window);

  Gtk.Main.Main;

end Tell_Mouse; </lang>

AutoHotkey

Window may be externally created. <lang AutoHotkey> WinGetTitle, window, A MouseGetPos, x, y Msgbox, the mouse is at xpos %x% ypos %y% in window %window% </lang>

C

Library: Xlib

<lang c>#include <stdio.h>

1. include <X11/Xlib.h>

int main() {

 Display *d;
 Window inwin;      /* root window the pointer is in */
 Window inchildwin; /* child win the pointer is in */
 int rootx, rooty; /* relative to the "root" window; we are not interested in these,
                      but we can't pass NULL */
 int childx, childy;  /* the values we are interested in */
 Atom atom_type_prop; /* not interested */
 int actual_format;   /* should be 32 after the call */
 unsigned int mask;   /* status of the buttons */
 unsigned long n_items, bytes_after_ret;
 Window *props; /* since we are interested just in the first value, which is

a Window id */

 /* default DISPLAY */
 d = XOpenDisplay(NULL); 

 /* ask for active window (no error check); the client must be freedesktop
    compliant */
 (void)XGetWindowProperty(d, DefaultRootWindow(d),

XInternAtom(d, "_NET_ACTIVE_WINDOW", True), 0, 1, False, AnyPropertyType, &atom_type_prop, &actual_format, &n_items, &bytes_after_ret, (unsigned char**)&props);

 XQueryPointer(d, props[0], &inwin,  &inchildwin,

&rootx, &rooty, &childx, &childy, &mask);

 printf("relative to active window: %d,%d\n", childx, childy);

 XFree(props);           /* free mem */
 (void)XCloseDisplay(d); /* and close the display */
 return 0;

}</lang>

Java

Works with: Java version 1.5+

The mouse position can be checked at any time by calling <lang java5>Point mouseLocation = MouseInfo.getPointerInfo().getLocation();</lang> This returns a point on the entire screen, rather than relative to a particular window. This call can be combined with getLocation() from any Component (including a Frame, which is a window) to get the location relative to that Component.

Mathematica

<lang Mathematica> MousePosition["WindowAbsolute"] </lang>

OCaml

equivalent to the C example, uses the Xlib binding ocaml-xlib <lang OCaml>open Xlib

let () =

 let d = xOpenDisplay "" in

 (* ask for active window (no error check);
    the client must be freedesktop compliant *)
 let _, _, _, _, props =
   xGetWindowProperty_window d
       (xDefaultRootWindow d)
       (xInternAtom d "_NET_ACTIVE_WINDOW" true)
       0 1 false AnyPropertyType
 in

 let _, _, _, child, _ = xQueryPointer d props in
 begin match child with
 | Some(_, childx, childy) ->
     Printf.printf "relative to active window: %d,%d\n%!" childx childy;
 | None ->
     print_endline "the pointer is not on the same screen as the specified window"
 end;

 xCloseDisplay d;

</lang>

Tcl

Library: Tk

8.5

<lang tcl>set curWindow [lindex [wm stackorder .] end]

1. Everything below will work with anything from Tk 8.0 onwards

set x [expr {[winfo pointerx .] - [winfo rootx $curWindow]}] set y [expr {[winfo pointery .] - [winfo rooty $curWindow]}] tk_messageBox -message "the mouse is at ($x,$y) in window $curWindow"</lang>