QT global mouse listener

Question

I'm new to QT from Java. Is there something like this: https://code.google.com/p/jnativehook/ for QT? Can I get all the mouse events with coordinates? I've done the following:

bool MainWindow::eventFilter(QObject *obj, QEvent *event)
{
    if (event->type() == QEvent::MouseButtonRelease)
    {
      QMouseEvent *mouseEvent = static_cast<QMouseEvent*>(event);
      ui->listWidget->addItem(QString("Mouse pressed: %1,%2").arg(mouseEvent>pos().x()).arg(mouseEvent->pos().y()));
    }
  return false;
}

This works fine but it only does it inside my Application and not system wide. What can I do to get this working in QT? Also this only needs to run on windows...

[grabMouse](http://qt-project.org/doc/qt-5.0/qtwidgets/qwidget.html#grabMouse) on a (visible) widget should work — ratchet freak, Dec 05 '13 at 14:16
Just tried it with this: ui->listWidget->grabMouse(); But it just locked my window and didn't catch anything... — user754730, Dec 05 '13 at 14:19
[Hook for windows](http://msdn.microsoft.com/en-us/library/windows/desktop/ms644990(v=vs.85).aspx). — thuga, Dec 05 '13 at 14:28
Saw this website already but didn't know how to implement this. How can I call this? — user754730, Dec 05 '13 at 14:33
grabMouse() only helps if the mouse was pressed inside the application's window and then moved outside while hold pressed. — Frank Osterfeld, Dec 05 '13 at 22:46

score 5 · Accepted Answer · answered Dec 06 '13 at 13:30

It's actually very simple. I did not find ANY examples or anything.

I then found a video on YouTube which shows exactly what I'm searching for (For the keyboard but the mouse is basically the same).

So if ever someone needs this here you go:

#include <Windows.h>
#pragma comment(lib, "user32.lib")
HHOOK hHook = NULL;
using namespace std;

LRESULT CALLBACK MouseProc(int nCode, WPARAM wParam, LPARAM lParam) {   
    switch( wParam )
    {
      case WM_LBUTTONDOWN:  qDebug() << "Left click"; // Left click
    }
    return CallNextHookEx(hHook, nCode, wParam, lParam);
}

MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
hHook = SetWindowsHookEx(WH_MOUSE_LL, MouseProc, NULL, 0);
if (hHook == NULL) {
    qDebug() << "Hook failed";
}
ui->setupUi(this);
}

The following codes can be used inside the switch to detect which event was received:

WM_MOUSEMOVE = 0x200
WM_LBUTTONDOWN = 0x201
WM_LBUTTONUP = 0x202
WM_LBUTTONDBLCLK = 0x203
WM_RBUTTONDOWN = 0x204
WM_RBUTTONUP = 0x205
WM_RBUTTONDBLCLK = 0x206
WM_MBUTTONDOWN = 0x207
WM_MBUTTONUP = 0x208
WM_MBUTTONDBLCLK = 0x209
WM_MOUSEWHEEL = 0x20A
WM_XBUTTONDOWN = 0x20B
WM_XBUTTONUP = 0x20C
WM_XBUTTONDBLCLK = 0x20D
WM_MOUSEHWHEEL = 0x20E

You marked your own answer as "accepted", but the answer doesn't answer your own question. Your question was about a global mouse hook using Qt. Your answer was about a global mouse hook using Win32 (an entirely different technology). — Jamin Grey, Dec 18 '14 at 21:06
@JakeW Sorry forgot to add the link... https://www.youtube.com/watch?v=O0C4V6JmlNw There you go... — user754730, Aug 10 '15 at 12:49
This does work, but it makes the mouse cursor stutter when loading/deloading the application. Seems to much of a tradeoff to me. — i know nothing, Jan 04 '23 at 08:03

QT global mouse listener

1 Answers1