QT 在Windows上实现全局快捷键(全局热键)

2022年6月2日 9714点热度 5人点赞 2条评论

前言

Qt 提供了QShortcut来实现快捷键的功能,不过它的响应范围只局限于窗口内。如果脱离了进程窗口,如在桌面,或者正在使用其他软件,是无法响应的。

要解决这样的问题可以使用Windows 提供的API再结合qt的一些功能来实现一个全局可响应的快捷键。

需要用到的技术

RegisterHotKey()

这是是一个winAPI函数,它的作用是像系统注册一个快捷键,注册成功后系统会根据全局的键盘输入来判断快捷键是否被触发,触发之后通过WinMessage的方式来通知注册者。

BOOL WINAPI RegisterHotKey(
HWND hWnd,
int id,
UINT fsModifiers,
UINT vk
);
BOOL WINAPI RegisterHotKey( HWND hWnd, int id, UINT fsModifiers, UINT vk );
BOOL WINAPI RegisterHotKey( 
 HWND hWnd,
 int id,
 UINT fsModifiers,
 UINT vk
);

这是它的函数原型

参数介绍

hWnd:接收热键产生WM_HOTKEY消息的窗口句柄。若该参数NULL,传递给调用线程的WM_HOTKEY消息必须在消息循环中进行处理。

id:定义热键的标识符。调用线程中的其他热键,不能使用同样的标识符。应用程序必须定义一个0X0000-0xBFFF范围的值。一个共享的动态链接库(DLL)必须定义一个范围为0xC000-0xFFFF的值(GlobalAddAtomA函数返回该范围)。为了避免与其他动态链接库定义的热键冲突,一个DLL必须使用GlobalAddAtomA函数获得热键的标识符。

fsModifoers:定义为了产生WM_HOTKEY消息而必须与由nVirtKey参数定义的键一起按下的键。

该参数可以是如下值的组合:

含意
MOD_ALT 0x0001 按下的可以是任一Alt键。
MOD_SHIFT 0x0004 按下的可以是任一Shift键。
MOD_WIN 0x0008 按下的可以是任一Windows徽标键。
MOD_NOREPEAT 0x4000 更改热键行为,以便键盘自动重复不会产生多个热键通知。
MOD_CONTROL 0x0002 按下的可以是任一Ctrl键。

vk: 定义热键的虚拟键码。

QT事件机制处理windows原生事件

QApplication::installNativeEventFilter() 是QT提供的一种事件机制,可以通过这个函数安装一个过滤器来处理Windows原生的事件,这个可以参考之前的博客 QT事件机制的简单使用

使用时,需要继承QAbstractNativeEventFilter类,实现它的纯虚函数:

virtual bool nativeEventFilter(const QByteArray &eventType, void *message, long *result) = 0
virtual bool nativeEventFilter(const QByteArray &eventType, void *message, long *result) = 0
virtual bool    nativeEventFilter(const QByteArray &eventType, void *message, long *result) = 0

在这个函数里处理Windows原生的事件消息。

message指针可以强制转换为WinApi中的Msg类型,然后按照Msg中的信息处理即可。

最后调用QApplication::installNativeEventFilter() 传入类对象指针即可。

实现步骤

  1. 调用RegisterHotKey()注册一个系统级的快捷键
  2. 实现一个事件过滤器
  3. 将之间过滤器安装到QApplication

具体代码

.h

#pragma once
#include <QAbstractNativeEventFilter>
class NativeEventFilter :public QAbstractNativeEventFilter {
public:
NativeEventFilter(const unsigned int& mod, const unsigned int& key);
public:
bool nativeEventFilter(const QByteArray& eventType, void* message, long* result);
unsigned int mod, key;
};
class ShortcutTest{
public:
ShortcutTest() {};
~ShortcutTest() {};
public:
void registerShortcut(const NativeEventFilter &filter);
};
#pragma once #include <QAbstractNativeEventFilter> class NativeEventFilter :public QAbstractNativeEventFilter { public: NativeEventFilter(const unsigned int& mod, const unsigned int& key); public: bool nativeEventFilter(const QByteArray& eventType, void* message, long* result); unsigned int mod, key; }; class ShortcutTest{ public: ShortcutTest() {}; ~ShortcutTest() {}; public: void registerShortcut(const NativeEventFilter &filter); };
#pragma once
#include <QAbstractNativeEventFilter>

class NativeEventFilter :public QAbstractNativeEventFilter {
public:
    NativeEventFilter(const unsigned int& mod, const unsigned int& key);
public:
    bool nativeEventFilter(const QByteArray& eventType, void* message, long* result);
    unsigned int mod, key;
};

class ShortcutTest{
public:
    ShortcutTest() {};
    ~ShortcutTest() {};
public:
    void registerShortcut(const NativeEventFilter &filter);

};

.cpp

#include "ShortcutTest.h"
#include <windows.h>
#include <iostream>
NativeEventFilter::NativeEventFilter(const unsigned int& mod, const unsigned int& key)
{
this->mod = mod;
this->key = key;
}
bool NativeEventFilter::nativeEventFilter(const QByteArray& eventType, void* message, long* result)
{
MSG* msg = static_cast<MSG*>(message);
if (msg->message == WM_HOTKEY)
{
const quint32 keycode = HIWORD(msg->lParam);
const quint32 modifiers = LOWORD(msg->lParam);
if (keycode == key && mod == modifiers)
std::cerr << "shortcut trigger!" << std::endl;
}
return false;
}
void ShortcutTest::registerShortcut(const NativeEventFilter& filter)
{
int id = filter.key ^ filter.mod;
BOOL ok = RegisterHotKey(0, id, filter.mod, filter.key);
if (!ok)
std::cerr << "register shortcut failed!" << std::endl;
}
#include "ShortcutTest.h" #include <windows.h> #include <iostream> NativeEventFilter::NativeEventFilter(const unsigned int& mod, const unsigned int& key) { this->mod = mod; this->key = key; } bool NativeEventFilter::nativeEventFilter(const QByteArray& eventType, void* message, long* result) { MSG* msg = static_cast<MSG*>(message); if (msg->message == WM_HOTKEY) { const quint32 keycode = HIWORD(msg->lParam); const quint32 modifiers = LOWORD(msg->lParam); if (keycode == key && mod == modifiers) std::cerr << "shortcut trigger!" << std::endl; } return false; } void ShortcutTest::registerShortcut(const NativeEventFilter& filter) { int id = filter.key ^ filter.mod; BOOL ok = RegisterHotKey(0, id, filter.mod, filter.key); if (!ok) std::cerr << "register shortcut failed!" << std::endl; }
#include "ShortcutTest.h"
#include <windows.h>
#include <iostream>

NativeEventFilter::NativeEventFilter(const unsigned int& mod, const unsigned int& key)
{
    this->mod = mod;
    this->key = key;
}

bool NativeEventFilter::nativeEventFilter(const QByteArray& eventType, void* message, long* result)
{
    MSG* msg = static_cast<MSG*>(message);
    if (msg->message == WM_HOTKEY)
    {
        const quint32 keycode = HIWORD(msg->lParam);
        const quint32 modifiers = LOWORD(msg->lParam);

        if (keycode == key && mod == modifiers)
            std::cerr << "shortcut trigger!" << std::endl;
    }

    return false;
}

void ShortcutTest::registerShortcut(const NativeEventFilter& filter)
{
    int id = filter.key ^ filter.mod;
    BOOL ok = RegisterHotKey(0, id, filter.mod, filter.key);
    if (!ok)
        std::cerr << "register shortcut failed!" << std::endl;
}

main()

int main(int argc, char *argv[])
{
QApplication a(argc, argv);
NativeEventFilter filter(MOD_ALT,'W');
a.installNativeEventFilter(&filter);
ShortcutTest test;
test.registerShortcut(filter);
return a.exec();
}
int main(int argc, char *argv[]) { QApplication a(argc, argv); NativeEventFilter filter(MOD_ALT,'W'); a.installNativeEventFilter(&filter); ShortcutTest test; test.registerShortcut(filter); return a.exec(); }
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    NativeEventFilter filter(MOD_ALT,'W');
    a.installNativeEventFilter(&filter);
    ShortcutTest test;
    test.registerShortcut(filter);

    return a.exec();
}

运行结果:

image-20220602133928254

补充

在代码中传虚拟按键代码时,传了一个char ‘w’ 过去,最开始我是以为字母区的虚拟码应该是VK_xx这样的格式,尝试了以下并不是。然后就尝试到头文件中去找,找到了这样一段注释:

/*
* VK_0 - VK_9 are the same as ASCII '0' - '9' (0x30 - 0x39)
* 0x40 : unassigned
* VK_A - VK_Z are the same as ASCII 'A' - 'Z' (0x41 - 0x5A)
*/
/* * VK_0 - VK_9 are the same as ASCII '0' - '9' (0x30 - 0x39) * 0x40 : unassigned * VK_A - VK_Z are the same as ASCII 'A' - 'Z' (0x41 - 0x5A) */
/*
 * VK_0 - VK_9 are the same as ASCII '0' - '9' (0x30 - 0x39)
 * 0x40 : unassigned
 * VK_A - VK_Z are the same as ASCII 'A' - 'Z' (0x41 - 0x5A)
 */

因为数字键和字母键的键码和他们的ASCII码是一样的,所以在头文件中没有定义。

注意:这里的字母要使用大写的,小写的不行

Qt::key 转换为WinAPi的虚拟键码的互相转换

QT 中提供QKeySequenceEdit 给用户输入快捷键,得到是结果是Qt::key类型的,想要使用WinAPI注册快捷键还需要一些转换,这里提供以下转换函数,否则又是一个体力活。

unsigned int nativeModifiers(Qt::KeyboardModifiers modifiers)
{
quint32 native = 0;
if (modifiers & Qt::ShiftModifier)
native |= MOD_SHIFT;
if (modifiers & Qt::ControlModifier)
native |= MOD_CONTROL;
if (modifiers & Qt::AltModifier)
native |= MOD_ALT;
if (modifiers & Qt::MetaModifier)
native |= MOD_WIN;
return native;
}
unsigned int nativeKeycode(Qt::Key key)
{
switch (key)
{
case Qt::Key_Escape:
return VK_ESCAPE;
case Qt::Key_Tab:
case Qt::Key_Backtab:
return VK_TAB;
case Qt::Key_Backspace:
return VK_BACK;
case Qt::Key_Return:
case Qt::Key_Enter:
return VK_RETURN;
case Qt::Key_Insert:
return VK_INSERT;
case Qt::Key_Delete:
return VK_DELETE;
case Qt::Key_Pause:
return VK_PAUSE;
case Qt::Key_Print:
return VK_PRINT;
case Qt::Key_Clear:
return VK_CLEAR;
case Qt::Key_Home:
return VK_HOME;
case Qt::Key_End:
return VK_END;
case Qt::Key_Left:
return VK_LEFT;
case Qt::Key_Up:
return VK_UP;
case Qt::Key_Right:
return VK_RIGHT;
case Qt::Key_Down:
return VK_DOWN;
case Qt::Key_PageUp:
return VK_PRIOR;
case Qt::Key_PageDown:
return VK_NEXT;
case Qt::Key_F1:
return VK_F1;
case Qt::Key_F2:
return VK_F2;
case Qt::Key_F3:
return VK_F3;
case Qt::Key_F4:
return VK_F4;
case Qt::Key_F5:
return VK_F5;
case Qt::Key_F6:
return VK_F6;
case Qt::Key_F7:
return VK_F7;
case Qt::Key_F8:
return VK_F8;
case Qt::Key_F9:
return VK_F9;
case Qt::Key_F10:
return VK_F10;
case Qt::Key_F11:
return VK_F11;
case Qt::Key_F12:
return VK_F12;
case Qt::Key_F13:
return VK_F13;
case Qt::Key_F14:
return VK_F14;
case Qt::Key_F15:
return VK_F15;
case Qt::Key_F16:
return VK_F16;
case Qt::Key_F17:
return VK_F17;
case Qt::Key_F18:
return VK_F18;
case Qt::Key_F19:
return VK_F19;
case Qt::Key_F20:
return VK_F20;
case Qt::Key_F21:
return VK_F21;
case Qt::Key_F22:
return VK_F22;
case Qt::Key_F23:
return VK_F23;
case Qt::Key_F24:
return VK_F24;
case Qt::Key_Space:
return VK_SPACE;
case Qt::Key_Asterisk:
return VK_MULTIPLY;
case Qt::Key_Plus:
return VK_ADD;
case Qt::Key_Comma:
return VK_SEPARATOR;
case Qt::Key_Minus:
return VK_SUBTRACT;
case Qt::Key_Slash:
return VK_DIVIDE;
case Qt::Key_MediaNext:
return VK_MEDIA_NEXT_TRACK;
case Qt::Key_MediaPrevious:
return VK_MEDIA_PREV_TRACK;
case Qt::Key_MediaPlay:
return VK_MEDIA_PLAY_PAUSE;
case Qt::Key_MediaStop:
return VK_MEDIA_STOP;
case Qt::Key_VolumeDown:
return VK_VOLUME_DOWN;
case Qt::Key_VolumeUp:
return VK_VOLUME_UP;
case Qt::Key_VolumeMute:
return VK_VOLUME_MUTE;
case Qt::Key_0:
case Qt::Key_1:
case Qt::Key_2:
case Qt::Key_3:
case Qt::Key_4:
case Qt::Key_5:
case Qt::Key_6:
case Qt::Key_7:
case Qt::Key_8:
case Qt::Key_9:
return key;
case Qt::Key_A:
case Qt::Key_B:
case Qt::Key_C:
case Qt::Key_D:
case Qt::Key_E:
case Qt::Key_F:
case Qt::Key_G:
case Qt::Key_H:
case Qt::Key_I:
case Qt::Key_J:
case Qt::Key_K:
case Qt::Key_L:
case Qt::Key_M:
case Qt::Key_N:
case Qt::Key_O:
case Qt::Key_P:
case Qt::Key_Q:
case Qt::Key_R:
case Qt::Key_S:
case Qt::Key_T:
case Qt::Key_U:
case Qt::Key_V:
case Qt::Key_W:
case Qt::Key_X:
case Qt::Key_Y:
case Qt::Key_Z:
return key;
default:
return 0;
}
}
unsigned int nativeModifiers(Qt::KeyboardModifiers modifiers) { quint32 native = 0; if (modifiers & Qt::ShiftModifier) native |= MOD_SHIFT; if (modifiers & Qt::ControlModifier) native |= MOD_CONTROL; if (modifiers & Qt::AltModifier) native |= MOD_ALT; if (modifiers & Qt::MetaModifier) native |= MOD_WIN; return native; } unsigned int nativeKeycode(Qt::Key key) { switch (key) { case Qt::Key_Escape: return VK_ESCAPE; case Qt::Key_Tab: case Qt::Key_Backtab: return VK_TAB; case Qt::Key_Backspace: return VK_BACK; case Qt::Key_Return: case Qt::Key_Enter: return VK_RETURN; case Qt::Key_Insert: return VK_INSERT; case Qt::Key_Delete: return VK_DELETE; case Qt::Key_Pause: return VK_PAUSE; case Qt::Key_Print: return VK_PRINT; case Qt::Key_Clear: return VK_CLEAR; case Qt::Key_Home: return VK_HOME; case Qt::Key_End: return VK_END; case Qt::Key_Left: return VK_LEFT; case Qt::Key_Up: return VK_UP; case Qt::Key_Right: return VK_RIGHT; case Qt::Key_Down: return VK_DOWN; case Qt::Key_PageUp: return VK_PRIOR; case Qt::Key_PageDown: return VK_NEXT; case Qt::Key_F1: return VK_F1; case Qt::Key_F2: return VK_F2; case Qt::Key_F3: return VK_F3; case Qt::Key_F4: return VK_F4; case Qt::Key_F5: return VK_F5; case Qt::Key_F6: return VK_F6; case Qt::Key_F7: return VK_F7; case Qt::Key_F8: return VK_F8; case Qt::Key_F9: return VK_F9; case Qt::Key_F10: return VK_F10; case Qt::Key_F11: return VK_F11; case Qt::Key_F12: return VK_F12; case Qt::Key_F13: return VK_F13; case Qt::Key_F14: return VK_F14; case Qt::Key_F15: return VK_F15; case Qt::Key_F16: return VK_F16; case Qt::Key_F17: return VK_F17; case Qt::Key_F18: return VK_F18; case Qt::Key_F19: return VK_F19; case Qt::Key_F20: return VK_F20; case Qt::Key_F21: return VK_F21; case Qt::Key_F22: return VK_F22; case Qt::Key_F23: return VK_F23; case Qt::Key_F24: return VK_F24; case Qt::Key_Space: return VK_SPACE; case Qt::Key_Asterisk: return VK_MULTIPLY; case Qt::Key_Plus: return VK_ADD; case Qt::Key_Comma: return VK_SEPARATOR; case Qt::Key_Minus: return VK_SUBTRACT; case Qt::Key_Slash: return VK_DIVIDE; case Qt::Key_MediaNext: return VK_MEDIA_NEXT_TRACK; case Qt::Key_MediaPrevious: return VK_MEDIA_PREV_TRACK; case Qt::Key_MediaPlay: return VK_MEDIA_PLAY_PAUSE; case Qt::Key_MediaStop: return VK_MEDIA_STOP; case Qt::Key_VolumeDown: return VK_VOLUME_DOWN; case Qt::Key_VolumeUp: return VK_VOLUME_UP; case Qt::Key_VolumeMute: return VK_VOLUME_MUTE; case Qt::Key_0: case Qt::Key_1: case Qt::Key_2: case Qt::Key_3: case Qt::Key_4: case Qt::Key_5: case Qt::Key_6: case Qt::Key_7: case Qt::Key_8: case Qt::Key_9: return key; case Qt::Key_A: case Qt::Key_B: case Qt::Key_C: case Qt::Key_D: case Qt::Key_E: case Qt::Key_F: case Qt::Key_G: case Qt::Key_H: case Qt::Key_I: case Qt::Key_J: case Qt::Key_K: case Qt::Key_L: case Qt::Key_M: case Qt::Key_N: case Qt::Key_O: case Qt::Key_P: case Qt::Key_Q: case Qt::Key_R: case Qt::Key_S: case Qt::Key_T: case Qt::Key_U: case Qt::Key_V: case Qt::Key_W: case Qt::Key_X: case Qt::Key_Y: case Qt::Key_Z: return key; default: return 0; } }
unsigned int nativeModifiers(Qt::KeyboardModifiers modifiers)
{
    quint32 native = 0;
    if (modifiers & Qt::ShiftModifier)
        native |= MOD_SHIFT;
    if (modifiers & Qt::ControlModifier)
        native |= MOD_CONTROL;
    if (modifiers & Qt::AltModifier)
        native |= MOD_ALT;
    if (modifiers & Qt::MetaModifier)
        native |= MOD_WIN;
    return native;
}

unsigned int nativeKeycode(Qt::Key key)
{
    switch (key)
    {
    case Qt::Key_Escape:
        return VK_ESCAPE;
    case Qt::Key_Tab:
    case Qt::Key_Backtab:
        return VK_TAB;
    case Qt::Key_Backspace:
        return VK_BACK;
    case Qt::Key_Return:
    case Qt::Key_Enter:
        return VK_RETURN;
    case Qt::Key_Insert:
        return VK_INSERT;
    case Qt::Key_Delete:
        return VK_DELETE;
    case Qt::Key_Pause:
        return VK_PAUSE;
    case Qt::Key_Print:
        return VK_PRINT;
    case Qt::Key_Clear:
        return VK_CLEAR;
    case Qt::Key_Home:
        return VK_HOME;
    case Qt::Key_End:
        return VK_END;
    case Qt::Key_Left:
        return VK_LEFT;
    case Qt::Key_Up:
        return VK_UP;
    case Qt::Key_Right:
        return VK_RIGHT;
    case Qt::Key_Down:
        return VK_DOWN;
    case Qt::Key_PageUp:
        return VK_PRIOR;
    case Qt::Key_PageDown:
        return VK_NEXT;
    case Qt::Key_F1:
        return VK_F1;
    case Qt::Key_F2:
        return VK_F2;
    case Qt::Key_F3:
        return VK_F3;
    case Qt::Key_F4:
        return VK_F4;
    case Qt::Key_F5:
        return VK_F5;
    case Qt::Key_F6:
        return VK_F6;
    case Qt::Key_F7:
        return VK_F7;
    case Qt::Key_F8:
        return VK_F8;
    case Qt::Key_F9:
        return VK_F9;
    case Qt::Key_F10:
        return VK_F10;
    case Qt::Key_F11:
        return VK_F11;
    case Qt::Key_F12:
        return VK_F12;
    case Qt::Key_F13:
        return VK_F13;
    case Qt::Key_F14:
        return VK_F14;
    case Qt::Key_F15:
        return VK_F15;
    case Qt::Key_F16:
        return VK_F16;
    case Qt::Key_F17:
        return VK_F17;
    case Qt::Key_F18:
        return VK_F18;
    case Qt::Key_F19:
        return VK_F19;
    case Qt::Key_F20:
        return VK_F20;
    case Qt::Key_F21:
        return VK_F21;
    case Qt::Key_F22:
        return VK_F22;
    case Qt::Key_F23:
        return VK_F23;
    case Qt::Key_F24:
        return VK_F24;
    case Qt::Key_Space:
        return VK_SPACE;
    case Qt::Key_Asterisk:
        return VK_MULTIPLY;
    case Qt::Key_Plus:
        return VK_ADD;
    case Qt::Key_Comma:
        return VK_SEPARATOR;
    case Qt::Key_Minus:
        return VK_SUBTRACT;
    case Qt::Key_Slash:
        return VK_DIVIDE;
    case Qt::Key_MediaNext:
        return VK_MEDIA_NEXT_TRACK;
    case Qt::Key_MediaPrevious:
        return VK_MEDIA_PREV_TRACK;
    case Qt::Key_MediaPlay:
        return VK_MEDIA_PLAY_PAUSE;
    case Qt::Key_MediaStop:
        return VK_MEDIA_STOP;
    case Qt::Key_VolumeDown:
        return VK_VOLUME_DOWN;
    case Qt::Key_VolumeUp:
        return VK_VOLUME_UP;
    case Qt::Key_VolumeMute:
        return VK_VOLUME_MUTE;

    case Qt::Key_0:
    case Qt::Key_1:
    case Qt::Key_2:
    case Qt::Key_3:
    case Qt::Key_4:
    case Qt::Key_5:
    case Qt::Key_6:
    case Qt::Key_7:
    case Qt::Key_8:
    case Qt::Key_9:
        return key;

    case Qt::Key_A:
    case Qt::Key_B:
    case Qt::Key_C:
    case Qt::Key_D:
    case Qt::Key_E:
    case Qt::Key_F:
    case Qt::Key_G:
    case Qt::Key_H:
    case Qt::Key_I:
    case Qt::Key_J:
    case Qt::Key_K:
    case Qt::Key_L:
    case Qt::Key_M:
    case Qt::Key_N:
    case Qt::Key_O:
    case Qt::Key_P:
    case Qt::Key_Q:
    case Qt::Key_R:
    case Qt::Key_S:
    case Qt::Key_T:
    case Qt::Key_U:
    case Qt::Key_V:
    case Qt::Key_W:
    case Qt::Key_X:
    case Qt::Key_Y:
    case Qt::Key_Z:
        return key;

    default:
        return 0;
    }
}

大脸猫

这个人虽然很勤快,但什么也没有留下!

文章评论

  • 唯一的小黄鸡

    哈哈 搞定了

    2024年2月22日
  • 唯一的小黄鸡

    大佬,为啥我抄你的大佬运行不了啊。。 加个QQ 解答下呗2602118005

    2024年2月22日