话接上文。笔者为了方便使用Lua,自己编写了一个Lua的类。主要代码如下:
QLua.h
1 #ifndef QLUA_H 2 #define QLUA_H 3 4 // own 5 #include "include/lua.hpp" 6 7 // qt 8 #include <QObject> 9 #include <QFile> 10 #include <QDebug> 11 12 #include <QWidget> 13 #include <QLineEdit> 14 #include <QPushButton> 15 #include <QMessageBox> 16 17 class QLua : public QObject 18 { 19 Q_OBJECT 20 public: 21 QLua(QObject *parent = 0); 22 ~QLua(); 23 24 // lua 25 void init(); 26 void close(); 27 28 void pushFunction(QString funcName, lua_CFunction func); 29 30 void beginModule(QString); 31 void addType(QString, lua_CFunction deleteFunc); 32 void moduleTypeFunction(QString, lua_CFunction); 33 void endModule(); 34 35 void run(QString); 36 signals: 37 38 public slots: 39 40 private: 41 lua_State *luaState; 42 43 bool isStartModule; 44 }; 45 46 #endif // QLUA_H
QLua.cpp
1 #include "qlua.h" 2 3 QLua::QLua(QObject *parent) : 4 QObject(parent) 5 , luaState(NULL) 6 , isStartModule(false) 7 { 8 init(); 9 } 10 11 QLua::~QLua() 12 { 13 close(); 14 } 15 16 void QLua::init() 17 { 18 luaState = luaL_newstate(); 19 luaL_openlibs(luaState); 20 } 21 22 void QLua::close() 23 { 24 if(luaState != NULL) 25 { 26 lua_close(luaState); 27 luaState = NULL; 28 } 29 } 30 31 void QLua::pushFunction(QString funcName, lua_CFunction func) 32 { 33 if (funcName.isEmpty()) return; 34 if (func == NULL) return; 35 36 lua_pushcfunction(luaState, func); 37 lua_setglobal(luaState, funcName.toLocal8Bit().data()); 38 } 39 40 void QLua::beginModule(QString name) 41 { 42 if(luaState == NULL) return; 43 44 if (isStartModule == false) 45 { 46 tolua_open(luaState); 47 tolua_module(luaState, NULL, 0); 48 isStartModule = true; 49 } 50 51 const char *str = name.isEmpty()? NULL : name.toLocal8Bit().data(); 52 tolua_beginmodule(luaState, str); 53 } 54 55 void QLua::addType(QString name, lua_CFunction deleteFunc) 56 { 57 if (luaState == NULL) return; 58 if (name.isEmpty()) return; 59 if (deleteFunc == NULL) return; 60 61 tolua_usertype(luaState, name.toLocal8Bit().data()); 62 const char *str = name.toLocal8Bit().data(); 63 tolua_cclass(luaState, str, str, "", deleteFunc); 64 beginModule(name); 65 } 66 67 void QLua::moduleTypeFunction(QString name, lua_CFunction func) 68 { 69 if(luaState == NULL) return ; 70 if (name.isEmpty()) return; 71 72 const char *str = name.toLocal8Bit().data(); 73 tolua_function(luaState, str, func); 74 } 75 76 void QLua::endModule() 77 { 78 tolua_endmodule(luaState); 79 } 80 81 void QLua::run(QString str) 82 { 83 luaL_loadbuffer(luaState, str.toLocal8Bit().data(), str.length(), "line"); 84 lua_pcall(luaState, 0, 0, 0); 85 }
QLua类可以方便的实现一些简单的Lua操作,如初始化,关闭,运行Lua代码,绑定函数等。
笔者目前想做到的是能在Lua代码中自有的生成Qt对象,然后能连接Qt原生对象的信号与槽。那么如何实现呢?
Qt中连接信号与槽的函数是QObject::connect(QObject * a, SIGNAL(), QObject * b, SLOT())。首先,我们要弄清楚SIGNAL和SLOT到底是什么。
从connect的参数列表中,我们可以很清晰的看到SIGNAL和SLOT的结果都是char*类型的字符串。我们可以直接在SIGNAL上点右键,转到SIGNAL的定义。或者做个简单的实验。测试如下Qt代码:
qDebug() << QString::fromLocal8Bit(SIGNAL(clicked())); qDebug() << QString::fromLocal8Bit(SLOT(close()));
得到的结果很有意思:
"2clicked()" "1close()"
简单总结就是我们只要传入函数名的字符串,加上前缀即可。SIGNAL的前缀是2,SLOT的前缀是1。
这样我们就可以实现在Lua中的connect函数了。仍在使用C++编写,然后绑定到Lua里。如下:
1 static int connect(lua_State* state) 2 { 3 QObject * a = (QObject*)tolua_tousertype(state, 1, 0); 4 const char * signal = tolua_tostring(state, 2, 0); 5 QObject * b = (QObject*)tolua_tousertype(state, 3, 0); 6 const char * slot = tolua_tostring(state, 4, 0); 7 8 QObject::connect(a, QString("2%0").arg(signal).toLocal8Bit().data(), 9 b, QString("1%0").arg(slot).toLocal8Bit().data()); 10 }
绑定时可以使用上面的QLua类:
lua.pushFunction("connect", connect);
完整main.cpp代码如下:
#include "include/lua.hpp" #include "qlua.h" #include <QWidget> #include <QApplication> #include <QFile> #include <QDebug> static int test(lua_State* state) { QPushButton* a = (QPushButton*)tolua_tousertype(state, 1, 0); if(a) a->show(); } static int connect(lua_State* state) { QObject * a = (QObject*)tolua_tousertype(state, 1, 0); const char * signal = tolua_tostring(state, 2, 0); QObject * b = (QObject*)tolua_tousertype(state, 3, 0); const char * slot = tolua_tostring(state, 4, 0); QObject::connect(a, QString("2%0").arg(signal).toLocal8Bit().data(), b, QString("1%0").arg(slot).toLocal8Bit().data()); } static int tolua_new_QWidget(lua_State* state) { QWidget* widget = new QWidget(); tolua_pushusertype(state, widget, "QWidget"); return 1; } static int tolua_delete_QWidget(lua_State* state) { qDebug() << "delete Start"; QWidget* widget = (QWidget* )tolua_tousertype(state, 1, 0); if(NULL != widget) { qDebug() << "delete~"; widget->close(); delete widget; } return 1; } static int tolua_Show_QWidget(lua_State* state) { QWidget* widget = (QWidget* )tolua_tousertype(state, 1, 0); if(widget != NULL) { widget->show(); } return 1; } static int tolua_new_QPushButton(lua_State* state) { QPushButton* button = new QPushButton(); tolua_pushusertype(state, button, "QPushButton"); return 1; } static int tolua_delete_QPushButton(lua_State* state) { QPushButton* button = (QPushButton* )tolua_tousertype(state, 1, 0); if(NULL != button) { button->close(); delete button; } return 1; } static int tolua_Show_QPushButton(lua_State* state) { QPushButton* button = (QPushButton* )tolua_tousertype(state, 1, 0); if(button != NULL) { button->show(); } return 1; } static int tolua_setText_QPushButton(lua_State* state) { QPushButton* button = (QPushButton* )tolua_tousertype(state, 1, 0); const char * text = tolua_tostring(state, 2, 0); if(button != NULL) { button->setText(QString::fromLocal8Bit(text)); } return 1; } static int tolua_Resize_QWidget(lua_State* state) { QWidget* widget = (QWidget* )tolua_tousertype(state, 1, 0); double a = tolua_tonumber(state, 2, 0); double b = tolua_tonumber(state, 3, 0); if(widget) { widget->resize((int)a, (int)b); } return 1; } static int QApplication_instance(lua_State* state) { tolua_pushusertype(state, QApplication::instance(), "QApplication"); return 1; } static int QApplication_quit(lua_State* state) { QApplication * app = (QApplication *)tolua_tousertype(state, 1, 0); if(app) app->quit(); return 1; } static int QApplication_delete(lua_State*) { return 1; } int main(int argc, char * argv[]) { Q_INIT_RESOURCE(resources); QApplication a(argc, argv); QLua lua; lua.beginModule(""); lua.addType("QWidget", tolua_delete_QWidget); lua.moduleTypeFunction("new", tolua_new_QWidget); lua.moduleTypeFunction("show", tolua_Show_QWidget); lua.moduleTypeFunction("resize", tolua_Resize_QWidget); lua.endModule(); lua.addType("QPushButton", tolua_delete_QPushButton); lua.moduleTypeFunction("new", tolua_new_QPushButton); lua.moduleTypeFunction("show", tolua_Show_QPushButton); lua.moduleTypeFunction("setText", tolua_setText_QPushButton); lua.endModule(); lua.addType("QApplication", QApplication_delete); lua.moduleTypeFunction("instance", QApplication_instance); lua.moduleTypeFunction("quit", QApplication_quit); lua.endModule(); lua.endModule(); lua.pushFunction("test", test); lua.pushFunction("connect", connect); // 读取资源文件 QFile file("://test.lua"); file.open(QIODevice::ReadOnly | QIODevice::Text); QTextStream in(&file); in.setCodec("UTF-8"); // 执行 lua.run(in.readAll()); return a.exec(); }
test.lua代码如下:
widget = QWidget:new() widget:show() button = QPushButton:new() button:setText("China") button:show() connect(button, "clicked()", widget, "close()") connect(button, "clicked()", button, "close()") print("run over")
程序运行结果如下:
点击China按钮,button和widget的窗口都会关闭。
至此,已经实现了连接 Qt 对象的信号与槽。
如果继续做下去,完全可以实现在Lua脚本中使用Qt的类和对象,写出Lua的Gui程序。
附完整代码工程文件:http://pan.baidu.com/s/1ntmFdjj
附个偶的博客地址:http://www.cnblogs.com/IT-BOY/