qt 信号槽的执行流程

 

mainwindow.h

#include "stdio.h"

class MainWindow : public QMainWindow
{
    Q_OBJECT

......
public:
signals:
    void testsignal(int i,float j);
public
slots:
    void testslot(int i,float j){printf("slot\n");};
};

////////////////////////////
mainwindow.cpp

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent), ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    connect(this,SIGNAL(testsignal(int,float)),SLOT(testslot(int,float)));
    emit testsignal(0,1.0);
}

emit testsignal(0,1.0);会进入
///////////////////////////////////////
moc_mainwindow.cpp
void MainWindow::testsignal(int _t1, float _t2)
{
    void *_a[] = { 0, const_cast<void*>(reinterpret_cast<const void*>(&_t1)), const_cast<void*>(reinterpret_cast<const void*>(&_t2)) };
    QMetaObject::activate(this, &staticMetaObject, 0, _a);
}

int MainWindow::qt_metacall(QMetaObject::Call _c, int _id, void **_a)
{
    _id = QMainWindow::qt_metacall(_c, _id, _a);
    if (_id < 0)
        return _id;
    if (_c == QMetaObject::InvokeMetaMethod) {
        switch (_id) {
        case 0: testsignal((*reinterpret_cast< int(*)>(_a[1])),(*reinterpret_cast< float(*)>(_a[2]))); break;
        case 1: testslot((*reinterpret_cast< int(*)>(_a[1])),(*reinterpret_cast< float(*)>(_a[2]))); break;
        default: ;
        }
        _id -= 2;
    }
    return _id;
}