一个类发出一个信号，一个类，用connect连接槽，为啥连不上呢？ [复制链接]

------------------------------------------class winsdk
winsdk::winsdk()
{
    signaltest();
}
void winsdk::signaltest()
{
        qDebug()<<"[3G][winsdk]testing emit signal>>>>>>>";
             emit writeDatabaseSignal();
        qDebug()<<"[3G][winsdk]testing emit signal>>>>>>>";
}
------------------------------------------class MainWindow

MainWindow::MainWindow
{
        winsdk *winSDK = new winsdk;
        connect(winSDK,SIGNAL(writeDatabaseSignal()),this,SLOT(writeDatabase()));//qDebug  result is true.
}
void MainWindow::writeDatabase(/*QString string*/)
{
    qDebug()<<"[3G][MainWindow]__WRITEDATABASE__in>>>>>>>>>>>>>>>>>>";
}
这是怎么回事呢？先谢过了～！～！～！
运行结果：
[3G][winsdk]testing emit signal>>>>>>>
[3G][winsdk]testing emit signal>>>>>>>
connect result true

引用楼主jn200002于2010-05-19 10:26发表的 一个类发出一个信号，一个类，用connect连接槽，为啥连不上呢？ :
------------------------------------------class winsdk
winsdk::winsdk()
{
    signaltest();
}
void winsdk::signaltest()
{
        qDebug()<<"[3G][winsdk]testing emit signal>>>>>>>";
             emit writeDatabaseSignal();
        qDebug()<<"[3G][winsdk]testing emit signal>>>>>>>";
}
------------------------------------------class MainWindow
MainWindow::MainWindow
{
        winsdk *winSDK = new winsdk;
        connect(winSDK,SIGNAL(writeDatabaseSignal()),this,SLOT(writeDatabase()));//qDebug  result is true.
}
void MainWindow::writeDatabase(/*QString string*/)
{
    qDebug()<<"[3G][MainWindow]__WRITEDATABASE__in>>>>>>>>>>>>>>>>>>";
}
.......

搞清楚那个执行在前，那个在后！

解决：

要在connect之后，再调用一次发出信号的函数。。。否则第一次发出的信号因为还没有建立连接会失效。

引用第1楼dbzhang800于2010-05-19 11:29发表的  :
搞清楚那个执行在前，那个在后！

晕，多谢～ ！～！