我必须将项目从QT5降级到QT4,并且在执行此操作时会出现奇怪的缓冲区溢出错误。这是我的代码:
我像这样创建一个QThread:
thread = new QThread;
reader = new Reader();
reader->setParams(samplingRate);
reader->moveToThread(thread);
connect(thread, SIGNAL(started()), reader, SLOT(read()));
connect(reader, SIGNAL(finished()), thread, SLOT(quit()));
connect(thread, SIGNAL(finished()), this, SLOT(threadFinished()));
connect(reader, SIGNAL(finished()), reader, SLOT(deleteLater()));
connect(thread, SIGNAL(finished()), thread, SLOT(deleteLater()));
connect(reader, SIGNAL(errorMsg(QString)), this, SLOT(threadErrorMsg(QString)));
thread->start();
在我的帖子中,我有以下代码:
try {
while(condition) {
...something
}
} catch(Exception e) {
emit errorMsg("Error");
}
emit finished();
我主线程中的Slots看起来像这样:
void MainWindow::threadFinished() {
reader = NULL;
delete thread;
thread = NULL;
}
void MainWindow::threadErrorMsg(QString message) {
QMessageBox::critical(this, "Error", ("Error: " + message).toStdString().c_str(), QMessageBox::Ok);
}
所有这些在QT5中都运作良好。错误消息框已正确显示并且线程已被销毁。但是在QT4(4.8.1)中,当发生错误并发出errorMsg()时,我收到缓冲区溢出错误。如果我不发出errorMsg("错误")并且仅通过调用finished()来销毁线程,则不会发生缓冲区溢出。关于这里有什么问题的任何想法?
更新: 如果我没有访问threadErrorMsgit中的QString确实有效。像这样:
void MainWindow::threadErrorMsg(QString message) {
QMessageBox::critical(this, "Error", "Error", QMessageBox::Ok);
}
我做错了什么?
答案 0 :(得分:1)
void MainWindow::threadFinished() {
reader = NULL;
delete thread;
thread = NULL;
}
不建议直接在插槽中删除线程。你应该使用deleteLater函数。
thread->deleteLater();
但是,您已经在连接中设置了要删除的线程
connect(thread, SIGNAL(finished()), thread, SLOT(deleteLater()));
所以你现在试图删除它两次!
对于缓冲区溢出,我怀疑在发生错误之前某些内存已损坏。