QT间进程通信之共享内存

#include "mainwidget.h" #include "ui_mainwidget.h" #include <QMessageBox> MainWidget::MainWidget(QWidget *parent) : QWidget(parent),sendsharedMem("SHAREFILE"),recvsharedMem("SHAREFILE"), ui(new Ui::MainWidget) { ui->setupUi(this); mythread = new MyThread; connect(mythread,SIGNAL(signal()),this,SLOT(recvDate())); connect(ui->pushButton, SIGNAL(clicked()), SLOT(loadFromSharedMem())); ui->textEdit_2->setEnabled(false); } void MainWidget::loadFromSharedMem() { if (sendsharedMem.isAttached()) { sendsharedMem.detach(); } bool ok; QString text = ui->textEdit->toPlainText(); ok=true; if(ok && text.length()) { QBuffer buffer; buffer.open(QBuffer::ReadWrite); QDataStream out(&buffer); out << text; int size = buffer.size(); if (!sendsharedMem.create(size)) { return; } sendsharedMem.lock(); char *to = (char*)sendsharedMem.data(); const char *from = buffer.data().data(); memcpy(to, from, qMin(sendsharedMem.size(), size)); sendsharedMem.unlock(); } else { QMessageBox::warning(this,tr("Error"),tr("You must provide some texts")); } } void MainWidget::recvDate() { if (!recvsharedMem.attach()) { ui->textEdit_2->setText("No Share Data"); return; } QBuffer buffer; QDataStream in(&buffer); QString text; recvsharedMem.lock(); buffer.setData((char*)recvsharedMem.constData(), recvsharedMem.size()); buffer.open(QBuffer::ReadOnly); in >> text; recvsharedMem.unlock(); recvsharedMem.detach(); ui->textEdit_2->setText(text); } MainWidget::~MainWidget() { delete ui; } void MainWidget::on_pushButton_2_clicked() { mythread->start(); } void MainWidget::on_pushButton_3_clicked() { exit(0); }