0x00 在C++代码在定义一个信号函数:“void sendData2UI(QString msg);”,该函数主要是将接收到的UDP消息发送到QML界面中
#ifndef UDPCLI_H
#define UDPCLI_H
#include <QObject>
#include <QUdpSocket>
#include <QString>
class UdpCli : public QObject
{
Q_OBJECT
public:
explicit UdpCli(QObject *parent = nullptr);
Q_INVOKABLE void sendMsg(QString msg);
void recvMsg();
signals:
void sendData2UI(QString msg);
private:
QUdpSocket* udpSocket;
};
#endif // UDPCLI_H
#include "udpcli.h"
#include <QHostAddress>
UdpCli::UdpCli(QObject *parent) : QObject(parent)
{
udpSocket = new QUdpSocket(this);
udpSocket->bind(QHostAddress::LocalHost, 9898);
connect(udpSocket, &QUdpSocket::readyRead, this, &UdpCli::recvMsg);
}
void UdpCli::sendMsg(QString msg)
{
udpSocket->writeDatagram(msg.toStdString().c_str(), msg.size(),
QHostAddress("127.0.01"), 19898);
}
void UdpCli::recvMsg()
{
QHostAddress sender;
quint16 senderPort;
while (udpSocket->hasPendingDatagrams())
{
QByteArray datagram;
datagram.resize(udpSocket->pendingDatagramSize());
udpSocket->readDatagram(datagram.data(), datagram.size(), &sender, &senderPort);
QString msg = QString::fromLocal8Bit(datagram);
qDebug() << msg;
sendData2UI("Recv[" + sender.toString() + ":" + QString::number(senderPort) + "] " + msg);
}
}
0x01 在QML代码中使用Connections创建C++对象的信号与QML中定义的槽函数连接
import QtQuick 2.14
import QtQuick.Window 2.14
import QtQuick.Controls 1.4
import QtQuick.Controls 2.12 as Controls
import QtQuick.Controls.Styles 1.4
import QtQuick.Controls.Material 2.12
// import com.HLD 1.0
import QtQml 2.14
Window {
visible: true;
minimumHeight: 480;
maximumHeight: 480;
minimumWidth: 640;
maximumWidth: 640;
title: qsTr("HLD.TableView")
color: Qt.rgba(127, 255, 170, 1.0)
Column{
anchors.centerIn: parent;
spacing: 10;
Row{
id: sendArea;
spacing: 10;
TextField {
id: inputField;
width: 300;
placeholderText: "Enter text";
style: TextFieldStyle {
background: Rectangle {
color: "#ffffff"
border.color: "#40E0D0"
radius: 4
}
}
}
Button{
id: btn;
text: "发送";
style: ButtonStyle {
background: Rectangle {
color: "#2196f3"
radius: 4;
}
label: Text {
text: btn.text
color: "#ffffff"
font.pixelSize: 16
}
}
onClicked: {
if(inputField.text.length > 0)
{
console.log(inputField.text);
UdpCli.sendMsg(inputField.text);
}
}
}
}
Text {
text: qsTr("接收数据:");
}
TextArea{
id: recvMsg;
width: sendArea.width;
readOnly: true;
}
Connections{
target: UdpCli;
function onSendData2UI(msg){
recvMsg.text += msg;
recvMsg.text += "\r\n";
console.log(msg);
}
}
}
}
#include <QGuiApplication>
#include <QQmlApplicationEngine>
#include <QQuickStyle>
#include <QMetaObject>
#include <QQmlContext>
#include "udpcli.h"
int main(int argc, char *argv[])
{
QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
QGuiApplication app(argc, argv);
QQuickStyle::setStyle("Material");
UdpCli m_udpCli;
/**
* @brief qmlRegisterSingletonInstance
* @param Url名
* @param 主版本
* @param 次版本
* @param Qml中控件名
* @param C++对象
*/
// qmlRegisterSingletonInstance("com.HLD", 1, 0, "UdpCli", &m_udpCli);
QQmlApplicationEngine engine;
const QUrl url(QStringLiteral("qrc:/main.qml"));
QObject::connect(&engine, &QQmlApplicationEngine::objectCreated,
&app, [url](QObject *obj, const QUrl &objUrl) {
if (!obj && url == objUrl)
QCoreApplication::exit(-1);
}, Qt::QueuedConnection);
auto context = engine.rootContext();
context->setContextProperty("UdpCli", &m_udpCli);
engine.load(url);
return app.exec();
}
效果演示:文章来源:https://www.toymoban.com/news/detail-573920.html
文章来源地址https://www.toymoban.com/news/detail-573920.html
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