C++ 如何为Qt-Quick解析JSON?
我试图做一个简单的编程,将JSON消息值从web解析到QtQuick JSON消息要解析:C++ 如何为Qt-Quick解析JSON?,c++,json,qt,qt5,qt-quick,C++,Json,Qt,Qt5,Qt Quick,我试图做一个简单的编程,将JSON消息值从web解析到QtQuick JSON消息要解析: [ { "id": 2, "name": "yahoo", "link": "http://www.yahoo.com/", "created_by": "superadmin", "create_time": "2015-03-12 14:45:21" }, { "id":
[
{
"id": 2,
"name": "yahoo",
"link": "http://www.yahoo.com/",
"created_by": "superadmin",
"create_time": "2015-03-12 14:45:21"
},
{
"id": 3,
"name": "Google",
"link": "http://www.google.com/",
"created_by": "superadmin",
"create_time": "2015-03-12 14:45:41"
},
{
"id": 4,
"name": "PS",
"link": "http://www.playstation.com",
"created_by": "superadmin",
"create_time": "2015-03-24 11:57:21"
}
]
以下是尝试解析这些数据的Qt代码main.cpp:
#include <QGuiApplication>
#include <QStringList>
#include <QNetworkReply>
#include <QNetworkRequest>
#include <QNetworkAccessManager>
#include <QtScript/QScriptEngine>
#include <QtScript/QScriptValueIterator>
#include <QJsonDocument>
#include <QJsonObject>
#include <QJsonArray>
#include <qqmlengine.h>
#include <qqmlcontext.h>
#include <qqml.h>
#include <QtQuick/qquickitem.h>
#include <QtQuick/qquickview.h>
#include <main.h>
QStringList Jsondata::datalistmethod() {
return datalist;
}
void Jsondata::onResult(QNetworkReply* reply)
{
QString data = (QString) reply->readAll();
QJsonDocument jsonResponse = QJsonDocument::fromJson(data.toUtf8());
QJsonObject jsonObject = jsonResponse.object();
foreach (const QJsonValue & value, jsonObject) {
QJsonObject obj = value.toObject();
datalist.append(obj["name"].toString());
datalist.append(obj["link"].toString());
}
}
int main(int argc, char ** argv)
{
QGuiApplication app(argc, argv);
Jsondata jsondata;
// Now parse this JSON according to your needs !
QNetworkAccessManager networkManager;
networkManager.setNetworkAccessible(QNetworkAccessManager::Accessible);
QUrl url("http://dbs.wasonicsystem.com/gta_test/api/web/v1/links");
QNetworkRequest request;
request.setUrl(url);
Jsondata::connect(&networkManager, SIGNAL(finished(QNetworkReply*)), &jsondata, SLOT(onResult(QNetworkReply*)));
networkManager.get(request); // GET
QStringList datalist;
datalist = jsondata.datalistmethod();
QQuickView view;
QQmlContext *ctxt = view.rootContext();
ctxt->setContextProperty("myModel", QVariant::fromValue(datalist));
view.setSource(QUrl("qrc:main.qml"));
view.show();
return app.exec();
}
结果:
onResult仍然没有调用。所以没有返回数据列表
我不知道这个
QObject::connect
有什么问题。如果您能帮助我修复此错误,我将不胜感激。我终于找到了解决此问题的方法。下面是代码片段
main.cpp
#include <QGuiApplication>
#include <QStringList>
#include <qqmlengine.h>
#include <qqmlcontext.h>
#include <qqml.h>
#include <QtQuick/qquickitem.h>
#include <QtQuick/qquickview.h>
#include <jsondata.h>
int main(int argc, char ** argv)
{
QGuiApplication app(argc, argv);
QStringList datalist;
Jsondata jsondata;
jsondata.datalistmethod();
datalist = jsondata.datalist;
QQuickView view;
QQmlContext *ctxt = view.rootContext();
ctxt->setContextProperty("myModel", QVariant::fromValue(datalist));
view.setSource(QUrl("qrc:main.qml"));
view.show();
return app.exec();
}
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int main(int argc,字符**argv)
{
QGUI应用程序应用程序(argc、argv);
QStringList数据表;
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jsondata.datalistmethod();
datalist=jsondata.datalist;
QQuickView视图;
QQmlContext*ctxt=view.rootContext();
ctxt->setContextProperty(“myModel”,QVariant::fromValue(datalist));
view.setSource(qrl(“qrc:main.qml”);
view.show();
返回app.exec();
}
jsondata.h
#ifndef JSONDATA_H
#define JSONDATA_H
#include <QObject>
#include <QNetworkReply>
#include <QStringList>
#include <QNetworkAccessManager>
class Jsondata : public QObject {
Q_OBJECT
public:
QStringList datalist;
explicit Jsondata(QObject *parent =0);
void datalistmethod();
public slots:
void onResult (QNetworkReply*);
private:
QNetworkAccessManager *manager;
};
\ifndef JSONDATA\u H
#定义JSONDATA_H
#包括
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类Jsondata:公共QObject{
Q_对象
公众:
QStringList数据表;
显式Jsondata(QObject*parent=0);
void datalistmethod();
公众时段:
void onResult(QNetworkReply*);
私人:
QNetworkAccessManager*管理器;
};
jsondata.cpp
#include "jsondata.h"
#include <QNetworkReply>
#include <QNetworkRequest>
#include <QNetworkAccessManager>
#include <QJsonDocument>
#include <QJsonObject>
#include <QJsonArray>
#include <QEventLoop>
#include <QtQuick/qquickitem.h>
#include <QtQuick/qquickview.h>
#include <QTimer>
#include <qqmlengine.h>
#include <qqmlcontext.h>
#include <qqml.h>
Jsondata::Jsondata(QObject *parent) :
QObject(parent)
{
}
void Jsondata::datalistmethod() {
// Now parse this JSON according to your needs !
manager = new QNetworkAccessManager(this);
manager->setNetworkAccessible(QNetworkAccessManager::Accessible);
QNetworkRequest request;
QEventLoop eventloop;
QUrl url("http://***/api/web/v1/links");
request.setUrl(url);
QNetworkReply *reply = manager->get(request);
connect(reply, SIGNAL(finished()), &eventloop, SLOT(quit()));
eventloop.exec();
onResult(reply);
}
void Jsondata::onResult(QNetworkReply* reply)
{
QString data = (QString) reply->readAll();
qDebug() << "Response:" << data;
QJsonDocument jsonResponse = QJsonDocument::fromJson(data.toUtf8());
QJsonArray jsonArray = jsonResponse.array();
foreach (const QJsonValue & value, jsonArray) {
QJsonObject obj = value.toObject();
datalist.append(obj["name"].toString());
datalist.append(obj["link"].toString());
}
}
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Jsondata::Jsondata(QObject*父对象):
QObject(父对象)
{
}
void Jsondata::datalistmethod(){
//现在根据您的需要解析这个JSON!
manager=新的QNetworkAccessManager(此);
管理器->设置网络可访问(QNetworkAccessManager::可访问);
QNetworkRequest请求;
QEventLoop事件循环;
QUrl url(“http://***/api/web/v1/links”);
setUrl(url);
QNetworkReply*reply=manager->get(请求);
连接(应答、信号(finished())、&eventloop、插槽(quit());
eventloop.exec();
结果(答复);
}
void Jsondata::onResult(QNetworkReply*reply)
{
QString data=(QString)reply->readAll();
qDebug()您正在尝试创建一个到一个对象的连接,该对象不是从QObject
(您的JsonData
类)派生的。当然,您可以只看文档:调用QObject::connect(&networkManager,SIGNAL(finished(QNetworkReply*)非常奇怪,这个插槽(onResult(QNetworkReply*))
内部onResult
插槽。看起来应用程序的逻辑已中断。感谢您的回答。我尝试从Qobject派生。它修复了错误。但我仍然无法从json消息中获得结果,因为我发现它没有调用onResult方法。我修改了发布的代码,并添加了main.qml供参考。我希望任何人都能请帮助我完成。谢谢。大家好,我使用另一种方式再次编辑了我的问题,但在连接过程中仍然没有触发onResult。请告诉我您是否有任何解决问题的想法。谢谢。您的代码中有很多失败的机会,并且没有错误检查。
#ifndef JSONDATA_H
#define JSONDATA_H
#include <QObject>
#include <QNetworkReply>
#include <QStringList>
#include <QNetworkAccessManager>
class Jsondata : public QObject {
Q_OBJECT
public:
QStringList datalist;
explicit Jsondata(QObject *parent =0);
void datalistmethod();
public slots:
void onResult (QNetworkReply*);
private:
QNetworkAccessManager *manager;
};
#include "jsondata.h"
#include <QNetworkReply>
#include <QNetworkRequest>
#include <QNetworkAccessManager>
#include <QJsonDocument>
#include <QJsonObject>
#include <QJsonArray>
#include <QEventLoop>
#include <QtQuick/qquickitem.h>
#include <QtQuick/qquickview.h>
#include <QTimer>
#include <qqmlengine.h>
#include <qqmlcontext.h>
#include <qqml.h>
Jsondata::Jsondata(QObject *parent) :
QObject(parent)
{
}
void Jsondata::datalistmethod() {
// Now parse this JSON according to your needs !
manager = new QNetworkAccessManager(this);
manager->setNetworkAccessible(QNetworkAccessManager::Accessible);
QNetworkRequest request;
QEventLoop eventloop;
QUrl url("http://***/api/web/v1/links");
request.setUrl(url);
QNetworkReply *reply = manager->get(request);
connect(reply, SIGNAL(finished()), &eventloop, SLOT(quit()));
eventloop.exec();
onResult(reply);
}
void Jsondata::onResult(QNetworkReply* reply)
{
QString data = (QString) reply->readAll();
qDebug() << "Response:" << data;
QJsonDocument jsonResponse = QJsonDocument::fromJson(data.toUtf8());
QJsonArray jsonArray = jsonResponse.array();
foreach (const QJsonValue & value, jsonArray) {
QJsonObject obj = value.toObject();
datalist.append(obj["name"].toString());
datalist.append(obj["link"].toString());
}
}