QT实现天气预报

1. MainWindow类设计的成员变量和方法

public:
    MainWindow(QWidget* parent = nullptr);
    ~MainWindow();

   protected:

形成文本菜单来用来右键关闭窗口
    void contextMenuEvent(QContextMenuEvent* event);

鼠标被点击之后此事件被调用

    void mousePressEvent(QMouseEvent *ev);

移动窗口
    void mouseMoveEvent(QMouseEvent* ev);
    //重写过滤器方法
    bool eventFilter(QObject *watched, QEvent *event);

private slots://信号槽函数
    void onReplied(QNetworkReply* reply);

    void on_btnSearch_clicked();

public:

    void getWeaterInfo(QString cityCode);
    //解析json数据
    void parseJson(QByteArray& byteArray);
    int parseString(QString str);
    //更新UI
    void UpdateUi();
    //检测空气质量
   int checkedQulity(int api);
    //绘制高低温曲线
    void paintHighCurve();
   void paintLowCurve();

   private:
    Ui::MainWindow* ui;

    QMenu* mExitMenu;   // 右键退出的菜单
    QAction* mExitAct;  // 退出的行为
    QPoint m_offset;//鼠标和左上角坐标的偏移距离
    QNetworkAccessManager *m_netAccessManager;
    Today m_today;
    Day m_day[7];

    //星期和日期
    QList<QLabel*> m_weekList;
    QList<QLabel*> m_dateList;

    //天气和天气图标
    QList<QLabel*> m_typeList;
    QList<QLabel*> m_typeIconList;

    //天气污染指数
    QList<QLabel*> m_ApiList;

    //风力和风向
    QList<QLabel*> m_FLList;
    QList<QLabel*> m_FXList;

把UI控件都放到QList集合里面

//将UI控件放到数组里边,方便使用循环进行处理m_dateList << ui->lblDate0 << ui->lblDate1 << ui->lblDate2 << ui->lblDate3 << ui->lblDate4 << ui->lblDate5;m_weekList << ui->lblWeek0 << ui->lblWeek1 << ui->lblWeek2 << ui->lblWeek3 << ui->lblWeek4 << ui->lblWeek5;m_ApiList << ui->lblQuality0 << ui->lblQuality1 << ui->lblQuality2 << ui->lblQuality3 << ui->lblQuality4 << ui->lblQuality5;m_typeList << ui->lblType0 << ui->lblType1 << ui->lblType2 << ui->lblType3 << ui->lblType4 << ui->lblType5;m_typeIconList << ui->lblTypeIcon0 << ui->lblTypeIcon1 << ui->lblTypeIcon2 << ui->lblTypeIcon3 << ui->lblTypeIcon4 << ui->lblTypeIcon5;m_FXList << ui->lblFx0 << ui->lblFx1 << ui->lblFx2 << ui->lblFx3 << ui->lblFx4 << ui->lblFx5;m_FLList << ui->lblFl0 << ui->lblFl1 << ui->lblFl2 << ui->lblFl3 << ui->lblFl4 << ui->lblFl5;

    QMap <QString,QString> m_typeMap;

2. 右键退出

void contextMenuEvent(QContextMenuEvent* event);

  mExitMenu->exec(QCursor::pos());event->accept();

QMenu* mExitMenu;   右键退出的菜单

 // 右键菜单：退出程序
    mExitMenu = new QMenu(this);//添加一个菜单框
    mExitAct = new QAction();
    mExitAct->setText(tr("退出"));
    mExitAct->setIcon(QIcon(":/res/close.png"));
    mExitMenu->addAction(mExitAct);//把这个行为设置到菜单里面去

    connect(mExitAct, &QAction::triggered, this, [=]() {
        qApp->exit(0); 
    });

3.存放天气信息的类

class Today
{
public:Today(){date = "2022-10-20";city = "广州";ganmao = "感冒指数";wendu = 0;shidu = "0%";pm25 = 0;quality = "无数据";type = "多云";fl = "2级";fx = "南风";high = 30;low = 18;}QString date;QString city;QString ganmao;int wendu;QString shidu;int pm25;QString quality;QString type;QString fx;QString fl;int high;int low;
};class Day
{
public:Day(){date = "2022-10-20";week = "周五";type = "多云";high = 0;low = 0;fx = "南风";fl = "2级";aqi = 0;}QString date;QString week;QString type;QString ymd;int high;int low;QString fx;QString fl;int aqi;
};

4.get请求数据

void MainWindow::getWeaterInfo(QString cityName)
{QString cityCode=weatherTool::getCityCode(cityName);qDebug()<<"cityCode"<<cityCode;QUrl url("http://t.weather.itboy.net/api/weather/city/"+cityCode);m_netAccessManager->get(QNetworkRequest(url));//发送get请求
}

5.重写void onReplied函数

void onReplied(QNetworkReply* reply);在get请求成功之后此函数被调用

void MainWindow::onReplied(QNetworkReply *reply)
{qDebug()<<"onReplied success";int status_code=reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toInt();qDebug()<<"参数： "<<reply->operation();qDebug()<<"状态码： "<<status_code;qDebug()<<"url： "<<reply->url();qDebug()<<"请求头： "<<reply->rawHeaderList();if(reply->error()!=QNetworkReply::NoError||status_code!=200){qDebug()<<reply->errorString().toLatin1().data();QMessageBox::warning(this,"天气预报","数据请求失败",QMessageBox::Ok);}else{QByteArray all=reply->readAll();qDebug()<<"read all : "<<all.data() ;parseJson(all);}reply->deleteLater();}

在此函数里把请求到的数据全部读出来

6.读出类之后在调用parseJson(all);来进行解析JSON数据

void MainWindow::parseJson(QByteArray &byteArray)
{QJsonParseError err;QJsonDocument doc=QJsonDocument::fromJson(byteArray,&err);if(err.error!=QJsonParseError::NoError){qDebug()<<"解析Json出错了";return ;}//Json对象,包括了请求的全部数据QJsonObject rootObj = doc.object();//qDebug() << rootObj;QJsonObject dataObj = rootObj.value("data").toObject();QJsonObject yesterdayObj = dataObj.value("yesterday").toObject();//Json数组,未来几天的数据QJsonArray forecastArray = dataObj.value("forecast").toArray();//1.解析日期和城市QString str = rootObj.value("time").toString();m_today.date= str.split(" ").at(0);qDebug()<<"今天:"<<m_today.date;m_today.city = rootObj.value("cityInfo").toObject().value("city").toString();//2.解析yesterdaym_day[0].date = yesterdayObj.value("date").toString();//日期m_day[0].aqi = yesterdayObj.value("aqi").toDouble();//空气质量,toDouble包括整数型m_day[0].type = yesterdayObj.value("type").toString();//天气类型m_day[0].week = yesterdayObj.value("week").toString();//星期m_day[0].ymd = yesterdayObj.value("ymd").toString();//完整年月日//解析最低温度和最高温度/*QString str = yesterdayObj.value("low").toString();//最低温度str = str.split(" ").at(1);//以空格为分割符,去除前面的文字,取出第二个X℃,str = str.left(str.length() - 1);//去除后面的摄氏度符号mDay[0].low = str.toInt();//传入最低温度str.clear();//清除内容str = yesterdayObj.value("high").toString();//最高温度str = str.split(" ").at(1);//以空格为分割符,去除前面的文字,取出第二个X℃,str = str.left(str.length() - 1);//去除后面的摄氏度符号mDay[0].high = str.toInt();//传入最高温度*///简化版m_day[0].low = parseString(yesterdayObj.value("low").toString());//最低温度m_day[0].high = parseString(yesterdayObj.value("high").toString());//最高温度m_day[0].fx = yesterdayObj.value("fx").toString();//风向m_day[0].fl = yesterdayObj.value("fl").toString();//风力//3.解析forecast中的6天数据for (int i = 0; i < 5; ++i) {QJsonObject forecastData = forecastArray[i].toObject();//跳过0,因为0已经赋值给昨天的数据了m_day[i + 1].date = forecastData.value("date").toString();//日期//qDebug()<<"time: "<<m_day[i + 1].date;m_day[i + 1].aqi = forecastData.value("aqi").toDouble();//空气质量,toDouble包括整数型m_day[i + 1].type = forecastData.value("type").toString();//天气类型m_day[i + 1].week = forecastData.value("week").toString();//星期m_day[i + 1].low = parseString(forecastData.value("low").toString());//最低温度m_day[i + 1].high = parseString(forecastData.value("high").toString());//最高温度m_day[i + 1].fx = forecastData.value("fx").toString();//风向m_day[i + 1].fl = forecastData.value("fl").toString();//风力m_day[i + 1].ymd = forecastData.value("ymd").toString();//完整年月日//ymd分割成MM/dd//QDateTime::fromString(forecastData.value("ymd").toString(), "yyyy-MM-dd").toString("MM/dd");//日期//qDebug() << i << mDay[i + 1].date << mDay[i + 1].aqi << mDay[i + 1].type << mDay[i + 1].week << mDay[i + 1].low << mDay[i + 1].high << mDay[i + 1].fx << mDay[i + 1].fl;//qDebug() << i << mDay[i].date;//qDebug() << mDay[i + 1].ymd;}//4.解析今天的数据m_today.shidu = dataObj.value("shidu").toString();m_today.quality = dataObj.value("quality").toString();m_today.ganmao = dataObj.value("ganmao").toString();m_today.pm25 = dataObj.value("pm25").toDouble();m_today.wendu = dataObj.value("wendu").toString().toInt();//qDebug() << dataObj;//qDebug() << mToday.shidu << mToday.quality << mToday.ganmao << mToday.pm25 << mToday.wendu;//注意:forecast中的第2个元素也是今天的数据m_today.type = m_day[1].type;qDebug()<<"今天的天气是： "<<m_today.type;m_today.low = m_day[1].low;m_today.high = m_day[1].high;m_today.fx = m_day[1].fx;m_today.fl = m_day[1].fl;//qDebug() << mToday.type << mToday.low << mToday.high << mToday.fx << mToday.fl;UpdateUi();//更新曲线在搜索城市完成后手动更新曲线ui->lblHighCurve->update();ui->lblLowCurve->update();
}

解析完JSON数据之后在更新ui（UpdateUi();）

7.更新UI

void MainWindow::UpdateUi()
{ui->lblDate->setText(QDateTime::fromString(m_today.date,"yyyyMMdd").toString("yyyy/MM/dd")+" "+m_day[1].week);ui->lblCity->setText(m_today.city);//更新今天数据ui->lblTypeIcon->setPixmap(m_typeMap[m_today.type]);//更新图片ui->lblTemp->setText(QString ::number(m_today.wendu));ui->lblType->setText(m_today.type);ui->lblLowHigh->setText(QString ::number(m_today.low)+"℃ ~ "+QString::number(m_today.high)+"℃");ui->lblGanMao->setText("感冒指数: "+m_today.ganmao);ui->lblWindFl->setText(m_today.fl);ui->lblWindFx->setText(m_today.fx);ui->lblPM25->setText(QString::number(m_today.pm25));ui->lblShiDu->setText(m_today.shidu);ui->lblQuality->setText(m_today.quality);//更新六天for(int i=0;i<6;i++){//更新日期和时间m_weekList[i]->setText("周"+m_day[i].week.right(1));//从右边取第一个ui->lblWeek0->setText("昨天");ui->lblWeek1->setText("今天");ui->lblWeek2->setText("明天");//         //把日期提取出来变成 10/10格式QStringList slist=m_day[i].ymd.split("-");qDebug()<<slist;m_dateList[i]->setText(slist.at(1)+"/"+slist.at(2));//更新天气类型m_typeList[i]->setText(m_day[i].type);m_typeIconList[i]->setPixmap(m_typeMap[m_day[i].type]);//更新图片
//空气质量switch (checkedQulity(m_day[i].aqi)) {case 1:m_ApiList[i]->setText("优");m_ApiList[i]->setStyleSheet("background-color: rgb(121,184,0);");break;case 2:m_ApiList[i]->setText("良");m_ApiList[i]->setStyleSheet("background-color: rgb(255,187,23);");break;case 3:m_ApiList[i]->setText("轻度");m_ApiList[i]->setStyleSheet("background-color: rgb(255,87,97);");break;case 4:m_ApiList[i]->setText("中度");m_ApiList[i]->setStyleSheet("background-color: rgb(235,17,27);");break;case 5:m_ApiList[i]->setText("重度");m_ApiList[i]->setStyleSheet("background-color: rgb(170,0,0);");break;case 6:m_ApiList[i]->setText("严重");m_ApiList[i]->setStyleSheet("background-color: rgb(110,0,0);");break;}//风力风向m_FXList[i]->setText(m_day[i].fx);m_FLList[i]->setText(m_day[i].fl);}}//检查空气质量
int MainWindow::checkedQulity(int aqi)
{if (aqi >= 0 && aqi <= 50) {return 1;}else if(aqi > 50 && aqi <= 100){return 2;}else if(aqi > 100 && aqi <= 150){return 3;}else if(aqi > 150 && aqi <= 200){return 4;}else if(aqi > 200 && aqi <= 250){return 5;}else{return 6;}return -1;
}

8.实现搜索框搜索城市

获取LeCity搜索框输入的数据

void MainWindow::on_btnSearch_clicked()
{QString cityName=ui->leCity->text();getWeaterInfo(cityName);
}

天气工具类

//天气工具类
class weatherTool{
private://内联静态变量 在占用调用处的内存inline static QMap<QString,QString> m_cityMap={};static void initCityMap(){QFile fd("E:\\code\\citycode.json");fd.open(QIODevice::ReadOnly|QIODevice::Text);QByteArray allJson=fd.readAll();fd.close();QJsonParseError err;//读出的数据转换为json的QJsonDocument doc=  QJsonDocument::fromJson(allJson,&err);if(err.error!=QJsonParseError::NoError||!doc.isArray()){//不是数组就错误qDebug()<<"json数据转换失败...";return;}  //转换成json数组QJsonArray rootArray=doc.array();for(int i=0;i<rootArray.size();i++){QString cityName = rootArray[i].toObject().value("city_name").toString();QString cityCode = rootArray[i].toObject().value("city_code").toString();//判断编号是否存在if(cityCode.size()>0){m_cityMap.insert(cityName,cityCode);}}}public :QString static getCityCode(QString cityName){qDebug()<<"cityName"<<cityName;if(m_cityMap.isEmpty()){qDebug()<< m_cityMap.isEmpty();initCityMap();}if(cityName==""){QMessageBox::warning(nullptr,"错误(null)","输入的城市不能为空...",QMessageBox::Ok);return "";}//在map寻找传入的城市名称,返回值可以遍历//返回的是map中的多个元素QMap<QString, QString>::iterator it = m_cityMap.find(cityName);//到结尾了,未找到,加上市,再搜一遍if (it == m_cityMap.end()) {it = m_cityMap.find(cityName + "市");}//找到了if (it != m_cityMap.end()) {qDebug()<<" if (it != m_cityMap.end())";return it.value();}QMessageBox::warning(nullptr,"城市名字错误","输入的城市名字错误...",QMessageBox::Ok);//否则return "";}};

读取这个文件里面的数据QFile fd("E:\\code\\citycode.json");把city_name和city_code取出来放到QMap集合里面去，之后在和输入的CityName进行查找获得city_code.