Qt工作笔记-通过C++使widgets与QQuick交互（包含qml界面对象与C++对象映射）

目录

理论及程序运行

源码

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理论及程序运行

这里要注意，通过qmlRegisterType函数去注册一个QML类！

下面再指明一个关键的问题，如何把QML界面的对象映射到C++呢！

可以有如下的处理：

通过这个函数：

QObject *pRoot = (QObject*)ui->quickWidget->rootObject();

 

还有几种方法：

注册的QML类也是具有QObject和元对象的性质的：

通过设置ObjectName（这个要唯一）

C++映射的时候通过

qDebug() << list[4]->objectName();

即可映射成功！

 

程序运行截图如下：

 

源码

文件结构如下：

源码如下：

getmsg.h

#ifndef GETMSG_H
#define GETMSG_H

#include 

class GetMsg : public QObject
{
    Q_OBJECT
    Q_PROPERTY(QString text READ text WRITE setText)
public:
    GetMsg(QObject *parent = 0);

    QString text() const;
    void setText(const QString &text);

signals:
    void textChanged(QString str);

private:
    QString m_text;
};

#endif // GETMSG_H

widget.h

#ifndef WIDGET_H
#define WIDGET_H

#include 

class GetMsg;

namespace Ui {
class Widget;
}

class Widget : public QWidget
{
    Q_OBJECT

public:
    explicit Widget(QWidget *parent = 0);
    ~Widget();

protected:
    void getMsgInfo();

protected slots:
    void textChanged(const QString &str);

private:
    Ui::Widget *ui;
    GetMsg *m_data;
};

#endif // WIDGET_H

getmsg.cpp

#include "getmsg.h"
#include 

GetMsg::GetMsg(QObject *parent) : QObject(parent)
{
    m_text = "";
}

QString GetMsg::text() const
{
    return m_text;
}

void GetMsg::setText(const QString &text)
{
    m_text = text;
    emit textChanged(m_text);
}

main.cpp

#include "widget.h"
#include 

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    Widget w;
    w.show();

    return a.exec();
}

widget.cpp

#include "widget.h"
#include "ui_widget.h"
#include "getmsg.h"

#include 
#include 
#include 
#include 
#include 
#include 


Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    ui->setupUi(this);

    //registartion
    qmlRegisterType("GetMsg", 1, 0, "GetMsg");
    ui->quickWidget->setSource(QUrl("qrc:/main.qml"));
    this->setWindowTitle("CSDN IT1995");

    QObject *pRoot = (QObject*)ui->quickWidget->rootObject();

    const QObjectList list = pRoot->children();
    m_data = static_cast(list[4]);
    qDebug() << list[4]->metaObject()->className();
    qDebug() << list[4]->objectName();
    connect(m_data, SIGNAL(textChanged(QString)), this, SLOT(textChanged(QString)));
}

Widget::~Widget()
{
    delete ui;
}

void Widget::getMsgInfo()
{

}

void Widget::textChanged(const QString &str)
{
    QString currentData = QDateTime::currentDateTime().toString("hh:mm:ss") + " ";
    currentData.append(str);
    ui->textEdit->append(currentData);
}

main.qml

import QtQuick 2.4
import GetMsg 1.0


Item {

    id: box

    Rectangle{

        id: redSquare
        width: 240; height: 120
        anchors.top: parent.top; anchors.left: parent.left; anchors.margins: 50
        color: "red"
        //opacity

        Text{

            text: "Click"
            font.pixelSize: 16
            anchors.centerIn: parent
        }

        MouseArea{

            id: readSquareMouseArea
            anchors.fill: parent
            hoverEnabled: true
            property string buttonID

            //Value 'All.Buttons' is eqivalent to:
            //'Qt::LeftButton | Qt::RightButton | Qt::MiddleButton  .... | Qt::ExtraButton24'
            acceptedButtons: Qt.AllButtons

            onPressed: {
                if (mouse.button === Qt.LeftButton)
                    buttonID = 'LeftButton'
                else if (mouse.button === Qt.RightButton)
                    buttonID = 'RightButton'
                else if (mouse.button === Qt.MidButton)
                    buttonID = 'MiddleButton'
                else if (mouse.button === Qt.BackButton)
                    buttonID = 'BackButton'
                else if (mouse.button === Qt.ForwardButton)
                    buttonID = 'ForwardButton'
                else if (mouse.button === Qt.TaskButton)
                    buttonID = 'TaskButton'
                else if (mouse.button === Qt.ExtraButton4)
                    buttonID = 'ExtraButton4'
                else if (mouse.button === Qt.ExtraButton5)
                    buttonID = 'ExtraButton5'
                else if (mouse.button === Qt.ExtraButton6)
                    buttonID = 'ExtraButton6'
                else if (mouse.button === Qt.ExtraButton7)
                    buttonID = 'ExtraButton7'
                else if (mouse.button === Qt.ExtraButton8)
                    buttonID = 'ExtraButton8'
                else if (mouse.button === Qt.ExtraButton9)
                    buttonID = 'ExtraButton9'
                else if (mouse.button === Qt.ExtraButton10)
                    buttonID = 'ExtraButton10'
                else if (mouse.button === Qt.ExtraButton11)
                    buttonID = 'ExtraButton11'
                else if (mouse.button === Qt.ExtraButton12)
                    buttonID = 'ExtraButton12'
                else if (mouse.button === Qt.ExtraButton13)
                    buttonID = 'ExtraButton13'
                else if (mouse.button === Qt.ExtraButton14)
                    buttonID = 'ExtraButton14'
                else if (mouse.button === Qt.ExtraButton15)
                    buttonID = 'ExtraButton15'
                else if (mouse.button === Qt.ExtraButton16)
                    buttonID = 'ExtraButton16'
                else if (mouse.button === Qt.ExtraButton17)
                    buttonID = 'ExtraButton17'
                else if (mouse.button === Qt.ExtraButton18)
                    buttonID = 'ExtraButton18'
                else if (mouse.button === Qt.ExtraButton19)
                    buttonID = 'ExtraButton19'
                else if (mouse.button === Qt.ExtraButton20)
                    buttonID = 'ExtraButton20'
                else if (mouse.button === Qt.ExtraButton21)
                    buttonID = 'ExtraButton21'
                else if (mouse.button === Qt.ExtraButton22)
                    buttonID = 'ExtraButton22'
                else if (mouse.button === Qt.ExtraButton23)
                    buttonID = 'ExtraButton23'
                else if (mouse.button === Qt.ExtraButton24)
                    buttonID = 'ExtraButton24'

                info.text = 'Press (' + buttonID + ' shift = '
                        + (mouse.modifiers & Qt.ShiftModifier ? 'true' : 'false') + ")"

                var posInBox = redSquare.mapToItem(box, mouse.x, mouse.y)
                posInfo.text = '红色方框内坐标: ' + mouse.x + ',' +mouse.y + '\n'
                               + 'quickwidgets窗口坐标: ' +  + posInBox.x + ' ,' +posInBox.y
                data.text = info.text + '\n' + posInfo.text;
            }

            onReleased: {

                btn.text = 'Released (isClick = ' + mouse.isClick + ' wasHeld = ' + mouse.wasHeld + ')'
                posInfo.text = ''
            }

            onPressAndHold: btn.text = 'Press and hold'
            onClicked: btn.text = 'Clicked (wasHeld=' + mouse.wasHeld + ')'
            onDoubleClicked: btn.text = 'Double clicked'
        }
    }


    Text{

        id: posInfo
        anchors.bottom: parent.bottom
        anchors.horizontalCenter: parent.horizontalCenter
        anchors.margins: 20
    }

    Text{

        id: btn
        anchors.bottom: posInfo.top
        anchors.horizontalCenter: parent.horizontalCenter
        anchors.margins: 20
    }

    Text{

        id: info
        anchors.bottom: btn.top
        anchors.horizontalCenter: parent.horizontalCenter
        anchors.margins: 20
    }

    GetMsg{
        objectName: 'GetInfo'
        id: data
    }

}

widget.ui的界面是这样的：