Qt Qml嵌入Widget以及Qml与Widget交互

这里是在Win10下,使用Qt5.7.0(cpp+qml)实现Qml嵌入Widget以及Qml与Widget交互。

QQuickWidget类,可以解决此问题。

1、先在pro是加入

QT += quickwidgets

2、新建QmlWidget类,并继承QWidget。

main.cpp如下

#include <QApplication>
#include "qmlwidget.h"

int main(int argc, char *argv[]) {
    QApplication app(argc, argv);
    QmlWidget qmlWidget;
    return app.exec();
}

3、qmlwidget.h如下

#ifndef QMLWIDGET_H
#define QMLWIDGET_H
#include <QQuickWidget>
#include <QQmlEngine>
#include <QVBoxLayout>

class QmlWidget : public QWidget
{
    Q_OBJECT
public:
    explicit QmlWidget(QWidget *parent = 0);
private:
    QVBoxLayout * layout;
    QQuickWidget * quickWidget;
signals:
    void sigWidget(void);
public slots:
    void slotWidget(void);
    void btnClicked(void);
};

#endif // QMLWIDGET_H

4、qmlwidget.cpp如下

#include "qmlwidget.h"
#include <QDebug>
#include <QPushButton>
QmlWidget::QmlWidget(QWidget *parent) : QWidget(parent) {
    quickWidget = new QQuickWidget();
    quickWidget->setSource(QUrl("qrc:///main.qml"));

    layout = new QVBoxLayout(this);
    QPushButton *btn1 = new QPushButton(this);
    btn1->setText("widget btn");
    layout->addWidget(btn1);

    connect(btn1,SIGNAL(clicked(bool)),this,SLOT(btnClicked()));
    QObject * obj = (QObject*)quickWidget->rootObject();
    connect(obj,SIGNAL(qmlClicked()),this,SLOT(slotWidget()));
    connect(this,SIGNAL(sigWidget()),obj,SIGNAL(widgetClicked()));

    quickWidget->setLayout(layout);
    quickWidget->show();
}
void QmlWidget::slotWidget() {
    qDebug()<<"qml sig to widget slot";
    emit sigWidget();
}
void QmlWidget::btnClicked() {
    qDebug()<<"widget btn clicked";
}

5、main.qml如下

import QtQuick 2.4
import QtQuick.Layouts 1.2
import QtQuick.Controls 1.4
import QtQuick.Dialogs 1.2

Rectangle {
    id : root;
     300
    height: 300
    color: "yellow"
    signal qmlClicked()
    signal widgetClicked()
    onWidgetClicked: {
        console.log("widget sig to qml slot")
    }
    Button {
        id : qmlBtn
        anchors.top: parent.top
        text : "qml btn"
        onClicked: {
            console.log("qml btn clicked")
        }
    }
    Button {
        anchors.left: qmlBtn.right
        anchors.leftMargin: 8
        text : "connect btn"
        onClicked: {
            qmlClicked()
        }
    }
}

6、运行效果如下

7、注意事项。

quickWidget的rootObject()是main.qml中的根对象,也就是root,它要转换为QObject*类型才能使用connect。

quickWidget不能直接连接到qml的槽上,但是可以连接到qml的信号上,让信号去触发qml的槽。

原文地址:https://www.cnblogs.com/lvdongjie/p/13536603.html