how we can reset main.qml and automate it start when i clicked on text type in qml

stackprogramer

hi,we have a main.qml,i designed a text type in it,that has a text value:"reset me"
how we can reset main.qml and automate it start when i clicked on text type in main.qml

Text{
text:"reset me";
MouseArea{onClicked:{
//here whats method we use
}

}
}

whats method should i use??thanks for reply.

Charby

Could you please provide more explanations about what would you like to do when the text is clicked ?

By design, MouseArea areas are not binded with the parent area so in your sample code, don't forget to define the geometry of the MouseArea :

Text{
    text:"reset me";
    MouseArea{
         anchors.fill: parent
         onClicked:{
          //do whatever you like
          }
    }
}

stackprogramer

@Charby said:

Could you please provide more explanations about what would you like to do when the text is clicked ?

By design, MouseArea areas are not binded with the parent area so in your sample code, don't forget to define the geometry of the MouseArea :
Text{
    text:"reset me";
    MouseArea{
         anchors.fill: parent
         onClicked:{
          //do whatever you like
          }
    }
}

but i know these rules,when i clicked on the text i want to file qml that is running now ,is stoped and exited and automate it is start my former qml file again.

Charby

Actually, it depends of the purpose and the creation method of the Qml engine :

if you use a QQMLApplication you should close it, clear the components cache and call load again
If you are using a QuickView, you first clear the components cache and call setSource again
if you want to reload from QML, which is the most likely your goal, the easiest is to use a Loader element to (re)load your QML - thus the engine or view won't be reseted...

You can find here a nice presentation of the 2 first option

stackprogramer

@Charby said:

if you want to reload from QML, which is the most likely your goal, the easiest is to use a Loader element to (re)load your QML - thus the engine or view won't be reseted...

thanks for reply
when i reloaded the file.qml again,the file qml former is open and we have 2 file.qml
i want to the former qml file is closed before the new file.qml start.

Charby

Here is a short example showing method 1 and 3.

QReseter.h

#ifndef QRESETER_H
#define QRESETER_H
#include <QObject>
#include <QQmlApplicationEngine>

class QReseter : public QObject
{
    Q_OBJECT
public:
    explicit QReseter(QQmlApplicationEngine* engine);
    virtual ~QReseter();
    Q_INVOKABLE void reset();
private:
    QQmlApplicationEngine* m_pEngine = nullptr;
};
#endif // QRESETER_H

qreset.cpp

#include "qreseter.h"

QReseter::QReseter(QQmlApplicationEngine* engine)
{
    m_pEngine = engine;

}

QReseter::~QReseter()
{

}

void QReseter::reset()
{
    if (m_pEngine){

        m_pEngine->clearComponentCache();
        m_pEngine->load(QUrl(QStringLiteral("qrc:/main.qml")));
    }
}

main.cpp

#include <QGuiApplication>
#include <QQmlApplicationEngine>
#include <QQmlContext>
#include "qreseter.h"

int main(int argc, char *argv[])
{
    QGuiApplication app(argc, argv);

    QQmlApplicationEngine engine;
    QReseter reseter(&engine);
    engine.rootContext()->setContextProperty("reseter", &reseter);
    engine.load(QUrl(QStringLiteral("qrc:/main.qml")));

    return app.exec();
}

and finally the QML, main.qml

import QtQuick 2.4
import QtQuick.Window 2.2


Window {
    id:root
    visible: true
    width:640
    height:480

    Component{
        id:qmlToLoad
        Column{
            anchors.fill : parent

            Rectangle{
                width: 300; height : 100; color:"yellow"
                Text{
                    anchors.centerIn: parent
                    text:"reload QML - " + new Date().toTimeString()
                }
                MouseArea{
                    anchors.fill: parent
                    onClicked: {
                        console.log("reload")
                        loader.active = false;
                        loader.active = true;

                    }
                }
            }
            Rectangle{
                width: 300; height : 100;color:"orange"
                Text{
                    anchors.centerIn: parent
                    text:"reset engine- " + new Date().toTimeString()

                }
                MouseArea{
                    anchors.fill: parent
                    onClicked: {
                        root.close();
                        reseter.reset();

                    }
                }
            }

        }

    }

    Loader{
        id:loader
        anchors.fill: parent
        sourceComponent: qmlToLoad
    }

}

Charby

@stackprogramer

Yes, you need to first close the window before calling load again as shown in my example below...
As you can see, using the loader is the more straightforward option, furthermore it can ease the storing of states data outside of the loaded element.

stackprogramer

now i am sleepy ,tomorrow i will test it and i post the result here.thanks

stackprogramer

now i tested it,my conclusion is sharing here,
my object is solving my problem in qml.so i use this method.
this some my source it is not all my source

Window{id:root


.
.
.

roote.close();
pageLoader2.source = "main.qml"


}

now first root object is closed and is loaded main.qml
@Charby my problem is solved.your qml code is used for me.
thanks very much