Salut Lucien

Maybe it is clearer with Code examples

I was doing this, which gives me an error, but seems to work!

Q_DECL_EXPORT int main(int argc, char *argv[])
{
QScopedPointer<QGuiApplication> app(Sailfish::createApplication(argc, argv));
    QScopedPointer<QQuickView> view(Sailfish::createView("main.qml"));
    view->rootContext()->setContextProperty("cppproperty",  "Hello world");
    Sailfish::showView(view.data());
    return app->exec();
}

You suggest I could this:

Q_DECL_EXPORT int main(int argc, char *argv[])
{
QScopedPointer<QGuiApplication> app(Sailfish::createApplication(argc, argv));
    QScopedPointer<QQuickView> view(Sailfish::createView());
    view->rootContext()->setContextProperty("cppproperty",  "Hello world");
    Sailfish::setView(view.data(), "main.qml");
    Sailfish::showView(view.data());
    return app->exec();
}

..but will then run into your template error:
file:///usr/share/setContextPropertyDemo/main.qml: File not found

Maybe the qmlRegister**Type is the best approach after all. The downside is (unless I have missed something) that I will then have to create a class for my property, whereas with the setContextProperty I can use a string literal or a primitive type like int.

Merci

Chris


Zitat von "Lucien XU" <sfietkonstan...@free.fr>:

Hello guys !

It might be useful to use qmlRegister**Type (uncreatable, singleton etc.) to
expose C++ components to QML. But if you really want to use rootContext()-
setContextProperty, you have to be cautious.

Actually, if you pass the qml file to the view before registering C++
components, the QML components won't be able to see the C++ ones, so you have
to call setContextProperty before calling setSource (or calling the
createView("main.qml") method).

You have to call the parameter-less method createView(), and then, call
setView(QQuickView *, QString) to pass the source QML file.

But beware, there is a bug in the template. See
https://lists.sailfishos.org/pipermail/devel/2013-August/000529.html.

Hopes it helps (because I'm not very clear in this mail)
Cheers,
Lucien

Le dimanche 4 août 2013 17:05:01 christopher.l...@thurweb.ch a écrit :
Hi Martin

Curiouser and Curiouser!

Just to be sure, I went back and tested your suggestion in a demo
project based on the default "Hello Sailors" new project template.

Here I pass the c++ property cppproperty with the value "Hello World".
In the QML FirstPage this is concatenated to the "Hello Sailors" label
text.

I still get this error:
file:///opt/sdk/setContextPropertyDemo/usr/share/setContextPropertyDemo/page
s/FirstPage.qml:34: ReferenceError: cppproperty is not defined

Yet the app displays "Hello Sailors: Hello world".

So a property can be passed as you suggested, it can be used. The
error must be wrong!

Chris

P.s you test the same by creating a default new Sailfish project, and
replacing the main.cpp and FirstPage.qml with the code below.


//start main.cpp
#include <QGuiApplication>
#include <QQuickView>
#include <QQmlContext>

#include "sailfishapplication.h"

Q_DECL_EXPORT int main(int argc, char *argv[])
{
     QScopedPointer<QGuiApplication>
app(Sailfish::createApplication(argc, argv));
     QScopedPointer<QQuickView> view(Sailfish::createView("main.qml"));
     view->rootContext()->setContextProperty("cppproperty",  "Hello world");
Sailfish::showView(view.data());

     return app->exec();
}
//end main.cpp


//start FirstPage.qml
import QtQuick 2.0
import Sailfish.Silica 1.0
import Sailfish.Silica.theme 1.0


Page {
     id: page

     // To enable PullDownMenu, place our content in a SilicaFlickable
     SilicaFlickable {
         anchors.fill: parent

         // PullDownMenu and PushUpMenu must be declared in
SilicaFlickable, SilicaListView or SilicaGridView
         PullDownMenu {
             MenuItem {
                 text: "Show Page 2"
                 onClicked: pageStack.push(Qt.resolvedUrl("SecondPage.qml"))
}
         }

         // Tell SilicaFlickable the height of its content.
         contentHeight: childrenRect.height

         // Place our content in a Column.  The PageHeader is always
placed at the top
         // of the page, followed by our content.
         Column {
             width: page.width
             spacing: Theme.paddingLarge
             PageHeader {
                 title: "UI Template"
             }
             Label {
                 x: Theme.paddingLarge
                 text: "Hello Sailors: " + cppproperty
                 color: Theme.secondaryHighlightColor
                 font.pixelSize: Theme.fontSizeLarge
             }
         }
     }
}
//end FirstPage.qml

Zitat von "Martin Grimme" <martin.gri...@gmail.com>:
> Hi,
>
> you don't want to set the context property on the
> QmlApplicationViewer, which was dead Nokia code to target Symbian and
> Harmattan, anyway.
> QmlApplicationViewer was derived from QmlView, where it got the
> rootContext() method from.
>
> With Qt5, QmlView was renamed to QQuickView. And when using the
>
> functions from sailfishapplication.h, you get a QQuickView*, e.g.:
>         QScopedPointer<QQuickView> view(Sailfish::createView("main.qml"));
>         view->rootContext()->setContextProperty("platform", platformId);
>
> Martin
>
> 2013/8/4, christopher.l...@thurweb.ch <christopher.l...@thurweb.ch>:
>> Hi all
>>
>> What is the recommended way to pass simple c++ properties from the
>> main.cpp to the QML part of a project using the Qt 5 Alpha?
>>
>> In the good old days of the first Alpha, I used to do this Harmattan
>> style using
>>
>>      QmlApplicationViewer viewer;
>>      viewer.rootContext()->setContextProperty("platform",  platformId);
>>
>> This would make the c++ property platformId available to my qml code
>> as the property platform.
>>
>> Now with Qt5 / Alpha 2 the QmlApplicationViewer is no longer created.
>>
>> The tutorial linked below suggests that the QmlApplicationViewer files
>> could be ported to Qt5, so I guess I could grab these files from an
>> old Harmattan project and do that.
>>
>> https://qt-project.org/doc/qt-5.0/qtdoc/portingqmlapp.html
>>
>> But somehow that feels like carting old baggage around.
>>
>> Is their a Sailfish native way of doing the same?
>>
>> Thanks
>>
>> Chris
>>
>>
>>
>>
>> _______________________________________________
>> SailfishOS.org Devel mailing list

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