Hi Wim
As always, Thomas's advice is sound: a true software engineer.
Perhaps you should explain your use case in more detail: why you want
your C++ to have deep insight into the QML side.
I have always considered the QML side to be the client, and the C++
(plugin) to be the server, offering services to the QML; with the QML
being in control. But it would interest me to hear of different models.
Tot zins
Chris
Zitat von "Thomas Perl" <th.p...@gmail.com>:
Hi Wim,
On May 13, 2013, at 3:24 PM, Wim de Vries <wsvr...@xs4all.nl> wrote:
I am setting up the default Sailfish ("Hello sailors" app) project
with all kinds of QML-C++ communication.
After
object = view->rootObject("main.qml");
I get the main.qml object (created via QDeclarativeView's setSource() ).
But how can I get the other QML objects (e.g. the SecondPage.qml,
Coverpage.qml)?
findChild() only finds childs in main.qml (the one specified by
setSource()).
In 97.6% of the cases, you don't want to do that (it makes your C++
code dependent on the structure of the QML UI). The better way to
interface C++ and QML is to either write a QML Plugin in C++ and
instantiate that from the QML side, or to expose a global
"controller" object as context property to QML.
If you think your use case is one of the 2.4%, you can add a variant
property to your main object and then in QML point it to the object
you want exposed, e.g.:
Rectangle {
property variant something: someObject
Item { id: someObject }
}
You should then be able to get the "something" property from your
main object and receive a reference to the item. Of course, this
doesn't work that well when you dynamically instantiate objects, so
the plugin or context property way is still the recommended way of
doing things. Your controller object could even have a function like
this (untested):
Q_INVOKABLE void registerObject(QString name, QObject *object);
You could then let your C++ controller object know about that object
from QML like this:
Item {
id: blubb
Component.onCompleted: controller.registerObject('blubb', blubb)
}
In general, though, don't do this - the C++ side should not make any
assumptions about the structure and objects in QML. It will make the
architecture of your app nicer and easier to adapt to UI changes.
Also, it will be easier to debug, as there is a single place (the
controller object) through which communcation happens.
HTH :)
Thomas
_______________________________________________
SailfishOS.org Devel mailing list
_______________________________________________
SailfishOS.org Devel mailing list
