How to acess a subobject of dynamically created object

[anuj87_]

Hi,
I have a qml file called gasgroup.qml as below:
Rectangle{
id:gasgroup
Row{
id:row
}
Column{
id:col
}
}

I then create a object from this qml dynamically
var gasobject = GasComponent.createobject(gasgrouop.qml);

i want to access the rowobject(row) inside the gasgroup.qml from this dynamic object
gasobject.Can someone explain how can i do so ?

[sierdzio]

Please use code tags around your code, it makes it much easier to read.

i want to access the rowobject(row) inside the gasgroup.qml from this dynamic object gasobject.Can someone explain how can i do so ?

There are a few ways to do it:

• add an alias property in gasgroup pointing to your subobject. Then you can easily access it using gasobject.yourAliasProp
• name the subobject (objectName property), then use QObject's findChild() method
• use children property: gasobject.children[0]

The alias property is by far the most elegant option.

[anuj87_]

@sierdzio said in How to acess a subobject of dynamically created object:

meth
Thanks for replying!
I tries the property alias way by adding the below line to my "gasgroup.qml"
"property alias row: row".
I have a seperate JS file from which I am first creating a "gasgroupcomponent"
and then using createobject() to create the object.

Even after adding property alias in qml file still I am getting the below error:
qrc:/GasGroupBuilder.js:112: TypeError: Cannot read property 'row' of undefined

[sierdzio]

@anuj87_ said in How to acess a subobject of dynamically created object:

Cannot read property 'row' of undefined

That means that your object is undefined. So your gasobject is not set / created properly.

[anuj87_]

@sierdzio said in How to acess a subobject of dynamically created object:

name the subobject (objectName property), then use QObject's findChild() method
is findChild() object method accessible from JS. I did it this way.
Example:
GasGroupComponent = Qt.createComponent("GasGroup.qml")
gasGroupObject = GasGroupComponent .createObject(parent);
var rowobject = gasGroupObject.findChild("rowest");
if(rowobject !== null)
console.log("Row object found in GasGroup Object");
}

But I am getting this error
"qrc:/GasGroupBuilder.js:52: TypeError: Property 'findChild' of object GasGroup_QMLTYPE_0(0x2d51d840) is not a function"

gasGroup Object is getting created as i am able to see all the visual component after object creation.

[Yashpal]

@anuj87_ The findChild() is not exposed for an Item in QML. So, you won't able to call an non-existence function from QML. It's a method available for an TYPE QObject object in Qt.

[anuj87_]

@Yashpal Thanks for you reply
So can i accomplish the above task in qml by other means i.e
Creating a object dynamically and then retrieve a subobject from the dynamic object .

[Yashpal]

@anuj87_ @sierdzio has mentioned the solutions. Please try using aliasing or use children property of parent item to get things done.

[anuj87_]

Thanks sierdzio and yashpal
With your valuabl input I am able for create a soulution by adding a method "findchild( object_name)" inside gasgroup.qml
function findchildObject( object_name)
{
for( var i =0 ; i<gasgroup.children.length; i++)
{
if(gasgroup.children[i].objectName === object_name)
return gasgroup.children[i];
}
return null;
}

I am able to get the childobjcet now by using the children and objectName property.

Thanks