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