How to push values to QML property variant two dimensional array - dynamically?

This is what I have tried:

Code:

---

import QtQuick 2.0
 
Rectangle
{
    property variant twoDimTempArray: [[]]
    property variant oneDArray: [1,2,3]
 
    MouseArea
    {
        anchors.fill: parent
        onClicked:
        {
            twoDimTempArray.push (oneDArray)
 
            twoDimTempArray[0].push (oneDArray)
 
            twoDimTempArray[0][0] = oneDArray[0]
 
            console.log (twoDimTempArray)
        }
    }
}

---

They all results in

Code:

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[]

---

.

How to push values in QML property variant two dimensional array?

What exactly are you trying to do?

Cheers,
_

I want to pass this 2 dimentional array from QML to C++ after filling some dynamically calculated values in it.

Why don't you create and calculate in C++ directly?

It seems you are trying to solve a problem that doesn't exist in a properly designed program.

Can you give a real world example instead of an abstract explanation?

Cheers,
_

Quote:

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Originally Posted by anda_skoa

Why don't you create and calculate in C++ directly?

---

This question does not make much sense to me.

I have a GUI designed in QML. User is supposed to fill in some values there.
I am supposed to calculate something from those values and then pass them to C++ so that they can be used
in an algorithm.

You think this kind of problem cannot exist in a properly designed program?

Anyways,

I have found a temporary solution as follows:

One way to add the values dynamically to a 1 dimensional QML variant is to fill a normal Javascript array and then assign it to the QML variant.

Code:

---

import QtQuick 2.0
 
Rectangle
{
    property variant oneDArray: []
    MouseArea
    {
        anchors.fill: parent
        onClicked:
        {
            var t = new Array (0)
            t.push(11)
            t.push(12)
 
            oneDArray = t
 
            console.log (oneDArray)
        }
    }
}

---

Output:

Code:

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Starting /home/.../documents/test/build-junk-Desktop_Qt_5_1_0_GCC_64bit-Debug/junk...
QML debugging is enabled. Only use this in a safe environment.
[11,12]
/home/.../documents/test/build-junk-Desktop_Qt_5_1_0_GCC_64bit-Debug/junk exited with code 0

---

Quote:

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Originally Posted by TheIndependentAquarius

This question does not make much sense to me.

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The question if you can provide a real world example?

Quote:

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Originally Posted by TheIndependentAquarius

I have a GUI designed in QML. User is supposed to fill in some values there.

---

So far so goo.

Quote:

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Originally Posted by TheIndependentAquarius

I am supposed to calculate something from those values and then pass them to C++ so that they can be used
in an algorithm.

---

Why don't you simply pass the values from the UI?
What makes it necessary to do calculations in the UI?

Quote:

---

Originally Posted by TheIndependentAquarius

You think this kind of problem cannot exist in a properly designed program?

---

No. But in a lot of cases strange requirements for QML side code are hints that the program does things in the UI context that would better be done in the application's non-UI parts.

Quote:

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Originally Posted by TheIndependentAquarius

One way to add the values dynamically to a 1 dimensional QML variant is to fill a normal Javascript array and then assign it to the QML variant.

---

Which also has the advantage of changing the value, meaning property bindings get updated.

Cheers,
_

Quote:

---

Originally Posted by anda_skoa

Why don't you simply pass the values from the UI?

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I have several points on the UI. I want the user to select some points from them.
I need to calculate the distance between the points selected by the user.
This part can be done in C++ for sure,

but I still will have to `push` the points selected by the user in a `variant` and then pass the variant to C++.
Won't I?

Depends on how you get these points in the first place.

For example if they originate in C++, e.g. as data accessed through a model, then selection could also be tracked there (state less UI).
Or the selection could be tracked in QML and passed to C++ when done.

But yes, if the values originate in QML then you'll need to pass them to C++.
Either using a C++ based property or a function call. The latter could take a list or each point individually.

Which is why I was asking for the actual use case really early.

It is usually better to find a solution to the actual problem and not to some abstract, academic one :)

Cheers,
_