Drag multiple targets at once

[Fenix Voltres]

What's the best approach?

In order to do that I reparent items and map their coords, but it's painful way.
I read about QGraphicsItemGroup class, but QDeclarative Item's group setter/getter is not exposed to QML - should I do it in C++ or are there QML-ways to solve this problem?

[shullw]

I haven't tried this myself. Won't it let you set multiple drag.target: in the MouseArea?

[jimon]

just write drag proxy item, something like this :

@
MouseArea
{
id: mover; anchors.fill: parent; acceptedButtons: Qt.RightButton; drag.target = dragProxy;
}

Rectangle
{
id: testDrag1; width: 10; height:10; color:"blue"; x: 100; y:50;
}

Rectangle
{
id: testDrag2; width: 10; height:10; color:"blue"; x: 100; y:150;
}

Rectangle
{
id: dragProxy;
width: 10; height:10; color:"red"; // make me invisible

property variant dragObjects:[testDrag1, testDrag2];

property int lastX;
property int lastY;

onXChanged:
{
var deltaX = x - lastX;
for(var i = 0; i < dragObjects.length; ++i)
dragObjects[i].x += deltaX;
lastX = x;
}

onYChanged:
{
var deltaY = y - lastY;
for(var i = 0; i < dragObjects.length; ++i)
dragObjects[i].y += deltaY;
lastY = y;
}
}
@