Signals in QML Repeater

[Aleksun]

I have a unit

SomeUnit {
           x: 1
           y: 2
           width: 10
           height: 15
           unitId: "sensor#0"
        }

inherited from Item (It's rectangle)
And I need create some units.
If I create it handly:

SomeUnit { ... }
SomeUnit { ... }

my macro

Q_PROPERTY(QString unitId READ unitId WRITE setUnitId NOTIFY unitIdChanged)

works correctly.
If I use Repeater with Grid :

Grid {
                       ...
                Repeater {
                    model: 50
                    SomeUnit {
                        width: 10
                        height: 15
                        unitId: "sensor#" + (index - 1)
                    }
                }
            }

macros doesn't work.
Any cases?