real ruler on iOS and android

zenghsing

In fact, I want to try to zoom-in and zoom-out my screen.

But my first thing it to set the real size on my screen for each object.

Hence, I want to put a ruler to measure my each object on my app.

My first thing is to know how to set the ratio for each object length.

I find some document, but I still have no idea.

        console.log("Screen.pixelDensity : "+Screen.pixelDensity)
        console.log("Screen.devicePixelRatio : "+Screen.devicePixelRatio)

How to translate to my real scale? How to get the ratio?

What function could I use in QML and widgets ?