how to zoom page, like photoshop, i can put images, lables, lines…
and then i can zoom the page to fine tune the positions of elements.
Sorry, I dont really undestand. How do you mean “scale”? Does it mean zoom?
It is not easy task. If you are using v7.x.x,
I suggest you to create a second window which will always work as “lens” and will track you mouse cursor on 1st window. Then for some period just take a snapshots from some area around cursor position of the 1st screen and “zoom” it using LVGL features - link.
P.S> I never tried this solution 
but i need to change the position of widgets in the page after zoom
For me it is other task. I also thought about how to realize it. I have 2 ideas:
- Create handlers for arrow key of keyboard and modify position of the currently selected/active object
- Assign some key for switching on/off mode for changing position of the object which is under mouse cursor. When this mode is enabled (“on”) -> move position of the object. In second window area under cursor shall be updated and zoomed automatically.
… But I suppose that these solutions will have several restrictions like: auto fits, auto realignment, layout of the containers shall be disabled etc. In other words implementation of such task will be complicated too.
do you have any other idea
Directly scaling/zooming the contents of objects is not supported right now. However, as @BesitzeRuf mentioned, you can render your UI to an image and then zoom/scale the image itself.