How to get the current layer used in the GUI ?

alto

I am trying to code a simple script that detect what is the active layer in the menu
and use it to draw some polygon. (in this case it should be POLY1 )

I thought I can find something inside 'current_view()'

pya.Application.instance().main_window().current_view()

it seems I cannot find anything useful at this level

I tried to examine the content of

pya.Application.instance().main_window().current_view().begin_layers()

(with this simple script, that print some property of the layer, like : valid,.visible ...)

print("\n\nbegin_layers")
ap=pya.Application.instance().main_window().current_view().begin_layers()
while not ap.at_end() :
cur=ap.current()
print(cur)
print(cur.name,cur.valid,cur.visible)
ap.next()

Still nothing is telling what is the current active layer in the gui (may is there but I do not know how to access)
I also trying a "promising" LayerInfo(), pya.LayerInfo(), apparently intuition does not help.
I am on the wrong track...

Matthias

Why not trying the obvious? It's called "LayoutView#current_layer" ...

Matthias

alto

I tried the obvious but I found not to be so obvious in python .... due to the switch between iterators and method.
The first issue was to answer the question: can this be done ?

I could not get it working in python, some doubts start emerging.

So, I had to learn basic ruby (methods inspection, sorting, etc )

In ruby it was more obvious. Actually, the syntax was more coherent than python

          #print the layer selected in the menu
            layout_view = RBA::Application::instance.main_window.current_view
            puts layout_view.current_layer.current.name =>  I got 'I2  13  0 POLY1 d'

At this point I knew it was possible ...

Python:
1. import pya
2. layout_view=pya.Application.instance().main_window().current_view()
3. the obvious was
4. layout_view.current_layer().current().name
5. Nope ! tried various combination with/without () nothing work.
6.
7. layout_view.current_layer() => TypeError: 'LayerPropertiesIterator' object is not callable
8. layout_view.current_layer => ok
9. layout_view.current_layer.current.name => AttributeError: 'builtin_function_or_method'
10. layout_view.current_layer.current() => ok
11. layout_view.current_layer.current().name => finally I got 'I2 13 0 POLY1 d'

At the end 3 lines of code:

          import pya  
          layout_view=pya.Application.instance().main_window().current_view()
          print(layout_view.current_layer.current().name)

I got stuck on 4 and all variants because I was expecting "current_layer" to be a
method returning a list or something similar.
In spite

            dir(layout_view.current_layer) 

is telling me otherwise, the error also is saying 'LayerPropertiesIterator'

A classic example of seeing what you want, not what it is ...

Eventually I figure out.

I am used to cadence skill language, I have hard time to think in term of classes and iterator,
in skill almost everything is a list ...

Thanks anyway.

alto

AI also failed

https://claude.ai
query:
by using https://www.klayout.de/doc-qt5/programming/index.html can you find how to write a script in python that identify what layer is selected in the gui ?

This is the code generated. It does not work !
It is partially correct.

 import pya  # pya is KLayout's Python module (equivalent of RBA in Ruby)

  # Get the current layout view
 view = pya.LayoutView.current()

  if view is None:
     print("No layout is open.")
  else:
  # Get an iterator to the currently focused layer (the one with the focus frame)
  current_layer_iter = view.current_layer()

   if current_layer_iter.is_null():
      print("No layer is currently selected.")
   else:
      props = current_layer_iter.current()  # LayerPropertiesNodeRef object
      layer_info = props.source            # e.g. "1/0" or "Metal1"
      layer_num  = props.source_layer      # integer layer number
      datatype   = props.source_datatype   # integer datatype
      name       = props.name              # display name (if set)

      print(f"Current layer : {layer_info}")
      print(f"  Layer number: {layer_num}")
      print(f"  Datatype    : {datatype}")
      print(f"  Name        : {name}")

Matthias

Man, how I hate substituting for AI ...

If you read the documentation of "LayoutView#current_layer" here: https://www.klayout.de/doc-qt5/code/class_LayoutView.html#method70 - it gives you a valuable hint:

Python specific notes:
The object exposes a readable attribute 'current_layer'. This is the getter.

That means, it's a property, not a method. No brackets needed.

And if you fix the broken indentation of your code like this:

import pya  # pya is KLayout's Python module (equivalent of RBA in Ruby)

# Get the current layout view
view = pya.LayoutView.current()

if view is None:
  print("No layout is open.")
else:
  # Get an iterator to the currently focused layer (the one with the focus frame)
  current_layer_iter = view.current_layer

  if current_layer_iter.is_null():
    print("No layer is currently selected.")
  else:
    props = current_layer_iter.current()  # LayerPropertiesNodeRef object
    layer_info = props.source            # e.g. "1/0" or "Metal1"
    layer_num  = props.source_layer      # integer layer number
    datatype   = props.source_datatype   # integer datatype
    name       = props.name              # display name (if set)

    print(f"Current layer : {layer_info}")
    print(f"  Layer number: {layer_num}")
    print(f"  Datatype    : {datatype}")
    print(f"  Name        : {name}")

it works.

alto

Sorry but I never heard about getter/setter. I end up reading this after your comment.
https://realpython.com/python-getter-setter/#what-are-getter-and-setter-methods
I am an analog designer, getter/setter, properties and decorations, not my bread and butter
tools ...