Electronics

This script reads an XML BOM (also called python-bom in kicad-cli) using beautifulsoup4 and – as an usage example, generates a RefDes to footprint name dictionary:

from bs4 import BeautifulSoup

def extract_footprints_by_ref_from_xml(filename):
    footprints_by_ref = {} # e.g. "C3" => "Capacitor_SMD:C_0603_1608Metric"
    
    with open(filename, "r") as infile:
        soup = BeautifulSoup(infile, features="xml")
        
    for component in soup.export.components.findChildren("comp"):
        refdes = component.attrs["ref"]
        footprints_by_ref[refdes] = component.footprint.text
    
    return footprints_by_ref

See this doxygen link for the official API documentation.

Iterate the pads of a given pcbnew.FOOTPRINT object using

for pad in list(footprint.Pads()):
    # Example of what to do with [pad]
    print(f"{footprint.GetReference()} {pad.GetNetname()}")

Example of how to print all pads for every footprint on the board:

for footprint in list(pcbnew.GetBoard().GetFootprints()):
    for pad in list(footprint.Pads()):
        # Example of what to do with [pad]
        print(f"{footprint.GetReference()} {pad.GetNetname()}")

This will print, for example:

D1 Net-(D1-K)

Use the following for loop to iterate all footprints in the current board:

for footprint in list(pcbnew.GetBoard().GetFootprints()):
    # Example of what to do with [footprint]
    print(footprint.GetReference())

In our previous post, we showed how to get all selected objects using the KiCAD python API using

pcbnew.GetCurrentSelection()

You can simply filter these entries to obtain just a list of selected zones using either a for loop with inline filtering:

for selected_object in pcbnew.GetCurrentSelection():
    if type(selected_object).__name__ == 'ZONE':
        print(selected_object.GetReference())

or using a list comprehension:

selected_footprints: list[pcbnew.FOOTPRINT] = [
    zone for zone in pcbnew.GetCurrentSelection() if type(zone).__name__ == 'ZONE'
]

Complete plugin example:

#!/usr/bin/env python
import pcbnew
import os

class SimplePlugin(pcbnew.ActionPlugin):
    def defaults(self):
        self.name = "Plugin Name as shown in Pcbnew: Tools->External Plugins"
        self.category = "A descriptive category name"
        self.description = "A description of the plugin and what it does"
        self.show_toolbar_button = False # Optional, defaults to False
        self.icon_file_name = os.path.join(os.path.dirname(__file__), 'simple_plugin.png') # Optional, defaults to ""

    def Run(self):
        board: pcbnew.BOARD = pcbnew.GetBoard()
        footprints: list[pcbnew.FOOTPRINT] = board.GetFootprints()
        
        # TODO Do something useful with [board]
        for selected_object in pcbnew.GetCurrentSelection():
            print(selected_object)

SimplePlugin().register() # Instantiate and register to Pcbnew

Example output (excerpt):

D39
D32
D23
D37
D18
D34
D11
D15

The following python script is more or less the minimal example of a KiCAD pcbnew plugin from our previous post How to show wx dialog message in KiCAD pcbnew plugin.

#!/usr/bin/env python
import pcbnew
import wx

class DialogExamplePlugin(pcbnew.ActionPlugin):
    def defaults(self):
        self.name = "Show dialog example"
        self.category = "A descriptive category name"
        self.description = "A description of the plugin and what it does"
        self.show_toolbar_button = False # Optional, defaults to False

    def Run(self):
        dlg = wx.MessageDialog(None, "Please select one or multiple footprints!\n...or use Ctrl+A to select everything.", "No footprints selected", wx.OK | wx.ICON_ERROR)
        dlg.ShowModal()
        dlg.Destroy()

DialogExamplePlugin().register() # Instantiate and register to Pcbnew

~/.local/share/kicad/7.0/scripting/plugins/DialogExamplePlugin.py

When using KiCAD’s Python API for pcbnew, you can show a dialog by using the following snippet

# Show info dialog
dlg = wx.MessageDialog(None, "Please select one or multiple footprints!\n...or use Ctrl+A to select everything.", "No footprints selected", wx.OK | wx.ICON_ERROR)
dlg.ShowModal()
dlg.Destroy()

Note that you need to

import wx

at the top of your plugin.

This code will show the following dialog:

Complete plugin example:

#!/usr/bin/env python
import pcbnew
import wx

class DialogExamplePlugin(pcbnew.ActionPlugin):
    def defaults(self):
        self.name = "Show dialog example"
        self.category = "A descriptive category name"
        self.description = "A description of the plugin and what it does"
        self.show_toolbar_button = False # Optional, defaults to False

    def Run(self):
        dlg = wx.MessageDialog(None, "Please select one or multiple footprints!\n...or use Ctrl+A to select everything.", "No footprints selected", wx.OK | wx.ICON_ERROR)
        dlg.ShowModal()
        dlg.Destroy()

DialogExamplePlugin().register() # Instantiate and register to Pcbnew

You can place this plugin, for example, in

~/.local/share/kicad/7.0/scripting/plugins/DialogExamplePlugin.py

Don’t forget to refresh the plugins from the pcbnew menu.