Example ToolbarButton.py

Import system modules used in this example. The regular expression module, re, is used for matching atom names. The operating system module, os, is used for constructing the icon file name (see below).
import re
import os


Import Chimera modules used in this example. The chimera module is needed to access the molecular data.
import chimera


Function mainchain sets the display status of atoms and requires no arguments. The body of the function is identical to the example described in Molecular Editing Using Python.
def mainchain():


MAINCHAIN = re.compile("^(N|CA|C)$", re.I)
for m in chimera.openModels.list(modelTypes=[chimera.Molecule]):


for a in m.atoms:


a.display = MAINCHAIN.match(a.name) != None


Create a button in the toolbar. The first argument to chimera.tkgui.app.toolbar.add is the icon, which is either the path to an image file, or the name of a standard Chimera icon (which is the base name of an image file found in the "share/chimera/images" directory in the Chimera installation directory). In this case, since ToolbarButton.tiff is not an absolute path, the icon will be looked for under that name in both the current directory and in the Chimera images directory. The second argument is the Python function to be called when the button is pressed (a.k.a., the "callback function"). The third argument is a short description of what the button does (used typically as balloon help). The fourth argument is the URL to a full description. For this example the icon name is ToolbarButton.tiff; the Python function is mainchain; the short description is "Show Main Chain"; and there is no URL for context help.
chimera.tkgui.app.toolbar.add('ToolbarButton.tiff', mainchain, 'Show Main Chain', None)