ticker.py

# -*- coding: iso-8859-1 -*-
# ticker.py
# Progress indicator class
# Copyright 2006 Giuseppe Venturini

# This file is part of the ahkab simulator.
#
# Ahkab is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, version 2 of the License.
#
# Ahkab is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License v2
# along with ahkab.  If not, see <http://www.gnu.org/licenses/>.

"""
Implements a progress indicator.
"""

import sys

class ticker:
	"""This is a progress indicator class.
	
	If activated, you shouldn't print anything to screen before calling
	ticker.hide().

	If you wish to change the progress indicator, change self.progress to
	something else. 
	"""
	progress = ("-", "\\", "|", "/")
	_index = 0
	_step = 0
	_display = False
	increments_for_step = 1
	
	def __init__(self, increments_for_step=10):
		self.increments_for_step = increments_for_step
		
	def step(self, enable):
		"""After calling this function ticker.increments_for_step times
		the status is incremented."""
		if not enable:
			return
		if (self._index + 1) % self.increments_for_step == 0:
			if (self._step + 1) % len(self.progress) == 0:
				self._step = 0
			else:
				self._step = self._step + 1
			self._index = 0
			if self._display:
				sys.stdout.write("\b"+self.progress[self._step])
				sys.stdout.flush()
		else:
			self._index = self._index + 1
	
	def hide(self, enable):
		"""Before printing to screen, call this to hide the progress
		indicator.
		"""
		if not enable:
			return
		sys.stdout.write("\b")
		sys.stdout.flush()
		self._display = False
	
	def display(self, enable):
		"""Print to screen the progress indicator. Call hide to hide it
		again.
		"""
		if not enable:
			return
		sys.stdout.write(self.progress[self._step])
		sys.stdout.flush()
		self._display = True
		
	def reset(self):
		"""Reset to initial status. Doesn't hide it."""
		self._step = 0
		self._index = 0

if __name__ == "__main__":
	# test
	import time
	tk = ticker()
	tk.display()
	for i in range(100000):
		time.sleep(0.0001)
		tk.step()
	tk.hide()