Text Animation

[Fazer]

Hello,

I was wondering if anyone has done any simple text-based animation?

I mean things such as text-based pre-loaders. One example would be
when you use the *nix utility called `wget.` You get that fancy "
====> " type of animation as you download a large file. Or maybe even
a rotating " | " that I have seen before in some installation
programs.

Any ideas how these effects can be achieved?

Thanks a lot!

Faizan

[Josiah Carlson]

Fazer wrote:

Hello,

I was wondering if anyone has done any simple text-based animation?

I mean things such as text-based pre-loaders. One example would be
when you use the *nix utility called `wget.` You get that fancy "
====> " type of animation as you download a large file. Or maybe even
a rotating " | " that I have seen before in some installation
programs.

Any ideas how these effects can be achieved?

Thanks a lot!

Faizan

Yeah, don't print linefeed ('\n') characters, only print carriage
returns ('\r').

import time
for i in xrange(75):
print '*'*i, '\r',
time.sleep(.1)

- Josiah

[Gordon Airport]

Fazer wrote:

snip

Or maybe even
a rotating " | " that I have seen before in some installation
programs.

On each loop use the \b backspace character to move the cursor back,
then overwrite with progressive characters for the spinner. This can
look bad if the cursor is visible.

[Skip Montanaro]

faizan> Any ideas how these effects can be achieved?

You can start here:

http://www.musi-cal.com/~skip/python/progress.py

That module provides a couple simple progress counters.

Skip

[Andrew Henshaw]

Fazer wrote:

Hello,

I was wondering if anyone has done any simple text-based animation?

I mean things such as text-based pre-loaders. One example would be
when you use the *nix utility called `wget.` You get that fancy "
====> " type of animation as you download a large file. Or maybe even
a rotating " | " that I have seen before in some installation
programs.

Any ideas how these effects can be achieved?

Thanks a lot!

Faizan

I use this:

###################################
import sys

class Spinner:
SYMBOLS = '|/-\\'
def __init__(self):
self.index = 0

def __call__(self):
sys.stdout.write(Spinner.SYMBOLS[self.index]+'\b')
self.index = (self.index+1) % len(Spinner.SYMBOLS)

###################################

And call it like this:

###################################
if __name__ == '__main__':
import time

spin = Spinner()
for i in range(100):
spin()
time.sleep(0.1)
###################################
This looks fine under the Win2K cmd window; but, as pointed out in another
reply, you may need to turn off the cursor. I just tested it under Konsole
on Linux, and the block cursor doesn't allow the effect to show.

--Andy