1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
|
###############################################################################
#
# file: dot.py
#
# Purpose: refer to python doc for documentation details.
#
# Note: This file is part of Termsaver application, and should not be used
# or executed separately.
#
###############################################################################
#
# Copyright 2012 Termsaver
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
#
###############################################################################
"""
This module contains a simple screen that displays a running dot on terminal.
See additional information in the class itself.
The screen class available here is:
* `DotScreen`
"""
#
# Python mobdules
#
import random
import time
#
# Internal modules
#
from termsaverlib.screen.base import ScreenBase
from termsaverlib.screen.helper.position import PositionHelperBase
from termsaverlib import constants, exception
from termsaverlib.i18n import _
class DotScreen(ScreenBase, PositionHelperBase):
"""
Simple screen that displays a running (animation) dot on a terminal window.
From its base classes, the functionality provided here bases on the
settings defined below:
* clean up each cycle: True
this will force the screen to be cleaned (cleared) before each new
cycle is displayed
"""
def __init__(self):
"""
The constructor of this class.
"""
ScreenBase.__init__(self,
"dot",
_("displays a random running dot"),
{'opts': 'hc:d:', 'long_opts': ['help', 'char=', 'delay=']},
)
self.char = "*"
self.text = ""
self.size = 1
self.delay = 0.05
self.cleanup_per_cycle = True
def _run_cycle(self):
"""
Executes a cycle of this screen.
"""
# calculate random position based on screen size
self.get_terminal_size()
if len(self.text) == 0:
self.text = self.char
if self.pos_x in (self.screen_width - len(self.text),
self.screen_width):
self.pos_x = 1
self.pos_y = random.randint(1, self.screen_height)
# change char size randomly
if (len(self.text) > 1 or len(self.text) == self.screen_width) \
and random.random() < 0.5:
self.text = self.text[:-1] # remove trailing char
else:
self.text += self.char # add char
self.pos_x += 1
txt = "\n" * self.pos_y + " " * self.pos_x + self.text \
+ " " * (self.screen_width - self.pos_x - len(self.text))
# just print the whole text
print txt
time.sleep(self.delay)
def _usage_options_example(self):
"""
Describe here the options and examples of this screen.
The method `_parse_args` will be handling the parsing of the options
documented here.
Additionally, this is dependent on the values exposed in `cli_opts`,
passed to this class during its instantiation. Only values properly
configured there will be accepted here.
"""
print _("""
Options:
-c, --char Sets the character to be showing up
default is X
-d, --delay Sets the speed of the displaying characters
default is 0.05 of a second (advised to keep
between 0.1 and 0.01).
-h, --help Displays this help message
Example:
$ %(app_name)s %(screen)s
This will trigger the screensaver to display a dot on screen, with random
size increase.
$ %(app_name)s %(screen)s -c +
Overrides the default dot (.) character to be a plus sign (+)
""") % {
'app_name': constants.App.NAME,
'screen': self.name,
}
def _parse_args(self, prepared_args):
"""
Handles the special command-line arguments available for this screen.
Although this is a base screen, having these options prepared here
can save coding for screens that will not change the default options.
See `_usage_options_example` method for documentation on each of the
options being parsed here.
Additionally, this is dependent on the values exposed in `cli_opts`,
passed to this class during its instantiation. Only values properly
configured there will be accepted here.
"""
for o, a in prepared_args[0]: # optlist, args
if o in ("-h", "--help"):
self.usage()
self.screen_exit()
elif o in ("-d", "--delay"):
try:
# make sure argument is a valid value (float)
self.delay = float(a)
except:
raise exception.InvalidOptionException("delay")
elif o in ("-c", "--char"):
# make sure argument is a valid value (single char)
if len(a) != 1:
raise exception.InvalidOptionException("char")
else:
self.char = a
else:
# this should never happen!
raise Exception(_("Unhandled option. See --help for details."))
|
