Difference between revisions of "Development Team/Almanac"
Line 70: | Line 70: | ||
=== How do I know whether my activity is running on a physical XO? === | === How do I know whether my activity is running on a physical XO? === | ||
While your activity is typically going to be run on a real XO, there might be circumstances (such as for development through sugar-jhbuild) that you will not be running on an XO machine. The easiest way to tell if you are on a physical XO is to check whether /sys/power/olpc-pm, an essential power management file for the XO, exists. <ref>[http://lists.laptop.org/pipermail/devel/2008-June/015923.html reliably detecting if running on an XO]</ref> <ref>[http://wiki.laptop.org/go/Power_Management_Interface OLPC Power Management Interface]</ref> | While your activity is typically going to be run on a real XO, there might be circumstances (such as for development through sugar-jhbuild) that you will not be running on an XO machine. The easiest way to tell if you are on a physical XO is to check whether /sys/power/olpc-pm, an essential power management file for the XO, exists. <ref>[http://lists.laptop.org/pipermail/devel/2008-June/015923.html reliably detecting if running on an XO]</ref> <ref>[http://wiki.laptop.org/go/Power_Management_Interface OLPC Power Management Interface]</ref> | ||
+ | |||
+ | |||
+ | <pre> | ||
+ | import os | ||
+ | ... | ||
+ | #Print out a boolean value that tells us whether we are on an XO or not. | ||
+ | print os.path.exists('/sys/power/olpc-pm') | ||
+ | </pre> | ||
= Notes = | = Notes = | ||
<references /> | <references /> |
Revision as of 15:23, 9 July 2008
How do I get additional help beyond this almanac?
- Looking to get started with the basics of sugar development? Check out Christoph Derndorfer's Activity Handbook.
- See also Sugar Code Snippets
Now, on to the actual almanac ...
Package: sugar
Package: sugar.activity
Package: sugar.datastore
Package: sugar.graphics
Logging
- sugar.logger
- Notes on using Python Standard Logging in Sugar
Internationalization
MISCELLANEOUS
The tasks below are random useful techniques that have come up as I write code and documentation for this reference. They have yet to be categorized, but will be as a sufficient set of related entries are written.
How do I know when my activity is "active" or not?
You can set an event using the VISIBILITY_NOTIFY_MASK constant in order to know when your activity changes visibility. Then in the callback for this event, you simply compare the event's state to gtk-defined variables for activity visibility. See the GDK Visibility State Constants section of gtk.gdk.Constants for more information.
#Notify when the visibility state changes by calling self._visibleNotifyCb #(PUT THIS IN YOUR ACTIVITY CODE - EG. THE __init__() METHOD) self.add_events(gtk.gdk.VISIBILITY_NOTIFY_MASK) self.connect("visibility-notify-event", self._visibleNotifyCb) ... #Callback method for when the activity's visibility changes def _visibleNotifyCb(self, widget, event): if (event.state == gtk.gdk.VISIBILITY_FULLY_OBSCURED): print "I am not visible" elif (event.state == gtk.gdk.VISIBILITY_UNOBSCURED): print "I am visible"
How do I get the amount of free space available on disk under the /home directory tree?
The following function uses the statvfs module. The following code demonstrates how to get the total amount of free space under /home.
#### Method: getFreespaceKb, returns the available freespace in kilobytes. def getFreespaceKb(self): stat = os.statvfs("/home") freebytes = stat[statvfs.F_BSIZE] * stat[statvfs.F_BAVAIL] freekb = freebytes / 1024 return freekb
How do I know whether my activity is running on a physical XO?
While your activity is typically going to be run on a real XO, there might be circumstances (such as for development through sugar-jhbuild) that you will not be running on an XO machine. The easiest way to tell if you are on a physical XO is to check whether /sys/power/olpc-pm, an essential power management file for the XO, exists. [1] [2]
import os ... #Print out a boolean value that tells us whether we are on an XO or not. print os.path.exists('/sys/power/olpc-pm')