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What is the use of static constructors?
... required configuration data into readonly fields, etc.
It is run automatically by the runtime the first time it is needed (the exact rules there are complicated (see "beforefieldinit"), and changed subtly between CLR2 and CLR4). Unless you abuse reflection, it is guaranteed to run at most once (ev...
Update ViewPager dynamically?
... solution is to override getItemPosition(). When notifyDataSetChanged() is called, ViewPager calls getItemPosition() on all the items in its adapter to see whether they need to be moved to a different position or removed.
By default, getItemPosition() returns POSITION_UNCHANGED, which means, "This...
How to call shell commands from Ruby
How do I call shell commands from inside of a Ruby program? How do I then get output from these commands back into Ruby?
20...
JavaScript % (modulo) gives a negative result for negative numbers
...
I don't know that I would call it a "bug". The modulo operation is not very well defined over negative numbers, and different computing environments handle it differently. Wikipedia's article on the modulo operation covers it pretty well.
...
Why does ASP.NET webforms need the Runat=“Server” attribute?
....
It continues:
If <runat=client> was required for all client-side tags, the parser would need to parse all tags and strip out the <runat=client> part.
He continues:
Currently,
If my guess is correct, the parser
simply ignores all text (tags or no
tags) unless it is a...
Hiding textarea resize handle in Safari
...
You can override the resize behaviour with CSS:
textarea
{
resize: none;
}
or just simply
<textarea style="resize: none;">TEXT TEXT TEXT</textarea>
Valid properties are: both, horizontal, vertical, none
...
List of ANSI color escape sequences
...osition of trying to remember what colours are what, I have a handy script called: ~/bin/ansi_colours:
#!/usr/bin/python
print "\\033[XXm"
for i in range(30,37+1):
print "\033[%dm%d\t\t\033[%dm%d" % (i,i,i+60,i+60);
print "\033[39m\\033[39m - Reset colour"
print "\\033[2K - Clear Line"
print ...
When should I use the new keyword in C++?
... above constraints.
Some easy cases:
If you don't want to worry about calling delete, (and the potential to cause memory leaks) you shouldn't use new.
If you'd like to return a pointer to your object from a function, you must use new
...
Finish an activity from another activity
...ingleInstance"
When the user clicks new, do FirstActivity.fa.finish(); and call the new Intent.
When the user clicks modify, call the new Intent or simply finish activity B.
FIRST WAY
In your first activity, declare one Activity object like this,
public static Activity fa;
onCreate()
{
fa = ...
What do helper and helper_method do?
...pplication_controller.rb
def current_user
@current_user ||= User.find_by_id!(session[:user_id])
end
helper_method :current_user
the helper method on the other hand, is for importing an entire helper to the views provided by the controller (and it's inherited controllers). What this means is doin...