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Differences between strong and weak in Objective-C
...eference to it. Once that is no longer the case, the object gets destroyed and your weak property will automatically get set to nil. The most frequent use cases of weak references in iOS are:
delegate properties, which are often referenced weakly to avoid retain cycles, and
subviews/controls of a ...
What is N-Tier architecture?
...er architecture in which,
the presentation, the application
processing and the data management are
logically separate processes. For
example, an application that uses
middleware to service data requests
between a user and a database employs
multi-tier architecture. The most
widesprea...
Using DISTINCT and COUNT together in a MySQL Query
... Updated the answer as it is close to become a great answer and it was syntactically incorrect.
– Rahul Tripathi
Sep 8 '14 at 10:20
...
Clang optimization levels
...dvars -loop-idiom -loop-deletion -loop-unroll -memdep -memcpyopt -sccp -demanded-bits -bdce -dse -postdomtree -adce -barrier -rpo-functionattrs -globaldce -float2int -loop-accesses -loop-distribute -loop-vectorize -loop-load-elim -alignment-from-assumptions -strip-dead-prototypes -loop-sink -instsim...
Change bootstrap navbar collapse breakpoint without using LESS
...r question, below 768px, the navbar will collapse, so apply it above 768px and below 1000px, just like that:
@media (min-width: 768px) and (max-width: 1000px) {
.collapse {
display: none !important;
}
}
This will hide the navbar collapse until the default occurrence of the bootstrap ...
Creating an Android trial application that expires after a fixed time period
... run the app save the date/time to a file, database, or shared preferences and every time you run the app after that check to see if the trial period has ended. This is easy to circumvent because uninstalling and reinstalling will allow the user to have another trial period.
The second approach is...
Why do we usually use || over |? What is the difference?
...
If you use the || and && forms, rather than the | and & forms of these operators, Java will not bother to evaluate the right-hand operand alone.
It's a matter of if you want to short-circuit the evaluation or not -- most of the ti...
How can I handle R CMD check “no visible binding for global variable” notes when my ggplot2 syntax i
... warning: aes does while aes_string doesn't define positional parameters x and y.
– topchef
Oct 18 '13 at 16:50
6
...
Python AttributeError: 'module' object has no attribute 'Serial' [duplicate]
... edited Oct 28 '18 at 15:01
Andrea Corbellini
14.6k11 gold badge3939 silver badges5656 bronze badges
answered Jul 9 '12 at 22:21
...
How do I draw a grid onto a plot in Python?
I just finished writing code to make a plot using pylab in Python and now I would like to superimpose a grid of 10x10 onto the scatter plot. How do I do that?
...