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Android 4.2: back stack behaviour with nested fragments
With Android 4.2, the support library got support for nested fragments see here . I've played around with it and found an interesting behaviour / bug regarding back stack and getChildFragmentManager() . When using getChildFragmentManager() and addToBackStack(String name), by pressing the back butt...
Is there documentation for the Rails column types?
...s; use these for math that needs to be accurate
See this post for examples and an in-depth explanation on the differences between floats and decimals.
Boolean:
Use to store true/false attributes (i.e. things that only have two states, like on/off)
Binary:
Use to store images, movies, and other...
C/C++ macro string concatenation
... It's more than a technicality - you can't concatenate L"a" and "b" to get L"ab", but you can concatenate L"a" and L"b" to get L"ab".
– MSalters
Mar 10 '11 at 8:59
...
JavaScript closures vs. anonymous functions
A friend of mine and I are currently discussing what is a closure in JS and what isn't. We just want to make sure we really understand it correctly.
...
Enterprise Library Unity vs Other IoC Containers [closed]
What's pros and cons of using Enterprise Library Unity vs other IoC containers (Windsor, Spring.Net, Autofac ..)?
8 Answers...
REST, HTTP DELETE and parameters
...Alex said (I don't know who downvoted him, he is correct), this should be handled in the UI, because a RESTful service as such just processes requests and should be therefore stateless (i.e. it must not rely on confirmations by holding any server-side information about of a request).
Two examples h...
Performance of static methods vs instance methods
...g to the performance characteristics of static methods vs instance methods and their scalability. Assume for this scenario that all class definitions are in a single assembly and that multiple discrete pointer types are required.
...
PostgreSQL return result set as JSON array?
...
TL;DR
SELECT json_agg(t) FROM t
for a JSON array of objects, and
SELECT
json_build_object(
'a', json_agg(t.a),
'b', json_agg(t.b)
)
FROM t
for a JSON object of arrays.
List of objects
This section describes how to generate a JSON array of objects, with eac...
Does Python have a ternary conditional operator?
...rst condition is evaluated, then exactly one of either a or b is evaluated and returned based on the Boolean value of condition. If condition evaluates to True, then a is evaluated and returned but b is ignored, or else when b is evaluated and returned but a is ignored.
This allows short-circuiting ...
How many system resources will be held for keeping 1,000,000 websocket open? [closed]
Websocket is good, but would it be able to handle 1,000,000 concurrent connections?
How many system resources will be held for keeping 1,000,000 websocket open?
...