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In Firebase, is there a way to get the number of children of a node without loading all the node dat
...way to count children without loading data, but we do plan to add it.
For now, one solution would be to maintain a counter of the number of children and update it every time you add a new child. You could use a transaction to count items, like in this code tracking upvodes:
var upvotesRef = new Fi...
Converting datetime.date to UTC timestamp in Python
...eturn (td.microseconds + (td.seconds + td.days * 86400) * 10**6) / 10**6
now = datetime.utcnow()
print now
print totimestamp(now)
Beware of floating-point issues.
Output
2012-01-08 15:34:10.022403
1326036850.02
How to convert an aware datetime object to POSIX timestamp
assert dt.tzinfo is n...
One Activity and all other Fragments [closed]
...icly available android-support-v4-googlemaps.
Ultimately most the devs I know that went the one Activity route have gone back to multiple Activities to simplify their code. UI wise, on a tablet, you are some times stuck using a single Activity just to achieve what ever crazy interaction your desig...
What's the best free C++ profiler for Windows? [closed]
... and I use PIX for Xbox 360 and found it very good, but it's not free. I know the Intel VTune , but it's not free either.
...
Is Python interpreted, or compiled, or both?
...the JVM(responsible for generating the native code for execution purpose). Now I want to show you that we call the Java as compiled language because we can see that it really compiles the source code and gives the .class file(nothing but bytecode) through:
javac Hello.java -------> produces Hel...
Nexus 7 not visible over USB via “adb devices” from Windows 7 x64
...t was only the above (changing to PTP) that enabled my Nexus 7 to show up. Now on to adding support for my apps for tablets - Thanks so much!
– Robbe
Aug 31 '12 at 18:18
6
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Force update of an Android app when a new version is available
...
@SepGH things have changed since, and Android now offers an API which you can use to force the user to upgrade and block him from continuing using the app if he doesn't upgrade to a minimum version: developer.android.com/guide/app-bundle/in-app-updates
...
What's the difference between “STL” and “C++ Standard Library”?
...long before C++ was standardised. C++ existed through the 80s, but what we now call "C++" is the language standardised in ISO/IEC 14882:2014 (and earlier versions, such as ISO/IEC 14882:2011).
The STL was already widely used as a library for C++, giving programmers access to containers, iterators a...
Update built-in vim on Mac OS X
I know this might be more appropriate at Ask Different, but as I tried adding tags there, there was no vim tag, only macvim . So I figured I might get a better audience here.
...
Git diff to show only lines that have been modified
...e lines, because the diff would not make sense without them (you couldn't know which file you were looking at, nor where you were in the file).
– Chris Hayes
Sep 15 '13 at 9:19
8
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