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How to pull a random record using Django's ORM?
...['count']
random_index = randint(0, count - 1)
return self.all()[random_index]
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How to get object length [duplicate]
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This is actually worse than using a simple loop and counter because of the added overhead of the callback function.
– nullability
Feb 19 '13 at 17:35
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Proper use of beginBackgroundTaskWithExpirationHandler
...l need to wrap it in a background task. It's also very important that you call endBackgroundTask when you're finished - otherwise the app will be killed after its allotted time has expired.
Mine tend look something like this:
- (void) doUpdate
{
dispatch_async(dispatch_get_global_queue(DISPAT...
Making a property deserialize but not serialize with json.net
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There are actually several fairly simple approaches you can use to achieve the result you want.
Let's assume, for example, that you have your classes currently defined like this:
class Config
{
public Fizz ObsoleteSetting { get; set;...
Swift Programming: getter/setter in stored property
...the new value that you assign will replace the one that was just set.
So all you have to do is this:
var rank: Int = 0 {
didSet {
// Say 1000 is not good for you and 999 is the maximum you want to be stored there
if rank >= 1000 {
rank = 999
}
}
}
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Can I have onScrollListener for a ScrollView?
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Every instance of View calls getViewTreeObserver(). Now when holding an instance of ViewTreeObserver, you can add an OnScrollChangedListener() to it using the method addOnScrollChangedListener().
You can see more information about this class here.
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Deadly CORS when http://localhost is the origin
...lija's comment is correct, adding these headers to localhost will not magically give you access to all other sites. It's the remote site that needs to be served with these headers.
– Rob W
Mar 22 '14 at 22:59
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Getting visitors country from their IP
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why im getting unknow all the time with every ip ? , used same code.
– echo_Me
Feb 18 '14 at 18:12
1
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When are you supposed to use escape instead of encodeURI / encodeURIComponent?
... section B.2.1.2 escape and the introduction text of Annex B says:
... All of the language features and behaviours specified in this annex have one or more undesirable characteristics and in the absence of legacy usage would be removed from this specification. ...
... Programmers should not us...
Case objects vs Enumerations in Scala
... deal with an Option[Currency] type that would clearly indicate there is really a matching problem and "encourage" the user of the API to sort it out him/herself.
To follow up on the other answers here, the main drawbacks of case objects over Enumerations are:
Can't iterate over all instances of t...