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Detecting an undefined object property
...is the special value `undefined`");
}
To check if an object does not actually have such a property, and will therefore return undefined by default when you try and access it:
if(!o.hasOwnProperty('myProperty')) {
alert("myProperty does not exist");
}
To check if the value associated with an i...
How to lay out Views in RelativeLayout programmatically?
I'm trying to achieve the following programmatically (rather than declaratively via XML):
9 Answers
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What are the best use cases for Akka framework [closed]
...t, when I do get the OK maybe it can be added as a reference.
Akka has really pulled through on those projects, even though we started when it was on version 0.7. (we are using scala by the way)
One of the big advantages is the ease at which you can compose a system out of actors and messages wit...
Why does Apple recommend to use dispatch_once for implementing the singleton pattern under ARC?
...
dispatch_once() is absolutely synchronous. Not all GCD methods do things asynchronously (case in point, dispatch_sync() is synchronous). The use of dispatch_once() replaces the following idiom:
+ (MyClass *)sharedInstance {
static MyClass *sharedInstance;
@synchr...
Random data in Unit Tests?
...
There's a compromise. Your coworker is actually onto something, but I think he's doing it wrong. I'm not sure that totally random testing is very useful, but it's certainly not invalid.
A program (or unit) specification is a hypothesis that there exists some program ...
Catch multiple exceptions at once?
...ore lines, try to imagine if you are dealing with file IO for example, and all you want to do is catch those exceptions and do some log messaging, but only those you expect coming from your file IO methods. Then you often have to deal with a larger number (about 5 or more) different types of excepti...
window.onload vs $(document).ready()
...e HTML document has been loaded, while the onload event occurs later, when all content (e.g. images) also has been loaded.
The onload event is a standard event in the DOM, while the ready event is specific to jQuery. The purpose of the ready event is that it should occur as early as possible after ...
Can I embed a custom font in an iPhone application?
...plist, you can use your custom fonts as any other font in IB or programatically.
There is an ongoing thread on Apple Developer Forums:
https://devforums.apple.com/thread/37824 (login required)
And here's an excellent and simple 3 steps tutorial on how to achieve this (broken link removed)
Add y...
How do I find a stored procedure containing ?
... A million times what @PeteT said. This 4000 character limit really bit me a few years ago.
– Vivian River
Mar 31 '15 at 17:40
16
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Why should I capitalize my SQL keywords? [duplicate]
Simple question. I personally find a string of lowercase characters to be more readable than a string of uppercase characters. Is some old/popular flavor of SQL case-sensitive or something?
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