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When do you use Java's @Override annotation and why?
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Use it every time you override a method for two benefits. Do it so that you can take advantage of the compiler checking to make sure you actually are overriding a method when you think you are. This way, if you make a common mi...
notifyDataSetChanged example
...Application the notifyDataSetChanged() method for an ArrayAdapter but it doesn't work for me.
5 Answers
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Can you explain the concept of streams?
...tion of a sequence of bytes. Each stream provides means for reading and writing bytes to its given backing store. But what is the point of the stream? Why isn't the backing store itself what we interact with?
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What is the difference between a function expression vs declaration in JavaScript? [duplicate]
...hes that line of code.
So if you try to call a function expression before it's loaded, you'll get an error! If you call a function declaration instead, it'll always work, because no code can be called until all declarations are loaded.
Example: Function Expression
alert(foo()); // ERROR! foo was...
What does $.when.apply($, someArray) do?
...and Promises and keep coming across $.when.apply($, someArray) . I'm a little unclear on what this does exactly, looking for an explanation that one line works exactly (not the entire code snippet). Here's some context:
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Does assignment with a comma work?
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There's a lot going on here, but basically, it comes down to the comma operator.
The comma operator evaluates both of its operands (from left to right) and returns the value of the second operand.
This code:
aaa = 1,2,3
Is equivalent to:
aaa = 1;
2;
3;
So...
What is memory fragmentation?
...+ dynamic memory allocation. I've found some questions about how to deal with memory fragmentation, but can't find a direct question that deals with it itself. So:
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versionCode vs versionName in Android Manifest
I had my app in the android market with version code = 2 and version name = 1.1
10 Answers
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Check if object exists in JavaScript
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You can safely use the typeof operator on undefined variables.
If it has been assigned any value, including null, typeof will return something other than undefined. typeof always returns a string.
Therefore
if (typeof maybeObject != "undefined") {
alert("GOT THERE");
}
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SQL left join vs multiple tables on FROM line?
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The old syntax, with just listing the tables, and using the WHERE clause to specify the join criteria, is being deprecated in most modern databases.
It's not just for show, the old syntax has the possibility of being ambiguous when you use b...