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Why fragments, and when to use fragments instead of activities?
...pends on the exact fragment instance being preserved across them (by using setRetainInstance(true) on the fragment). As for layout fragments, setRetainInstance(true) doesn't make much sense, as it prevents resources associated with their views from being freed up when necessary (i.e. a memory leak)....
Why is null an object and what's the difference between null and undefined?
...ned is not an object, it's type is undefined.
You can declare a variable, set it to null, and the behavior is identical except that you'll see "null" printed out versus "undefined". You can even compare a variable that is undefined to null or vice versa, and the condition will be true:
undefined ...
SortedList, SortedDictionary and Dictionary
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Get OS-level system information
I'm currently building a Java app that could end up being run on many different platforms, but primarily variants of Solaris, Linux and Windows.
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Count rows with not empty value
In a Google Spreadsheet: How can I count the rows of a given area that have a value? All hints about this I found up to now lead to formulas that do count the rows which have a not empty content (including formula), but a cell with
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What does void* mean and how to use it?
Today when I was reading others' code, I saw something like void *func(void* i); , what does this void* mean here for the function name and for the variable type, respectively?
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How do I remove a property from a JavaScript object?
Say I create an object as follows:
46 Answers
46
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How can I access and process nested objects, arrays or JSON?
I have a nested data structure containing objects and arrays. How can I extract the information, i.e. access a specific or multiple values (or keys)?
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Does Python have “private” variables in classes?
... I don't even look at that method as the potential cause of a bad variable setting. Although it can make subsequent development of class extensions/adding features, limiting the visibility of code makes it easier to debug.
– MrMas
Nov 18 '15 at 23:01
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HTML character decoding in Objective-C / Cocoa Touch
First of all, I found this: Objective C HTML escape/unescape , but it doesn't work for me.
13 Answers
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