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Your project contains error(s), please fix it before running it
I am developing a simple Android application. But when I run Eclipse, it shows the following error:
26 Answers
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Maintain the aspect ratio of a div with CSS
I want to create a div that can change its width/height as the window's width changes.
27 Answers
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What does “Memory allocated at compile time” really mean?
...ler knows at compile-time the size of the array and the size of an int, so it knows the entire size of the array at compile-time. Also a global variable has static storage duration by default: it is allocated in the static memory area of the process memory space (.data/.bss section). Given that inf...
Design by contract using assertions or exceptions? [closed]
When programming by contract a function or method first checks whether its preconditions are fulfilled, before starting to work on its responsibilities, right? The two most prominent ways to do these checks are by assert and by exception .
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Using std Namespace
There seem to be different views on using 'using' with respect to the std namespace.
15 Answers
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Should a retrieval method return 'null' or throw an exception when it can't produce the return value
...sing java language,I have a method that is supposed to return an object if it is found.
36 Answers
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What is the difference between lower bound and tight bound?
With the reference of this answer , what is Theta (tight bound)?
8 Answers
8
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performSelector may cause a leak because its selector is unknown
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Solution
The compiler is warning about this for a reason. It's very rare that this warning should simply be ignored, and it's easy to work around. Here's how:
if (!_controller) { return; }
SEL selector = NSSelectorFromString(@"someMethod");
IMP imp = [_controller methodForSelector:...
Is a Java string really immutable?
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String is immutable* but this only means you cannot change it using its public API.
What you are doing here is circumventing the normal API, using reflection. The same way, you can change the values of enums, change the lookup table used in Integer autoboxing etc.
Now, the reason ...
Explicitly calling return in a function or not
... Urbanek from the R core team (I believe) for recommending a user to explicitly calling return at the end of a function (his comment was deleted though):
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