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Why do std::shared_ptr work
I found some code using std::shared_ptr to perform arbitrary cleanup at shutdown. At first I thought this code could not possibly work, but then I tried the following:
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UIButton inside a view that has a UITapGestureRecognizer
I have view with a UITapGestureRecognizer . So when I tap on the view another view appears above this view. This new view has three buttons. When I now press on one of these buttons I don't get the buttons action, I only get the tap gesture action. So I'm not able to use these buttons anymore. What...
“unrecognized selector sent to instance” error in Objective-C
I created a button and added an action for it, but as soon as it invoked, I got this error:
38 Answers
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Why doesn't Python have a sign function?
I can't understand why Python doesn't have a sign function. It has an abs builtin (which I consider sign 's sister), but no sign .
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How to hide soft keyboard on android after clicking outside EditText?
...ippet simply hides the keyboard:
public static void hideSoftKeyboard(Activity activity) {
InputMethodManager inputMethodManager =
(InputMethodManager) activity.getSystemService(
Activity.INPUT_METHOD_SERVICE);
inputMethodManager.hideSoftInputFromWindow(
activity...
Why is address zero used for the null pointer?
...: I am adviced to set pointers to zero after freeing their memory, because it means freeing the pointer again isn't dangerous; when I call malloc it returns a pointer with the value zero if it can't get me memory; I use if (p != 0) all the time to make sure passed pointers are valid, etc.
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Correct format specifier to print pointer or address?
...6.1 ¶8.)
On some platforms, that will include a leading 0x and on others it won't, and the letters could be in lower-case or upper-case, and the C standard doesn't even define that it shall be hexadecimal output though I know of no implementation where it is not.
It is somewhat open to debate whe...
Concept of void pointer in C programming
Is it possible to dereference a void pointer without type-casting in the C programming language?
15 Answers
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What is in your Mathematica tool bag? [closed]
We all know that Mathematica is great, but it also often lacks critical functionality. What kind of external packages / tools / resources do you use with Mathematica?
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JavaScript get clipboard data on paste event (Cross browser)
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The situation has changed since writing this answer: now that Firefox has added support in version 22, all major browsers now support accessing the clipboard data in a paste event. See Nico Burns's answer for an example.
In the p...