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Prevent dialog dismissal on screen rotation in Android
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Create a new class which extends DialogFragment. Override onCreateDialog and return your old Dialog or an AlertDialog.
Then you can show it with DialogFragment.show(fragmentManager, tag).
Here's an example with a Listener:
public class MyDialogFragment extends DialogFragment {
public inter...
Mongo: find items that don't have a certain field
... answered Apr 19 '11 at 16:19
Andrew OrsichAndrew Orsich
47.9k1414 gold badges129129 silver badges130130 bronze badges
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Difference between array_push() and $array[] =
... as PHP has to look up the function reference, find its position in memory and execute whatever code it defines.
Using $arr[] = 'some value'; does not require a function call, and implements the addition straight into the data structure. Thus, when adding a lot of data it is a lot quicker and resou...
What is the fastest method for selecting descendant elements in jQuery?
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Method 1 and method 2 are identical with the only difference is that method 1 needs to parse the scope passed and translate it to a call to $parent.find(".child").show();.
Method 4 and Method 5 both need to parse the selector and th...
How do I auto-hide placeholder text upon focus using css or jquery?
...input type="text" placeholder="Type something here!">
Firefox 15 and IE 10+ also supports this now. To expand on Casey Chu's CSS solution:
input:focus::-webkit-input-placeholder { color:transparent; }
input:focus:-moz-placeholder { color:transparent; } /* FF 4-18 */
input:focus::-moz-plac...
How to replace all occurrences of a character in string?
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std::string doesn't contain such function but you could use stand-alone replace function from algorithm header.
#include <algorithm>
#include <string>
void some_func() {
std::string s = "example string";
std::replace( s.begin(), s.end(), 'x', 'y'); // replace all 'x' t...
What is the fastest way to compute sin and cos together?
I would like to compute both the sine and co-sine of a value together (for example to create a rotation matrix). Of course I could compute them separately one after another like a = cos(x); b = sin(x); , but I wonder if there is a faster way when needing both values.
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How do I check if an HTML element is empty using jQuery?
...empty')){
//do something
}
for more info see http://api.jquery.com/is/ and http://api.jquery.com/empty-selector/
EDIT:
As some have pointed, the browser interpretation of an empty element can vary. If you would like to ignore invisible elements such as spaces and line breaks and make the imple...
Why covariance and contravariance do not support value type
...or not.
You might want to read Eric Lippert's blog post on representation and identity for more on this topic in general.
EDIT: Having reread Eric's blog post myself, it's at least as much about identity as representation, although the two are linked. In particular:
This is why covariant and ...
How to scroll up or down the page to an anchor using jQuery?
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Description
You can do this using jQuery.offset() and jQuery.animate().
Check out the jsFiddle Demonstration.
Sample
function scrollToAnchor(aid){
var aTag = $("a[name='"+ aid +"']");
$('html,body').animate({scrollTop: aTag.offset().top},'slow');
}
scrollToAncho...