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Rails: How can I set default values in ActiveRecord?
... of the available methods, but I believe that defining an after_initialize callback is the way to go for the following reasons:
default_scope will initialize values for new models, but then that will become the scope on which you find the model. If you just want to initialize some numbers to 0 the...
jQuery object equality
...-up". I use "$" just to make it clear what jQuery is doing.
Whenever you call $("#foo") you are actually doing a jQuery("#foo") which returns a new object. So comparing them and expecting same object is not correct.
However what you CAN do may be is something like:
<html>
<head>
<...
Convert JavaScript string in dot notation into an object reference
...
This is bad programming practice (unnecessary metaprogramming specifically, and kind of violates function side-effect-free coding style, and will have performance hits). Novices who find themselves in this case, should instead consider working with array representations, e.g. ['x','a','b','c']...
How do I pass multiple attributes into an Angular.js attribute directive?
...e:
<div example-directive example-number="99" example-function="exampleCallback()"></div>
Directive:
app.directive('exampleDirective ', function () {
return {
restrict: 'A', // 'A' is the default, so you could remove this line
scope: {
callback : '&a...
Setting focus on an HTML input box on page load
...focus attribute (works in all current browsers except IE9 and below). Only call your script if it's IE9 or earlier, or an older version of other browsers.
<input type="text" name="fname" autofocus>
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angular ng-repeat in reverse
...
You can just call a method on your scope to reverse it for you, like this:
<!doctype html>
<html ng-app="myApp">
<head>
<script src="http://code.jquery.com/jquery-1.9.1.min.js"></script>
<script s...
Android ImageView Zoom-in and Zoom-Out
...ort android.os.Bundle;
public class Zoomexample extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(new Zoom(this));
}
}
...
Hidden Features of SQL Server
...e allows to do this very easily - it allows access to the "virtual" tables called inserted and deleted (like in triggers):
DELETE FROM (table)
OUTPUT deleted.ID, deleted.Description
WHERE (condition)
If you're inserting values into a table which has an INT IDENTITY primary key field, with the OUT...
How to use the toString method in Java?
...e of the String.toString:
Whenever you require to explore the constructor called value in the String form, you can simply use String.toString...
for an example...
package pack1;
import java.util.*;
class Bank {
String n;
String add;
int an;
int bal;
int dep;
public Bank...
Adding a new array element to a JSON object
...ave a JSON format object I read from a JSON file that I have in a variable called teamJSON, that looks like this:
6 Answers...