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What's wrong with overridable method calls in constructors?
...ohibit it:
There are a few more restrictions that a class must obey to allow inheritance. Constructors must not invoke overridable methods, directly or indirectly. If you violate this rule, program failure will result. The superclass constructor runs before the subclass constructor, so the overr...
What methods of ‘clearfix’ can I use?
...rt for oldIE, the solution can be simplified to one css statement. Additionally, using display: block (instead of display: table) allows margins to collapse properly when elements with clearfix are siblings.
.container::after {
content: "";
display: block;
clear: both;
}
This is the most mo...
How do I deserialize a JSON string into an NSDictionary? (For iOS 5+)
...zern answer
@implementation NSString (Extensions)
- (NSDictionary *) json_StringToDictionary {
NSError *error;
NSData *objectData = [self dataUsingEncoding:NSUTF8StringEncoding];
NSDictionary *json = [NSJSONSerialization JSONObjectWithData:objectData options:NSJSONReadingMutableContain...
Difference between addSubview and insertSubview in UIView class
...array then add in View'slayer
- (void)addSubview:(UIView *)subview
{
[_subviews addObject:subview];
[_layer addSublayer:subview.layer];
}
}
2.While insertSubview add your view as subview then call
[_layer insertSublayer:subview.layer atIndex:index];
- (void)insertSubview:(UIView *)subv...
What exactly does an #if 0 … #endif block do?
...entire thing. And the #if 0s will nest with each other, like so:
#if 0
pre_foo();
#if 0
foo();
bar(x, y); /* x must not be NULL */
baz();
#endif
quux();
#endif
Although of course this can get a bit confusing and become a maintenance headache if not commented properly.
...
How do you print in a Go test using the “testing” package?
...
Command go
Description of testing flags
-v
Verbose output: log all tests as they are run. Also print all
text from Log and Logf calls even if the test succeeds.
Package testing
func (*T) Log
func (c *T) Log(args ...interface{})
Log formats its arguments using default ...
Possible to perform cross-database queries with PostgreSQL?
...no longer supported, but if you need to do this in a pre-2013 Postgres installation, there is a function called dblink.
I've never used it, but it is maintained and distributed with the rest of PostgreSQL. If you're using the version of PostgreSQL that came with your Linux distro, you might need to...
Facebook share button and custom text [closed]
...cebook"
href="http://www.facebook.com/sharer.php?s=100&p[title]=YOUR_TITLE&p[summary]=YOUR_SUMMARY&p[url]=YOUR_URL&p[images][0]=YOUR_IMAGE_TO_SHARE_OBJECT"
target="_blank">
<span>
<img width="14" height="14" src="'icons/fb.gif" alt="Facebook" /> Facebook
...
Why does viewWillAppear not get called when an app comes back from the background?
...
In other words, if someone looks at another application or takes a phone call, then switches back to your app which was earlier on backgrounded, your UIViewController which was already visible when you left your app 'doesn't care' so to speak -- as far as it is concerned, it's never disappeared and...
Argparse optional positional arguments?
I have a script which is meant to be used like this:
usage: installer.py dir [-h] [-v]
3 Answers
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