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iPhone - Grand Central Dispatch main thread
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Dispatching a block to the main queue is usually done from a background queue to signal that some background processing has finished e.g.
- (void)doCalculation
{
//you can use any string instead "com.mycompany.myqueue"
dispatch_qu...
What is the python keyword “with” used for? [duplicate]
...en if exceptions are thrown. It provides 'syntactic sugar' for try/finally blocks.
From Python Docs:
The with statement clarifies code that previously would use try...finally blocks to ensure that clean-up code is executed. In this section, I’ll discuss the statement as it will commonly be used. ...
Vertically align an image inside a div with responsive height
...e same time:
Vertical Alignment
1) In this approach, we create an inline-block (pseudo-)element as the first (or last) child of the parent, and set its height property to 100% to take all the height of its parent.
2) Also, adding vertical-align: middle keeps the inline(-block) elements at the mid...
Is there a way to collapse all code blocks in Eclipse?
Eclipse has that "+/-" on the left to expand and collapse blocks of code.
15 Answers
1...
Does Firefox support position: relative on table elements?
... +1 This is the only solution that worked for me. Using tr {display:block} completely ruins the layout.
– Wesley Murch
Dec 14 '11 at 21:30
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vertical-align with Bootstrap 3
... use a custom class when you need it:
.vcenter {
display: inline-block;
vertical-align: middle;
float: none;
}
<div class="row">
<div class="col-xs-5 col-md-3 col-lg-1 vcenter">
<div style="height:10em;border:1px solid #000">Big</div>
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What is the ideal data type to use when storing latitude / longitude in a MySQL database?
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Google provides a start to finish PHP/MySQL solution for an example "Store Locator" application with Google Maps. In this example, they store the lat/lng values as "Float" with a length of "10,6"
http://code.google.com/apis/maps/articles/phpsqlsearch.html
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How to make MySQL handle UTF-8 properly
...r should be in UTF-8 (see my.cnf). remember any languages you use (such as PHP) must be UTF-8 as well. Some versions of PHP will use their own MySQL client library, which may not be UTF-8 aware.
If you do want to migrate existing data remember to backup first! Lots of weird choping of data can hap...
In Python, if I return inside a “with” block, will the file still close?
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Yes, it acts like the finally block after a try block, i.e. it always executes (unless the python process terminates in an unusual way of course).
It is also mentioned in one of the examples of PEP-343 which is the specification for the with statement:
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Blocks on Swift (animateWithDuration:animations:completion:)
I'm having trouble making the blocks work on Swift. Here's an example that worked (without completion block):
7 Answers
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