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How to play a local video with Swift?
... should add it using the plus button
3. Code
Open your View Controller and write this code.
import UIKit
import AVKit
import AVFoundation
class ViewController: UIViewController {
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
playVideo()
...
What's the $unwind operator in MongoDB?
...om your mind. The way that it stores your data is in the form of documents and collections, which allows for a dynamic means of adding and obtaining the data from your storage locations.
That being said, in order to understand the concept behind the $unwind parameter, you first must understand what...
What does Docker add to lxc-tools (the userspace LXC tools)?
... "lxc" refers to capabilities of the linux kernel (specifically namespaces and control groups) which allow sandboxing processes from one another, and controlling their resource allocations.
On top of this low-level foundation of kernel features, Docker offers a high-level tool with several powerful...
How do I split a string on a delimiter in Bash?
...
You can set the internal field separator (IFS) variable, and then let it parse into an array. When this happens in a command, then the assignment to IFS only takes place to that single command's environment (to read ). It then parses the input according to the IFS variable value in...
Cocoa: What's the difference between the frame and the bounds?
UIView and its subclasses all have the properties frame and bounds . What's the difference?
12 Answers
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Sending files using POST with HttpURLConnection
Since the Android developers recommend to use the HttpURLConnection class, I was wondering if anyone can provide me with a good example on how to send a bitmap "file" (actually an in-memory stream) via POST to an Apache HTTP server. I'm not interested in cookies or authentication or anything com...
How does a public key verify a signature?
...m trying to get a better grapple on how public/private keys work. I understand that a sender may add a digital signature to a document using his/her private key to essentially obtain a hash of the document, but what I do not understand is how the public key can be used to verify that signature.
...
Evaluating a mathematical expression in a string
...ppend(toks[0])
def pushUMinus(self, strg, loc, toks):
if toks and toks[0] == '-':
self.exprStack.append('unary -')
def __init__(self):
"""
expop :: '^'
multop :: '*' | '/'
addop :: '+' | '-'
integer :: ['+' | '-'] '0'..'9'+
...
Select first row in each GROUP BY group?
... BY p.customer) y ON y.customer = x.customer
AND y.max_total = x.total
GROUP BY x.customer, x.total
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Why is require_once so bad to use?
...
require_once and include_once both require that the system keeps a log of what's already been included/required. Every *_once call means checking that log. So there's definitely some extra work being done there but enough to detriment th...