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Creating a blurring overlay view
...this effect. This is a native API that has been fine-tuned for performance and great battery life, plus it's easy to implement.
Swift:
//only apply the blur if the user hasn't disabled transparency effects
if !UIAccessibility.isReduceTransparencyEnabled {
view.backgroundColor = .clear
let...
What is mutex and semaphore in Java ? What is the main difference?
What is mutex and semaphore in Java ? What is the main difference ?
11 Answers
11
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How do I calculate the date in JavaScript three months prior to today?
...tation needed. But more than half the time, that is 31 days ago, not 30. And if today is the 31st of the month (and it isn't August or Decemeber), that day of the month doesn't exist in the previous month.
Interestingly, Google agrees with JavaScript if you ask it what day is one month before ano...
Should I instantiate instance variables on declaration or in the constructor?
...he compiler.
The first variant is more readable.
You can't have exception handling with the first variant.
There is additionally the initialization block, which is as well put in the constructor(s) by the compiler:
{
a = new A();
}
Check Sun's explanation and advice
From this tutorial:
...
Once upon a time, when > was faster than < … Wait, what?
...tc. He also explains that the actual meaning of depth values (which is top and which isn't) can also be customized. I understand so far. And then the author says something unbelievable:
...
Is there a way to check if int is legal enum in C#?
I've read a few SO posts and it seems most basic operation is missing.
8 Answers
8
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Rotating videos with FFmpeg
...ut.mov
For the transpose parameter you can pass:
0 = 90CounterCLockwise and Vertical Flip (default)
1 = 90Clockwise
2 = 90CounterClockwise
3 = 90Clockwise and Vertical Flip
Use -vf "transpose=2,transpose=2" for 180 degrees.
Make sure you use a recent ffmpeg version from here (a static build wi...
How to replace spaces in file names using a bash script
...end a safe solution to recursively replace spaces with underscores in file and directory names starting from a given root directory? For example:
...
How to maintain a Unique List in Java?
... no duplicate elements. More formally, sets contain no pair of elements e1 and e2 such that e1.equals(e2), and at most one null element. As implied by its name, this interface models the mathematical set abstraction.
Note: Great care must be exercised if mutable objects are used as set elements...
Best way to parseDouble with comma as decimal separator?
... To further mess things up, some locales use comma as a thousands separator, in which case "1,234" would parse to 1234.0 instead of throwing an error.
– Joonas Pulakka
Dec 1 '10 at 11:11
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