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Chrome desktop notification example [closed]
...sktop notifications - simple to trigger, work as long as the page is open, and may disappear automatically after a few seconds
Service Worker notifications - a bit more complicated, but they can work in the background (even after the page is closed), are persistent, and support action buttons
The ...
What's the difference between SoftReference and WeakReference in Java?
What's the difference between java.lang.ref.WeakReference and java.lang.ref.SoftReference ?
12 Answers
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What is the most efficient/elegant way to parse a flat table into a tree?
..., we can say that all popular SQL databases support recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* FROM MyTABLE AS m JOIN MyTree AS t ON m.ParentId = t.Id
)
SELECT * FROM MyTree;
I tested recursive que...
What is the difference between NaN and None?
I am reading two columns of a csv file using pandas readcsv() and then assigning the values to a dictionary. The columns contain strings of numbers and letters. Occasionally there are cases where a cell is empty. In my opinion, the value read to that dictionary entry should be None but instead ...
Difference between git checkout --track origin/branch and git checkout -b branch origin/branch
Does anybody know the difference between these two commands to switch and track a remote branch?
4 Answers
...
UIView frame, bounds and center
...to add more correct content.
First a recap on the question: frame, bounds and center and theirs relationships.
Frame A view's frame (CGRect) is the position of its rectangle in the superview's coordinate system. By default it starts at the top left.
Bounds A view's bounds (CGRect) expresses a vie...
Where can I find my Azure account name and account key?
I am starting with Windows Azure. I have an Azure account with Microsoft and would like to use it from my Visual Studio project
...
How to decide font color in white or black depending on background color?
...need to break the hex code into 3 pieces to get the individual red, green, and blue intensities. Each 2 digits of the code represent a value in hexadecimal (base-16) notation. I won't get into the details of the conversion here, they're easy to look up.
Once you have the intensities for the individ...
Advantages of using display:inline-block vs float:left in CSS
...ck
The only drawback to the display: inline-block approach is that in IE7 and below an element can only be displayed inline-block if it was already inline by default. What this means is that instead of using a <div> element you have to use a <span> element. It's not really a huge drawb...
“R cannot be resolved to a variable”? [duplicate]
In Eclipse, I've created a project from a source and now it shows errors - "R cannot be resolved to a variable". From what I found here, I had cleared and rebuilt the project, but still the R file doesn't appear in the /gen folder.
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