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Does Android support near real time push notification?
...M. It inherits GCM’s core infrastructure to deliver messages reliably on Android, iOS and Chrome. However they'll continue to support GCM because lot of developers are using GCM SDKs today to handle notifications, and client app upgrade takes time.
As of June 26, 2012, Google Cloud Messaging is t...
error: ‘NULL’ was not declared in this scope
...
NULL is not a keyword. It's an identifier defined in some standard headers. You can include
#include <cstddef>
To have it in scope, including some other basics, like std::size_t.
share
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Flask-SQLAlchemy import/context issue
...y
db = SQLAlchemy()
class Member(db.Model):
# fields here
pass
And then in your application setup you can call init_app:
# apps.application.py
from flask import Flask
from apps.members.models import db
app = Flask(__name__)
# later on
db.init_app(app)
This way you can avoid cyclical ...
CSS to line break before/after a particular `inline-block` item
... is a good way to do what you want to do. Anything you insert using :after and content has exactly the same syntactic and semantic validity it would have done if you had just written it in there yourself.
The tools CSS provide work. You should just float the lis and then clear: left when you want t...
In Python, how do you convert seconds since epoch to a `datetime` object?
...datetime.utcfromtimestamp creates a naive timestamp. I had to import pytz and use datetime.fromtimestamp(1423524051, pytz.utc) to create an aware datetime.
– Matt
Feb 9 '15 at 23:21
...
Stretch and scale a CSS image in the background - with CSS only
I want that my background image stretch and scale depending on the browser viewport size.
22 Answers
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Strings as Primary Keys in SQL Database [closed]
I am not very familiar with databases and the theories behind how they work. Is it any slower from a performance standpoint (inserting/updating/querying) to use Strings for Primary Keys than integers?
...
Plain Old CLR Object vs Data Transfer Object
...POCO follows the rules of OOP. It should (but doesn't have to) have state and behavior. POCO comes from POJO, coined by Martin Fowler [anecdote here]. He used the term POJO as a way to make it more sexy to reject the framework heavy EJB implementations. POCO should be used in the same context in...
How to export JavaScript array info to csv (on client side)?
... this nature but I need to do this using JavaScript. I am using Dojo 1.8 and have all the attribute info in array, which looks like this:
...
Why does my JavaScript code receive a “No 'Access-Control-Allow-Origin' header is present on the req
...tpRequest:
Regular web pages can use the XMLHttpRequest object to send and receive data from remote servers, but they're limited by the same origin policy. Extensions aren't so limited. An extension can talk to remote servers outside of its origin, as long as it first requests cross-origin permi...