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UITapGestureRecognizer - single tap and double tap
...am trying to add 2 UITapGestureRecognizers to a view, one for single tap and one for double tap events. The single tap recognizer is working as expected (on its own). But I don't seem to be able to get the double tap recognizer working.
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Stretch and scale CSS background
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That would work for Safari 3 (or later), Chrome, Opera 10+, Firefox 3.6+, and Internet Explorer 9 (or later).
For it to work with lower verions of Internet Explorer, try these CSS:
filter: progid:DXImageTransform.Microsoft.AlphaImageLoader(src='.myBackground.jpg', sizingMethod='scale');
-ms-fi...
What is the purpose of a self executing function in javascript?
... blocks of JavaScript code.
For example, as mentioned in a comment by Alexander:
(function() {
var foo = 3;
console.log(foo);
})();
console.log(foo);
This will first log 3 and then throw an error on the next console.log because foo is not defined.
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`staticmethod` and `abc.abstractmethod`: Will it blend?
In my Python app I want to make a method that is both a staticmethod and an abc.abstractmethod . How do I do this?
4 Ans...
Python group by
Assume that I have a set of data pair where index 0 is the value and index 1 is the type:
6 Answers
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Can't find the 'libpq-fe.h header when trying to install pg gem
...nx), 11.10 (Oneiric Ocelot), 12.04 (Precise Pangolin), 14.04 (Trusty Tahr) and 18.04 (Bionic Beaver)):
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/usr/include/postgresql/libpq-fe.h
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So try installing libpq-dev or its equivalent for your OS:
For Ubuntu/Debian systems: sudo apt-get install libpq-dev
On Red Hat Linux (RHEL) systems:...
How to check if running in Cygwin, Mac or Linux?
I have a shell script that is used both on Windows/Cygwin and Mac and Linux. It needs slightly different variables for each versions.
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Does the C++ standard mandate poor performance for iostreams, or am I just dealing with a poor imple
Every time I mention slow performance of C++ standard library iostreams, I get met with a wave of disbelief. Yet I have profiler results showing large amounts of time spent in iostream library code (full compiler optimizations), and switching from iostreams to OS-specific I/O APIs and custom buffer...
Understanding garbage collection in .NET
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You are being tripped up here and drawing very wrong conclusions because you are using a debugger. You'll need to run your code the way it runs on your user's machine. Switch to the Release build first with Build + Configuration manager, change the "Act...
How to detect if JavaScript is disabled?
...ection. As an alternative it is possible to set a cookie using JavaScript, and then test for that cookie using server-side scripting upon subsequent page views. However this would not be suitable for deciding what content to deliver as it would not be able to distinguish visitors without the cookie...