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What is the easiest way to duplicate an activerecord record?
...y of an activerecord record, changing a single field in the process (in addition to the id ). What is the simplest way to accomplish this?
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You need to use a Theme.AppCompat theme (or descendant) with this activity
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The reason you are having this problem is because the activity you are trying to apply the dialog theme to is extending ActionBarActivity which requires the AppCompat theme to be applied.
Update: Extending AppCompatActivity would also have this problem
In this case, change the ...
How do I directly modify a Google Chrome Extension File? (.CRX)
I'm not sure in which languages those extensions are, I think the are written in Html, Javascript or JSON. As far as I know they are "compressed" in a .CRX file.
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Regular vs Context Free Grammars
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Regular grammar is either right or left linear, whereas context free grammar is basically any combination of terminals and non-terminals. Hence you can see that regular grammar is a subset of context-free grammar.
So for a palindrome for instan...
Set default CRAN mirror permanent in R
...t repos in your .Rprofile to restore your choice every time you start R
Edit: to be more precise:
Add
options(repos=structure(c(CRAN="YOUR FAVORITE MIRROR")))
to your .Rprofile
Alternatively, you can set the mirror site-wide in your Rprofile.site. The location of the file is given by ?Start...
How to make an HTTP request + basic auth in Swift
I have a RESTFull service with basic authentication and I want to invoke it from iOS+swift. How and where I must provide Credential for this request?
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Most efficient way to concatenate strings?
...ilder sb = new StringBuilder();
sb.Append(someString);
The only problem with String.Join is that you have to concatenate the strings with a common delimiter.
Edit: as @ryanversaw pointed out, you can make the delimiter string.Empty.
string key = String.Join("_", new String[]
{ "Customers_Contac...
What is the difference between SIGSTOP and SIGTSTP?
...ignals are designed to suspend a process which will be eventually resumed with SIGCONT. The main differences between them are:
SIGSTOP is a signal sent programmatically (eg: kill -STOP pid ) while SIGTSTP (for signal - terminal stop) may also be sent through the tty driver by a user typing on a ke...
CSS selector with period in ID
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Classic. Just after digging through all the specs writing the question, I read through it some more and found there is an escape character. I've never needed it before, but the CSS spec does allow for backslash (\) escaping like most languages. What do you know?
So in my exam...
Resize HTML5 canvas to fit window
How can I automatically scale the HTML5 <canvas> element to fit the page?
15 Answers
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