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differentiate null=True, blank=True in django
When we add a database field in django we generally write:
18 Answers
18
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How can I access getSupportFragmentManager() in a fragment?
...
You can directly call
getFragmentManager()
to get the fragment manager.
or
In your fragment,
Create field :
private FragmentActivity myContext;
override onAttach method of your fragment :
@Override
public void onAttach(Activity ...
Remove or uninstall library previously added : cocoapods
...en by Kyle Fuller - deintegrate, I'll post the proper workflow here:
Install clean:
$ sudo gem install cocoapods-clean
Run deintegrate in the folder of the project:
$ pod deintegrate
Clean:
$ pod clean
Modify your podfile (delete the lines with the pods you don't want to use anymore) and run...
How can I get pg_dump to authenticate properly
...ing host variable PGPASSWORD and .pgpass and neither of these two will allow me to authenticate to the database. I have chmod 'd .pgpass to appropriate permissions and also tried:
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advantage of tap method in ruby
...= User.new
user.username = "foobar"
user.save!
they would have to follow all the three lines and then recognize that it is just creating an instance named user.
If it were:
user = User.new.tap do |u|
u.username = "foobar"
u.save!
end
then that would be immediately clear. A reader would not...
Removing empty lines in Notepad++
...g like a regular expression.
You have to be in Extended mode
If you want all the lines to end up on a single line use \r\n. If you want to simply remove empty lines, use \n\r as @Link originally suggested.
Replace either expression with nothing.
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Creation timestamp and last update timestamp with Hibernate and MySQL
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thanks bro such a small thing need to update timestamp. I didnt know. you saved my day.
– Virendra Sagar
Jan 27 '17 at 14:28
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Custom CSS Scrollbar for Firefox
...ording to the spec. Both thin and a specific length may not do anything on all platforms, and what exactly it does is platform-specific. In particular, Firefox doesn't appear to be currently support a specific length value (this comment on their bug tracker seems to confirm this). The thin keywork d...
How to set standard encoding in Visual Studio
...erwise-default codepage.
Also, which files are not being saved as UTF-8? All of my .cs, .csproj, .sln, .config, .as*x, etc, all save as UTF-8 (with signature, the byte order marks), by default.
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Creating range in JavaScript - strange syntax
...guments
How the Number function handles arguments
What Function.prototype.call does
They're rather advanced topics in javascript, so this will be more-than-rather long. We'll start from the top. Buckle up!
1. Why not just Array(5).map?
What's an array, really? A regular object, containing intege...