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How to check null objects in jQuery
... FAQ...
You can use the length property of the jQuery collection returned by your selector:
if ( $('#myDiv').length ){}
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Eclipse / Android : “Errors running builder 'Android Pre Compiler' on project…”
...swered Jan 22 '13 at 11:23
Mick ByrneMick Byrne
13.3k1313 gold badges6767 silver badges8383 bronze badges
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How to calculate time elapsed in bash script?
...ate +%s (which is a GNU extension), it's portable to all systems supported by Bash.
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Rebuild or regenerate 'ic_launcher.png' from images in Android Studio
... click on res folder > New image asset
browser to the icon. Click next
By default the icon goes to src/debug/res- keep this
In the project hierarchy, browse to src/debug/res and copy the files from the drawable*
directories to the same directories in src/main and src/main
copy the src/debug/res...
Is it possible to set a number to NaN or infinity?
... imageUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454...
Rake just one migration
...heck the timestamps (Migration ID) for the previous migrations you've done by using
rake db:migrate:status
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'Must Override a Superclass Method' Errors after importing a project into Eclipse
...ntioned (like in the comments to the other answers) a clean build followed by a restart is often required.
– gsingh2011
May 23 '13 at 3:45
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Extract date (yyyy/mm/dd) from a timestamp in PostgreSQL
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You can cast your timestamp to a date by suffixing it with ::date. Here, in psql, is a timestamp:
# select '2010-01-01 12:00:00'::timestamp;
timestamp
---------------------
2010-01-01 12:00:00
Now we'll cast it to a date:
wconrad=# select '2010-...
How to delete last item in list?
...anged, with del record[-1] or record.pop() the list is changed. (as stated by @pltrdy in the comments)
Note 2: The code could use some Python idioms. I highly recommend reading this:
Code Like a Pythonista: Idiomatic Python (via wayback machine archive).
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How can i use iptables on centos 7? [closed]
...ave you made sure the iptables service is started at boot? You can do this by running 'systemctl enable iptables'
– Sgaduuw
Jul 21 '14 at 10:01
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