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Check if a string is null or empty in XSLT
...] null or empty" as inferred from the question, including it's pseudo-code and my own early experience with XSLT. I.e., "What is the equivalent of the following Java?":
!(categoryName == null || categoryName.equals(""))
For more details e.g., distinctly identifying null vs. empty, see johnvey's a...
Android: Why does long click also trigger a normal click?
I have a ListView with listeners for a long click and a regular click.
4 Answers
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Get the current first responder without using a private API
I submitted my app a little over a week ago and got the dreaded rejection email today. It tells me that my app cannot be accepted because I'm using a non-public API; specifically, it says,
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List files with certain extensions with ls and grep
I just want to get the files from the current dir and only output .mp4 .mp3 .exe files nothing else.
So I thought I could just do this:
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What are the “standard unambiguous date” formats for string-to-date conversion in R?
... '"%Y-%m-%d"' then '"%Y/%m/%d"' on the first non-'NA' element,
and give an error if neither works.
as.Date("01 Jan 2000") yields an error because the format isn't one of the two listed above. as.Date("01/01/2000") yields an incorrect answer because the date isn't in one of the two fo...
How do you check in python whether a string contains only numbers?
...u'll want to use the isdigit method on your str object:
if len(isbn) == 10 and isbn.isdigit():
From the isdigit documentation:
str.isdigit()
Return True if all characters in the string are digits and there is at least one character, False otherwise. Digits include decimal characters and digits tha...
how to generate migration to make references polymorphic
I have a Products table and want to add a column:
4 Answers
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Change application's starting activity
I have created the meat and guts of my application but I want to add a different activity that will be the starting point (sort of a log-in screen).
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Git blame — prior commits?
... Can you get a complete history, without having to re-enter the command several times with different hashes?
– Anders Zommarin
Feb 23 '11 at 22:59
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How to pause for specific amount of time? (Excel/VBA)
...se the Wait method:
Application.Wait Now + #0:00:01#
or (for Excel 2010 and later):
Application.Wait Now + #12:00:01 AM#
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