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Strange, unexpected behavior (disappearing/changing values) when using Hash default value, e.g. Hash
...ior applies to any default value that is subsequently mutated (e.g. hashes and strings), not just arrays.
TL;DR: Use Hash.new { |h, k| h[k] = [] } if you want the most idiomatic solution and don’t care why.
What doesn’t work
Why Hash.new([]) doesn’t work
Let’s look more in-depth at why...
How to convert NSNumber to NSString
So I have an NSArray "myArray" with NSNumber s and NSString s. I need them in another UIView so i go like this:
7 Ans...
REST response code for invalid data
...tion failed is used for conditional requests when using last-modified date and ETags.
403 - Forbidden is used when the server wishes to prevent access to a resource.
The only other choice that is possible is 422 - Unprocessable entity.
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Get file name and extension in Ruby
...m working on a program to download a video from YouTube, convert it to MP3 and create a directory structure for the files.
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“Cannot evaluate expression because the code of the current method is optimized” in Visual Studio 20
I am using Visual Studio 2010 in debug mode and I have "optimize code" unchecked. I can't quick watch (or hover on) any variable in the debugger. I get this error "Cannot evaluate expression because the code of the current method is optimized".
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How to drop a list of rows from Pandas dataframe?
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Use DataFrame.drop and pass it a Series of index labels:
In [65]: df
Out[65]:
one two
one 1 4
two 2 3
three 3 2
four 4 1
In [66]: df.drop(df.index[[1,3]])
Out[66]:
one two
one 1 4
three ...
Android Endless List
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One solution is to implement an OnScrollListener and make changes (like adding items, etc.) to the ListAdapter at a convenient state in its onScroll method.
The following ListActivity shows a list of integers, starting with 40, adding items when the user scrolls to the end...
Download Github pull request as unified diff
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Great, thanks. And there is also .patch. Why is this not exposed in the GUI? How is one supposed to discover this?
– Thilo
May 31 '11 at 14:04
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How to provide animation when calling another activity in Android?
I have two Activities A and B. I want to have the shrink Animation when
Activity A calls B and maximize animation when Activity B calls A. I don't need the animation xml files for this.
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Why does the lock object have to be static?
... a private static readonly object for locking in multi threading.
I understand that private reduces the entry points to the locking object by tightening the encapsulation and therefore access to the most essential.
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