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Strange, unexpected behavior (disappearing/changing values) when using Hash default value, e.g. Hash
...lies 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 Hash.n...
Set padding for UITextField with UITextBorderStyleNone
I wanted to use a custom background for my UITextFields . This works fine except for the fact that I have to use UITextBorderStyleNone to make it look pretty. This forces the text to stick to the left without any padding.
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jQuery set checkbox checked
I already tried all the possible ways, but I still didn't get it working.
I have a modal window with a checkbox I want that when the modal opens, the checkbox check or uncheck should be based on a database value. (I have that already working with others form fields.) I started trying to get it c...
How can I set the default value for an HTML element?
I thought that adding a "value" attribute set on the <select> element below would cause the <option> containing my provided "value" to be selected by default:
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Why do we use Base64?
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Your first mistake is thinking that ASCII encoding and Base64 encoding are interchangeable. They are not. They are used for different purposes.
When you encode text in ASCII, you start with a text string and convert it to a sequence of bytes.
When...
Creating an Android trial application that expires after a fixed time period
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Currently most developers accomplish this using one of the following 3 techniques.
The first approach is easily circumvented, the first time you run the app save the date/time to a file, database, or shared preferences and every time you run the app after that check t...
How to import data from mongodb to pandas?
I have a large amount of data in a collection in mongodb which I need to analyze. How do i import that data to pandas?
12 A...
Aggregate / summarize multiple variables per group (e.g. sum, mean)
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The recast function (also from reshape2) integrates the melt and dcast function in one go for tasks like this: recast(df1, year + month ~ variable, sum, id.var = c("date", "year", "month"))
– Jaap
May 13 '16 at 6:17
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What does it mean to inflate a view from an xml file?
I am new to android development and keep coming across references to Inflating views from a layout xml file. I googled and searched the development guide but still wasn't able to pick up a sense for what it means. If someone could provide a very simple example, it'd be much appreciated.
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How to clear an ImageView in Android?
I am reusing ImageView s for my displays, but at some point I don't have values to put it.
17 Answers
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