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Detect if Android device has Internet connection
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You are right. The code you've provided only checks if there is a network connection.
The best way to check if there is an active Internet connection is to try and connect
to a known server via http.
public static boolean hasActiveIn...
How do JavaScript closures work?
...h a knowledge of the concepts they consist of (for example functions, variables and the like), but does not understand closures themselves?
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How to change the font on the TextView?
How to change the font in a TextView , as default it's shown up as Arial? How to change it to Helvetica ?
16 Answers
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How to get instance variables in Python?
Is there a built-in method in Python to get an array of all a class' instance variables? For example, if I have this code:
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CSS background image to fit width, height should auto-scale in proportion
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There is a CSS3 property for this, namely background-size (compatibility check). While one can set length values, it's usually used with the special values contain and cover. In your specific case, you should use cover:
body {
background-image: url(images/backgro...
Java 8 Stream and operation on arrays
I have just discovered the new Java 8 stream capabilities. Coming from Python, I was wondering if there was now a neat way to do operations on arrays like summing, multiplying two arrays in a "one line pythonic" way ?
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Get file name from URI string in C#
I have this method for grabbing the file name from a string URI. What can I do to make it more robust?
8 Answers
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How can I map True/False to 1/0 in a Pandas DataFrame?
I have a column in python pandas DataFrame that has boolean True/False values, but for further calculations I need 1/0 representation. Is there a quick pandas/numpy way to do that?
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WebRTC vs Websockets: If WebRTC can do Video, Audio, and Data, why do I need Websockets? [closed]
So I'm looking to build a chat app that will allow video, audio, and text. I spent some time researching into Websockets and WebRTC to decide which to use. Since there are plenty of video and audio apps with WebRTC, this sounds like a reasonable choice, but are there other things I should consider? ...
Drop rows with all zeros in pandas data frame
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It turns out this can be nicely expressed in a vectorized fashion:
> df = pd.DataFrame({'a':[0,0,1,1], 'b':[0,1,0,1]})
> df = df[(df.T != 0).any()]
> df
a b
1 0 1
2 1 0
3 1 1
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