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Why is the default value of the string type null instead of an empty string?
It's quite annoying to test all my strings for null before I can safely apply methods like ToUpper() , StartWith() etc...
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Container-fluid vs .container
...he viewport that the webpage is being viewed on, the container class gives its div a specific fixed width. These lines don't exist in any form for container-fluid, so its width changes every time the viewport width changes.
So for example, say your browser window is 1000px wide. As it's greater tha...
Using ZXing to create an Android barcode scanning app [duplicate]
...);
intent.putExtra("SCAN_MODE", "QR_CODE_MODE");
startActivityForResult(intent, 0);
}
};
public void onActivityResult(int requestCode, int resultCode, Intent intent) {
if (requestCode == 0) {
if (resultCode == RESULT_OK) {
String contents = intent.getStri...
How to prevent Node.js from exiting while waiting for a callback?
...re empty. A callback is added to an event queue when a call such as
emmiter1.on('this_event',callback).
has executed. This call is part of the code written by the module developer .
If a module is a quick port from a synchronous/blocking version, this may not happen til some part of the oper...
How to install MySQLdb (Python data access library to MySQL) on Mac OS X?
...d the universe according to google includes numerous references to what a PITA it is, and an inordinate number of guides that seem to be outdated. Given that this site is intended to address these sorts of problems, and I know that I'm going to need a reference to the solution in future, I'm going ...
Can I call a base class's virtual function if I'm overriding it?
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Is there any possible issues with doing this? Is it bad practice?
– Robben_Ford_Fan_boy
Feb 2 '11 at 15:01
37
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Show which git tag you are on?
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Edit: Jakub Narębski has more git-fu. The following much simpler command works perfectly:
git describe --tags
(Or without the --tags if you have checked out an annotated tag. My tag is lightweight, so I need the --tags.)
o...
How can you find the height of text on an HTML canvas?
...has a context.measureText(text) function that will tell you how much width it would require to print that text, but I can't find a way to find out how tall it is. I know it's based on the font, but I don't know to convert a font string to a text height.
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Why is Multiple Inheritance not allowed in Java or C#?
I know that multiple inheritance is not allowed in Java and C#. Many books just say, multiple inheritance is not allowed. But it can be implemented by using interfaces. Nothing is discussed about why it is not allowed. Can anybody tell me precisely why it is not allowed?
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Difference between HashMap, LinkedHashMap and TreeMap
...ee classes implement the Map interface and offer mostly the same functionality. The most important difference is the order in which iteration through the entries will happen:
HashMap makes absolutely no guarantees about the iteration order. It can (and will) even change completely when new element...