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How to automatically convert strongly typed enum into int?
... like implicit conversion to indexes, seamless using of bitwise operations etc.. The new style enums added a really great scoping thing, but... You cannot use just that thing (even with explicit underlying type specification!). So now you're either forced to use old style enums with tricks like putt...
What is a NullPointerException, and how do I fix it?
...ou should know, Java types are divided into primitive types (boolean, int, etc.) and reference types. Reference types in Java allow you to use the special value null which is the Java way of saying "no object".
A NullPointerException is thrown at runtime whenever your program attempts to use a null...
How to save a Python interactive session?
...yself frequently using Python's interpreter to work with databases, files, etc -- basically a lot of manual formatting of semi-structured data. I don't properly save and clean up the useful bits as often as I would like. Is there a way to save my input into the shell (db connections, variable assi...
Right way to reverse pandas.DataFrame?
...a time series while remaining agnostic to the time step (day, month, year, etc.). So you may be working with a data frame, do a transformation on it, which messes up the indexing. It’s common to thus reindex the frame.
– Cybernetic
Jul 12 at 0:23
...
Why can't I define a static method in a Java interface?
...d. I believe static is a crummy term in languages anyway, and has been stretched too far as is. So having it by itself is already sketchy. See my example above stackoverflow.com/questions/512877/… {shrug}.
– user4229245
Sep 2 '16 at 18:14
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Preventing an image from being draggable or selectable without using JS
... 2012 */
-webkit-user-drag: none; /* Prevents dragging of images/divs etc */
user-drag: none;
}
JS:
var makeUnselectable = function( $target ) {
$target
.addClass( 'unselectable' ) // All these attributes are inheritable
.attr( 'unselectable', 'on' ) // For IE9 - This...
How to set OnClickListener on a RadioButton in Android?
...is to change and update the View accordingly (saves you having 2 or 3 or 4 etc listeners).
RadioGroup radioGroup = (RadioGroup) findViewById(R.id.yourRadioGroup);
radioGroup.setOnCheckedChangeListener(new OnCheckedChangeListener()
{
@Override
public void onCheck...
Git: How to remove file from historical commit?
...ociated with them. This means that stuff like signed commits, commit notes etc. are preserved
filter-branch keeps backups too, so the size of the repo won't decrease immediately unless you expire the reflogs and garbage collect:
rm -Rf .git/refs/original # careful
git gc --aggressive --prun...
matplotlib does not show my drawings although I call pyplot.show()
...ed all the different backends that people on the web suggest (Qt4Agg, GTK, etc.), and they all failed (i.e. when I tried to import matplotlib.pyplot, I get ImportError because it's trying to import some dependency that's missing). I then researched how to install those dependencies, but it just mad...
Why does pylint object to single character variable names?
...ic names I've used have been like ratio, denominator, obj_generator, path, etc. It may take an extra second or two to type them out, but the time you save trying to figure out what you wrote even half an hour from then is well worth it.
...