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Null check in an enhanced for loop
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You should better verify where you get that list from.
An empty list is all you need, because an empty list won't fail.
If you get this list from somewhere else and don't know if it is ok or not you could create a utility method and use it like this:
for( Object o : safe( list ) ) {
// do wh...
Definitive way to trigger keypress events with jQuery
I've read all the answers on to this questions and none of the solutions seem to work.
10 Answers
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Why doesn't height: 100% work to expand divs to the screen height?
...lement <html>, which can be a percentage height. .
So, you've given all of your elements height, except for the <html>, so what you should do is add this:
html {
height: 100%;
}
And your code should work fine.
* { padding: 0; margin: 0; }
html, body, #fullheight {
min-he...
What is a Java ClassLoader?
...om this nice tutorial from Sun:
Motivation
Applications written in statically compiled programming languages, such as C and C++, are compiled into native, machine-specific instructions and saved as an executable file. The process of combining the code into an executable native code is called linki...
How do you log server errors on django sites
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Well, when DEBUG = False, Django will automatically mail a full traceback of any error to each person listed in the ADMINS setting, which gets you notifications pretty much for free. If you'd like more fine-grained control, you can write and add to your settings a middlew...
What is reflection and why is it useful?
... say you have an object of an unknown type in Java, and you would like to call a 'doSomething' method on it if one exists. Java's static typing system isn't really designed to support this unless the object conforms to a known interface, but using reflection, your code can look at the object and fin...
How to check if a column exists in Pandas
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To check if one or more columns all exist, you can use set.issubset, as in:
if set(['A','C']).issubset(df.columns):
df['sum'] = df['A'] + df['C']
As @brianpck points out in a comment, set([]) can alternatively be constructed with curly...
“The page you are requesting cannot be served because of the extension configuration.” error message
...amework you are using.
This is a common issue and happens when IIS is installed after VS or .NET framework.
Note - for Windows 8/10 users, see the other answer by JohnOpincar below. And also the comment/tip from Kevin Brydon.
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What's the difference between commit() and apply() in SharedPreferences
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tl;dr:
commit() writes the data synchronously (blocking the thread its called from). It then informs you about the success of the operation.
apply() schedules the data to be written asynchronously. It does not inform you about the success of the operation.
If you save with apply() and immediately...
Understanding events and event handlers in C#
I understand the purpose of events, especially within the context of creating user interfaces. I think this is the prototype for creating an event:
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