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Fastest way to get the first object from a queryset in django?
... @Ben: QuerySet.__nonzero__() is never called since the QuerySet is converted to a list before checking for trueness. Other exceptions may still occur however.
– Ignacio Vazquez-Abrams
Feb 26 '11 at 0:07
...
How to “properly” print a list?
...f the steps in @TokenMacGuy's one-liner. First he uses the map function to convert each item in the list to a string (actually, he's making a new list, not converting the items in the old list). Then he's using the string method join to combine those strings with ', ' between them. The rest is just ...
snprintf and Visual Studio 2010
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Short story: Microsoft has finally implemented snprintf in Visual Studio 2015. On earlier versions you can simulate it as below.
Long version:
Here is the expected behavior for snprintf:
int snprintf( char* buffer, std::size_t buf_size, const char* format, ... );
Wr...
Simultaneously merge multiple data.frames in a list
..., by = "i")
# A tibble: 3 x 4
# i j k l
# <chr> <int> <int> <int>
# 1 a 1 NA 9
# 2 b 2 4 NA
# 3 c 3 5 7
You can also perform other joins, such as a full_join or inner_join:
list(x, y, z) %>% reduce(full_join, by = "i...
Retrieve a Fragment from a ViewPager
...r(FragmentManager fm) {
super(fm);
}
@Override
public int getCount() {
return ...;
}
@Override
public Fragment getItem(int position) {
return MyFragment.newInstance(...);
}
@Override
public Object instantiateItem(ViewGroup container, in...
How to programmatically round corners and set random background colors
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Consider using PaintDrawable instead of GradientDrawable. It supports rounded corners and just a single color which seems to be more appropriate than a gradient.
– Cimlman
Mar 16 '16 at 15:45
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android EditText - finished typing event
...er() {
@Override
public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
if (actionId == EditorInfo.IME_ACTION_SEARCH ||
actionId == EditorInfo.IME_ACTION_DONE ||
event != null &&
event....
Is it possible to get all arguments of a function as single object inside that function?
... end])
Array.indexOf(searchElement[, fromIndex])
I think the best way to convert a arguments object to a real Array is like so:
argumentsArray = [].slice.apply(arguments);
That will make it an array;
reusable:
function ArgumentsToArray(args) {
return [].slice.apply(args);
}
(function() {...
How to insert a SQLite record with a datetime set to 'now' in Android application?
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so above you are taking a Date object and converting it to a string to be placed in a sqlite column.. but when you pull that string from the database, how do you convert it back to a Date object?
– erik
Apr 30 '15 at 3:34
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Change from SQLite to PostgreSQL in a fresh Rails project
...in SQLite (The dev and production). Since I am moving to heroku, I want to convert my database to PostgreSQL.
13 Answers
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