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HTML anchor link - href and onclick both?
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130
Just return true instead?
The return value from the onClick code is what determines whether the...
ActiveRecord, has_many :through, and Polymorphic Associations
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edited Dec 5 '11 at 9:09
answered Nov 5 '09 at 23:53
Em...
Python Dictionary Comprehension
... like.
>>> d = {n: n**2 for n in range(5)}
>>> print d
{0: 0, 1: 1, 2: 4, 3: 9, 4: 16}
If you want to set them all to True:
>>> d = {n: True for n in range(5)}
>>> print d
{0: True, 1: True, 2: True, 3: True, 4: True}
What you seem to be asking for is a way ...
How ListView's recycling mechanism works
...rve that in my code. If you had a checkbox and if you check it at position 0(let's say item1 had a checkbox and you checked it) so when you scroll down you will see item 8 checkbox already checked, this is why listview is re using the same view, not creating a new for you due to performance optimiza...
Select rows which are not present in other table
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+500
There are basically 4 techniques for this task, all of them standard SQL.
NOT EXISTS
Often fastest in Postgres.
SELECT ip
FROM ...
Test if a command outputs an empty string
...r success, non-zero for failure). For example:
files=$(ls -A)
if [[ $? != 0 ]]; then
echo "Command failed."
elif [[ $files ]]; then
echo "Files found."
else
echo "No files found."
fi
More info here.
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targetContentOffsetForProposedContentOffset:withScrollingVelocity without subclassing UICollectionVi
...m I have this...
- (void)awakeFromNib
{
self.itemSize = CGSizeMake(75.0, 75.0);
self.minimumInteritemSpacing = 10.0;
self.minimumLineSpacing = 10.0;
self.scrollDirection = UICollectionViewScrollDirectionHorizontal;
self.sectionInset = UIEdgeInsetsMake(10.0, 10.0, 10.0, 10.0);
}
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Rails find record with zero has_many records associated [duplicate]
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Bah, found it here: https://stackoverflow.com/a/5570221/417872
City.includes(:photos).where(photos: { city_id: nil })
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Does .NET have a way to check if List a contains all items in List b?
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answered Oct 5 '09 at 15:06
Jon SkeetJon Skeet
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How do I convert an interval into a number of hours with postgres?
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Probably the easiest way is:
SELECT EXTRACT(epoch FROM my_interval)/3600
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