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UICollectionView's cellForItemAtIndexPath is not being called
...ctionView cellForItemAtIndexPath:(NSIndexPath *)indexPath
was not being called was because of the itemSize for the collectionViewFlowLayout's height was too big.
[self.myCollectionViewFlowLayout setItemSize:CGSizeMake(320, 548)];
If I change the height to 410, it will execute cellForItemAtIndex...
Find document with array that contains a specific value
...
@AeroWang use this db.person.find( { favouriteFoods: { $all: ["sushi", "sashimi"] } } ) will return all person loving both "sushi" and "sashimi" someone pointed it a few answers below
– benraay
Jul 1 at 14:20
...
Swift make method parameter mutable?
...eclare an inout parameter. Think: passing in a pointer.
func reduceToZero(_ x: inout Int) {
while (x != 0) {
x = x-1
}
}
var a = 3
reduceToZero(&a)
print(a) // will print '0'
This can be particularly useful in recursion.
Apple's inout declaration guidelines can be found...
Adding gif image in an ImageView in android
...imationActivity: -
public class AnimationActivity extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
InputStream stream = null;
try {
stream = getAssets().open("pig...
Create a string of variable length, filled with a repeated character
...slower than a string-concatenation-based implementation. It performs especially badly on large strings. See below for full performance details.
On Firefox, Chrome, Node.js MacOS, Node.js Ubuntu, and Safari, the fastest implementation I tested was:
function repeatChar(count, ch) {
if (count == ...
Unable to open project… cannot be opened because the project file cannot be parsed
...
this should be marked as the answer. Really good stuff, thanks
– owen gerig
May 10 '13 at 15:10
12
...
What does “export” do in shell programming? [duplicate]
... '^variable='
$ # No environment variable called variable
$ variable=Hello # Create local (non-exported) variable with value
$ env | grep '^variable='
$ # Still no environment variable called variable
$ export variable ...
Named colors in matplotlib
... have been moved under the 'xkcd:' prefix since I posted this answer originally.
I really didn't change much from the matplotlib example, but here is the code for completeness.
import matplotlib.pyplot as plt
from matplotlib import colors as mcolors
colors = dict(mcolors.BASE_COLORS, **mcolors...
If my interface must return Task what is the best way to have a no-operation implementation?
...mprove performance even more if you cache the already completed task since all instances of completed tasks are the same:
public static class TaskExtensions
{
public static readonly Task CompletedTask = Task.FromResult(false);
}
With TaskExtensions.CompletedTask you can use the same instance ...
CGridCellNumeric - A numeric cell class for the MFC Grid - C/C++ - 清...
...t of the cell.
Input validation is done on the fly as the user is typing. All validation is done in the EN_UPDATE message handler, so any cut/copy and paste operations are immediately validated. If the user deletes the text in the cell, the value is set to zero.
Using the CGridCellNumeri...