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Why historically do people use 255 not 256 for database field magnitudes?
...nagement likes powers of 2. see: stackoverflow.com/questions/3190146/… Allocating char foo[257] will either fragment memory or take up 512 bytes.
– ebyrob
Jan 26 '17 at 17:11
4...
How can I create a UILabel with strikethrough text?
...
NSMutableAttributedString *attributeString = [[NSMutableAttributedString alloc] initWithString:@"Your String here"];
[attributeString addAttribute:NSStrikethroughStyleAttributeName
value:@2
range:NSMakeRange(0, [attributeString length])];
Swift
le...
How do I make a UITableViewCell appear disabled?
...:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
}
// Configure the cell...
if(indexPath.row==0)
{
cell.userInteractionEnabled=FALSE;
UIImageVi...
Java dynamic array sizes?
...
No you can't change the size of an array once created. You either have to allocate it bigger than you think you'll need or accept the overhead of having to reallocate it needs to grow in size. When it does you'll have to allocate a new one and copy the data from the old to the new:
int[] oldItems ...
Why would I ever use push_back instead of emplace_back?
... the destructor will attempt to call delete on that pointer, which was not allocated by new because it is just a stack object. This leads to undefined behavior.
This is not just invented code. This was a real production bug I encountered. The code was std::vector<T *>, but it owned the conten...
Label Alignment in iOS 6 - UITextAlignment deprecated
...fine ALIGN_CENTER UITextAlignmentCenter
#endif
UILabel* label = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 50, 30)];
label.text = @"There is no spoon";
label.textAlignment = ALIGN_CENTER;
[self addSubview:label];
shar...
What are the mechanics of short string optimization in libc++?
... minus 2 bytes to store a short string (i.e. largest capacity() without an allocation).
On a 32 bit machine, 10 chars will fit in the short string. sizeof(string) is 12.
On a 64 bit machine, 22 chars will fit in the short string. sizeof(string) is 24.
A major design goal was to minimize sizeof(...
Adding Core Data to existing iPhone project
...dinator != nil) {
_managedObjectContext = [[NSManagedObjectContext alloc] init];
[_managedObjectContext setPersistentStoreCoordinator:coordinator];
}
return _managedObjectContext;
}
- (NSManagedObjectModel *)managedObjectModel{
if (_managedObjectModel != nil) {
r...
How to convert NSDate into unix timestamp iphone sdk?
...TimeStamp
{
NSDateFormatter *objDateformat = [[NSDateFormatter alloc] init];
[objDateformat setDateFormat:@"yyyy-MM-dd"];
NSString *strTime = [objDateformat stringFromDate:[NSDate date]];
NSString *strUTCTime = [self GetUTCDateTimeFromLocalTime:strTime];//Yo...
How can I concatenate NSAttributedStrings?
...
NSMutableAttributedString *mutableAttString = [[NSMutableAttributedString alloc] init];
NSString *plainString = // ...
NSDictionary *attributes = // ... a dictionary with your attributes.
NSAttributedString *newAttString = [[NSAttributedString alloc] initWithString:plainString attributes:attribute...