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iPhone: Detecting user inactivity/idle time since last screen touch
... touch or an Ended touch, to reduce the number of timer resets.
NSSet *allTouches = [event allTouches];
if ([allTouches count] > 0) {
// allTouches count only ever seems to be 1, so anyObject works here.
UITouchPhase phase = ((UITouch *)[allTouches anyObject]).phase;
...
Run a callback only if an attribute has changed in Rails
...
Rails 5.1+
class Page < ActiveRecord::Base
before_save :do_something, if: :will_save_change_to_status_id?
private
def do_something
# ...
end
end
The commit that changed ActiveRecord::Dirty is here: https://github.com/rails/rails/commit/16ae3db5a5c6a08383b974ae...
Django admin: How to display a field that is marked as editable=False' in the model?
...
+1. Especially if you don't plan to edit the field at all in Admin.
– Manoj Govindan
Oct 19 '10 at 16:05
...
Can Objective-C switch on NSString?
... @abbood For more information about enum, see the posting NS_ENUM & NS_OPTIONS by Mattt Thompson.
– Basil Bourque
Oct 21 '13 at 21:32
...
What are the differences between a multidimensional array and an array of arrays in C#?
...t32 'value') cil managed
{
// Code size 7 (0x7)
.maxstack 8
IL_0000: ldarg.0
IL_0001: ldarg.1
IL_0002: ldelem.ref
IL_0003: ldarg.2
IL_0004: ldarg.3
IL_0005: stelem.i4
IL_0006: ret
} // end of method Program::SetElementAt
.method private hidebysig static void SetElem...
Why use 'virtual' for class properties in Entity Framework model definitions?
...
It allows the Entity Framework to create a proxy around the virtual property so that the property can support lazy loading and more efficient change tracking. See What effect(s) can the virtual keyword have in Entity Framework 4...
Generate JSON string from NSDictionary in iOS
...ke easier to read).
@interface NSDictionary (BVJSONString)
-(NSString*) bv_jsonStringWithPrettyPrint:(BOOL) prettyPrint;
@end
.
@implementation NSDictionary (BVJSONString)
-(NSString*) bv_jsonStringWithPrettyPrint:(BOOL) prettyPrint {
NSError *error;
NSData *jsonData = [NSJSONSerial...
UIGestureRecognizer on UIImageView
...nEnabled = YES;
UIPinchGestureRecognizer *pgr = [[UIPinchGestureRecognizer alloc]
initWithTarget:self action:@selector(handlePinch:)];
pgr.delegate = self;
[imageView addGestureRecognizer:pgr];
[pgr release];
:
:
- (void)handlePinch:(UIPinchGestureRecognizer *)pinchGestureRecognizer
{
//handl...
Parse email content from quoted reply
...il from any quoted reply text that it might include. I've noticed that usually email clients will put an "On such and such date so and so wrote" or prefix the lines with an angle bracket. Unfortunately, not everyone does this. Does anyone have any idea on how to programmatically detect reply text...
How to export collection to CSV in MongoDB?
How do you export all the records in a MongoDB collection to a .csv file?
11 Answers
...