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iOS: How to store username/password within an app?
... of this class:
KeychainItemWrapper *keychainItem = [[KeychainItemWrapper alloc] initWithIdentifier:@"YourAppLogin" accessGroup:nil];
(YourAppLogin can be anything you chose to call your Keychain item and you can have multiple items if required)
Then you can set the username and password using:
...
How do I profile memory usage in Python?
...
Python 3.4 includes a new module: tracemalloc. It provides detailed statistics about which code is allocating the most memory. Here's an example that displays the top three lines allocating memory.
from collections import Counter
import linecache
import os
import ...
Why start an ArrayList with an initial capacity?
...ity. If you don't do this, the internal array will have to be repeatedly reallocated as the list grows.
The larger the final list, the more time you save by avoiding the reallocations.
That said, even without pre-allocation, inserting n elements at the back of an ArrayList is guaranteed to take to...
How does the NSAutoreleasePool autorelease pool work?
As I understand it, anything created with an alloc , new , or copy needs to be manually released. For example:
7 Answer...
Optimising Android application before release [closed]
...
Track and squash allocations. The more you allocate, the more often the garbage collector will need to run, stopping your process from doing anything else for relatively long periods of time, such as 100ms or so.
The best tool I know for th...
How to show “Done” button on iPhone number pad
...oad
{
[super viewDidLoad];
UIToolbar* numberToolbar = [[UIToolbar alloc]initWithFrame:CGRectMake(0, 0, 320, 50)];
numberToolbar.barStyle = UIBarStyleBlackTranslucent;
numberToolbar.items = @[[[UIBarButtonItem alloc]initWithTitle:@"Cancel" style:UIBarButtonItemStyleBordered target:se...
What happens when a computer program runs?
... but modern OSes with virtual memory tend to load their process images and allocate memory something like this:
+---------+
| stack | function-local variables, return addresses, return values, etc.
| | often grows downward, commonly accessed via "push" and "pop" (but can be
| | ...
Animate change of view controllers without using navigation controller stack, subviews or modal cont
...ngWithOptions:(NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
MyViewController *vc = [[MyViewContoller alloc] init...];
self.transitionController = [[TransitionController alloc] initWithViewController:vc];
self.window.roo...
What are the differences between Rust's `String` and `str`?
...he executable and loaded into memory when the program runs.
Inside a heap allocated String: String dereferences to a &str view of the String's data.
On the stack: e.g. the following creates a stack-allocated byte array, and then gets a view of that data as a &str:
use std::str;
let x:...
Stack Memory vs Heap Memory [duplicate]
...thing similar.
Heap memory is much as rskar says. In general, C++ objects allocated with new, or blocks of memory allocated with the likes of malloc end up on the heap. Heap memory almost always must be manually freed, though you should really use a smart pointer class or similar to avoid needing t...