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CSS3 introduces a few new units, including the rem unit, which stands for "root em". Let's look at how rem works. First, let's look at the differences between em and rem. em: Relative to the font size of the parent. This causes the compounding issue rem: Relative to the font size of t...

If value types are assigned to variables of type object they are boxed - the value is stored in an instance of a System.Object. This can lead to unintended consequences when comparing values with ==, e.g.: object left = (int)1; // int in an object box object right = (int)1; // int in an object bo...

Boxed value types can only be unboxed into their original Type, even if a conversion of the two Types is valid, e.g.: object boxedInt = (int)1; // int boxed in an object long unboxedInt1 = (long)boxedInt; // invalid cast This can be avoided by first unboxing into the original Type, e.g.: lon...

This example shows how to check permissions at runtime in Android 6 and later. public static final int MULTIPLE_PERMISSIONS = 10; // code you want. String[] permissions = new String[] { Manifest.permission.WRITE_EXTERNAL_STORAGE, Manifest.permission.CAMERA, Manifest.permission.ACC...

Create a circle image with glide. public class CircleTransform extends BitmapTransformation { public CircleTransform(Context context) { super(context); } @Override protected Bitmap transform(BitmapPool pool, Bitmap toTransform, int outWidth, int outHeight) { ret...

All C functions are in actuality pointers to a spot in the program memory where some code exists. The main use of a function pointer is to provide a "callback" to other functions (or to simulate classes and objects). The syntax of a function, as defined further down on this page is: retu...

function foo() { console.trace('My log statement'); } foo(); Will display this in the console: My log statement VM696:1 foo @ VM696:1 (anonymous function) @ (program):1 Note: Where available it's also useful to know that the same stack trace is accessible a...

public static void Main() { var xml = new XmlDocument(); var root = xml.CreateElement("element"); // Creates an attribute, so the element will now be "<element attribute='value' />" root.SetAttribute("attribute", "value"); ...

In Python 2, an octal literal could be defined as >>> 0755 # only Python 2 To ensure cross-compatibility, use 0o755 # both Python 2 and Python 3

NSDictionary *myDictionary = [[NSDictionary alloc] initWithObjectsAndKeys:@"value1", @"key1", @"value2", @"key2", nil]; NSArray *copiedArray = myDictionary.copy; Get keys: NSArray *keys = [myDictionary allKeys]; Get values: NSArray *values = [myDic...

NSDictionary *myDictionary = [[NSDictionary alloc] initWithObjectsAndKeys:@"value1", @"key1", @"value2", @"key2", nil]; NSData *myData = [NSKeyedArchiver archivedDataWithRootObject:myDictionary]; Reserve path: NSDictionary *myDictionary = (NSDictionary*...

NSDictionary *myDictionary = [[NSDictionary alloc] initWithObjectsAndKeys:@"value1", @"key1", @"value2", @"key2", nil]; NSMutableDictionary *mutableDictionary = [myDictionary mutableCopy]; NSData *data = [NSJSONSerialization dataWithJSONObject:myDiction...

Swift import SystemConfiguration /// Class helps to code reuse in handling internet network connections. class NetworkHelper { /** Verify if the device is connected to internet network. - returns: true if is connected to any internet network, false if is not co...

The random number generator can (and should) be used for multiple distributions. #include <iostream> #include <random> int main() { std::default_random_engine pseudo_random_generator; std::uniform_int_distribution<int> int_distribution(0, 9); std::uniform_real_dis...

//Swift let barButtonItem = UIBarButtonItem(title: "Greetings!", style: .Plain, target: self, action: #selector(barButtonTapped)) self.navigationItem.rightBarButtonItem = barButtonItem //Objective-C UIBarButtonItem *barButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"Greeti...

Define a new type Person using namedtuple like this: Person = namedtuple('Person', ['age', 'height', 'name']) The second argument is the list of attributes that the tuple will have. You can list these attributes also as either space or comma separated string: Person = namedtuple('Person', 'age,...

Exceptions are errors which occur when a program is executing. Consider the Java program below which divides two integers. class Division { public static void main(String[] args) { int a, b, result; Scanner input = new Scanner(System.in); System.out.println(&qu...

NSSet *set = [NSSet set]; NSArray *array = [NSArray array]; NSArray *fromSet = [set allObjects]; NSSet *fromArray = [NSSet setWithArray:array];

IMPORTANT: This delegate method is only called in the foreground. Swift func application(application: UIApplication, didReceiveLocalNotification notification: UILocalNotification) { } Objective-C - (void)application:(UIApplication *)application didReceiveLocalNotification:(UILocalNotifi...

Function DisableShift() 'This function disable the shift at startup. This action causes 'the Autoexec macro and Startup properties to always be executed. On Error GoTo errDisableShift Dim db As DAO.Database Dim prop As DAO.Property Const conPropNotFound = 3270 Set db = C...