Tutorial by Examples: g

NSDictionary *inventory = [NSDictionary dictionaryWithObjectsAndKeys: [NSNumber numberWithInt:13], @"Mercedes-Benz SLK250", [NSNumber numberWithInt:22], @"Mercedes-Benz E350", [NSNumber numberWithInt:19], @"BMW M3 Coupe", [NSNumber numberWithInt:16],...

To combine an NSArray of NSString into a new NSString: NSArray *yourWords = @[@"Objective-C", @"is", @"just", @"awesome"]; NSString *sentence = [yourWords componentsJoinedByString:@" "]; // Sentence is now: @"Objective-C is just awesome&quo...

You can open the VB editor in any of the Microsoft Office applications by pressing Alt+F11 or going to the Developer tab and clicking on the "Visual Basic" button. If you don't see the Developer tab in the Ribbon, check if this is enabled. By default the Developer tab is disabled. To enab...

Rails provides several ways to organize your routes. Scope by URL: scope 'admin' do get 'dashboard', to: 'administration#dashboard' resources 'employees' end This generates the following routes get '/admin/dashboard', to: 'administration#dashboard' post '/admin/empl...

Example for reading file data_file.csv such as: File: index,header1,header2,header3 1,str_data,12,1.4 3,str_data,22,42.33 4,str_data,2,3.44 2,str_data,43,43.34 7, str_data, 25, 23.32 Code: pd.read_csv('data_file.csv') Output: index header1 header2 header3 0 1 str_dat...

On most GNU+Linux operating systems, PostgreSQL can easily be installed using the operating system package manager. Red Hat family Respositories can be found here: https://yum.postgresql.org/repopackages.php Download the repository to local machine with the command yum -y install https://downloa...

Models are typically defined in the models.py file under your application subdirectory. The Model class of django.db.models module is a good starting class to extend your models from. For example: from django.db import models class Book(models.Model): title = models.CharField(max_length=100...

Once your virtual environment has been activated, any package that you install will now be installed in the virtualenv & not globally. Hence, new packages can be without needing root privileges. To verify that the packages are being installed into the virtualenv run the following command to che...

Assuming python and python3 are both installed, it is possible to create a virtual environment for Python 3 even if python3 is not the default Python: virtualenv -p python3 foo or virtualenv --python=python3 foo or python3 -m venv foo or pyvenv foo Actually you can create virtual ...

The method nextInt(int bound) of Random accepts an upper exclusive boundary, i.e. a number that the returned random value must be less than. However, only the nextInt method accepts a bound; nextLong, nextDouble etc. do not. Random random = new Random(); random.nextInt(1000); // 0 - 999 int num...

NSArray *array = [NSArray arrayWithObjects:@"Nick", @"Ben", @"Adam", @"Melissa", nil]; NSPredicate *aPredicate = [NSPredicate predicateWithFormat:@"SELF beginswith[c] 'a'"]; NSArray *beginWithA = [array filteredArrayUsingPredicate:bPredicate]; ...

Getting ("a", 1) ^. _1 -- returns "a" ("a", 1) ^. _2 -- returns 1 Setting ("a", 1) & _1 .~ "b" -- returns ("b", 1) Modifying ("a", 1) & _2 %~ (+1) -- returns ("a", 2) both Traversal (1, 2) & bot...

Requirements: Installed Java JDK or JRE (version 7 or higher for Gradle 3.x version) Installation steps: Download Gradle distribution from the official web site Unpack the ZIP Add the GRADLE_HOME environment variable. This variable should point to the unpacked files from the previous step. Ad...

First of all, implement your view holder: implements View.OnClickListener, View.OnLongClickListener Then, register the listeners as follows: itemView.setOnClickListener(this); itemView.setOnLongClickListener(this); Next, override the listeners as follows: @Override public void onClick(Vie...

By default error message appears below textbox in <div class="help-block"></div> on keyUp or after pressing submit button if any validation constraints aren't met. Sometimes we want a message on submit only i.e. no validation at onKeyup event. Let's check yii2/widgets/ActiveF...

// decode NSString *string = [[NSString alloc] initWithData:utf8Data encoding:NSUTF8StringEncoding]; // encode NSData *utf8Data = [string dataUsingEncoding:NSUTF8StringEncoding]; Some supported encodings are: NSASCIIStringEncoding NSUTF8StringEnc...

The first step to start Xamarin development on an OS X machine, is to download and install Xamarin Studio Community version from the official website. A few fields need to be filled to download the installer as shown in the picture below. The Xamarin Unified installer takes care of identifying an...

There are several ways methods can be inherited public abstract class Car { public void HonkHorn() { // Implementation of horn being honked } // virtual methods CAN be overridden in derived classes public virtual void ChangeGear() { // Implementation of gear...

All java Collection<E>s have stream() and parallelStream() methods from which a Stream<E> can be constructed: Collection<String> stringList = new ArrayList<>(); Stream<String> stringStream = stringList.parallelStream(); A Stream<E> can be created from an arra...

You don't have to check the IDisposable object for null. using will not throw an exception and Dispose() will not be called: DisposableObject TryOpenFile() { return null; } // disposable is null here, but this does not throw an exception using (var disposable = TryOpenFile()) { //...