Tutorial by Examples: u

The following program: class Program { static void Method(params Object[] objects) { System.Console.WriteLine(objects.Length); } static void Method(Object a, Object b) { System.Console.WriteLine("two"); } static void Main(string[] a...

The following examples will not compile: string s = "\c"; char c = '\c'; Instead, they will produce the error Unrecognized escape sequence at compile time.

NumberFormatInfo can be used for formatting both integer and float numbers. // invariantResult is "1,234,567.89" var invarianResult = string.Format(CultureInfo.InvariantCulture, "{0:#,###,##}", 1234567.89); // NumberFormatInfo is one of classes that implement IFormatProvider...

The nameof operator allows you to get the name of a variable, type or member in string form without hard-coding it as a literal. The operation is evaluated at compile-time, which means that you can rename, using an IDE's rename feature, a referenced identifier and the name string will update with it...

Snippet Console.WriteLine(nameof(CompanyNamespace.MyNamespace)); Console.WriteLine(nameof(MyClass)); Console.WriteLine(nameof(MyClass.MyNestedClass)); Console.WriteLine(nameof(MyNamespace.MyClass.MyNestedClass.MyStaticProperty)); Console Output MyNamespace MyClass MyNestedClass MyStatic...

Create a property with getter and/or setter and initialize all in one line: public string Foobar { get; set; } = "xyz";

class Example { public string Foobar { get; set; } public List<string> Names { get; set; } public Example() { Foobar = "xyz"; Names = new List<string>(){"carrot","fox","ball"}; } }

Create a new file in your text editor or IDE named HelloWorld.java. Then paste this code block into the file and save: public class HelloWorld { public static void main(String[] args) { System.out.println("Hello, World!"); } } Run live on Ideone Note: For Java to r...

A Stream is a sequence of elements upon which sequential and parallel aggregate operations can be performed. Any given Stream can potentially have an unlimited amount of data flowing through it. As a result, data received from a Stream is processed individually as it arrives, as opposed to performin...

Sorting lists Prior to Java 8, it was necessary to implement the java.util.Comparator interface with an anonymous (or named) class when sorting a list1: Java SE 1.2 List<Person> people = ... Collections.sort( people, new Comparator<Person>() { public int compare(Pe...

The LinearLayout is a ViewGroup that arranges its children in a single column or a single row. The orientation can be set by calling the method setOrientation() or using the xml attribute android:orientation. Vertical orientation : android:orientation="vertical" <?xml version=&quo...

RelativeLayout is a ViewGroup that displays child views in relative positions. By default, all child views are drawn at the top-left of the layout, so you must define the position of each view using the various layout properties available from RelativeLayout.LayoutParams. The value for each layout...

This is an example of a default build.gradle file in a module. apply plugin: 'com.android.application' android { compileSdkVersion 25 buildToolsVersion '25.0.3' signingConfigs { applicationName { keyAlias 'applicationName' keyPassword 'password...

android:layout_gravity android:layout_gravity is used to set the position of an element in its parent (e.g. a child View inside a Layout). Supported by LinearLayout and FrameLayout android:gravity android:gravity is used to set the position of content inside an element (e.g. a text insid...

GridLayout, as the name suggests is a layout used to arrange Views in a grid. A GridLayout divides itself into columns and rows. As you can see in the example below, the amount of columns and/or rows is specified by the properties columnCount and rowCount. Adding Views to this layout will add the fi...

Product flavors are defined in the build.gradle file inside the android { ... } block as seen below. ... android { ... productFlavors { free { applicationId "com.example.app.free" versionName "1.0-free" } paid { ...

Dependencies can be added for a specific product flavor, similar to how they can be added for specific build configurations. For this example, assume that we have already defined two product flavors called free and paid (more on defining flavors here). We can then add the AdMob dependency for the ...

Resources can be added for a specific product flavor. For this example, assume that we have already defined two product flavors called free and paid. In order to add product flavor-specific resources, we create additional resource folders alongside the main/res folder, which we can then add resourc...

A Java class can implement multiple interfaces. public interface NoiseMaker { String noise = "Making Noise"; // interface variables are public static final by default String makeNoise(); //interface methods are public abstract by default } public interface FoodEater { ...

We can use V put(K key,V value): Associates the specified value with the specified key in this map (optional operation). If the map previously contained a mapping for the key, the old value is replaced by the specified value. String currentVal; Map<Integer, String> map = new TreeMap&l...