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Load an image, decode it into a bitmap, and display the bitmap in an ImageView (or any other view which implements the ImageAware interface): ImageLoader.getInstance().displayImage(imageUri, imageView); Load an image, decode it into a bitmap, and return the bitmap to a callback: ImageLo...

Haskell has list comprehensions, which are a lot like set comprehensions in math and similar implementations in imperative languages such as Python and JavaScript. At their most basic, list comprehensions take the following form. [ x | x <- someList ] For example [ x | x <- [1..4] ] -...

Using the Story Board: Select the tab bar item from the corresponding view controller and go to the attributes inspector If you want a built-in icon and title, set the 'System Item' to the corresponding value. For a custom icon, add the required images to the assets folder and set the 'System It...

If you need an ActiveRecord method to raise an exception instead of a false value in case of failure, you can add ! to them. This is very important. As some exceptions/failures are hard to catch if you don't use ! on them. I recommended doing this in your development cycle to write all your ActiveRe...

You can find records by any field in your table using find_by. So, if you have a User model with a first_name attribute you can do: User.find_by(first_name: "John") #=> #<User id: 2005, first_name: "John", last_name: "Smith"> Mind that find_by doesn't thr...

Break multiple loop: arr=(a b c d e f) for i in "${arr[@]}";do echo "$i" for j in "${arr[@]}";do echo "$j" break 2 done done Output: a a Break single loop: arr=(a b c d e f) for i in "${arr[@]}";do e...

You can send a block to your method and it can call that block multiple times. This can be done by sending a proc/lambda or such, but is easier and faster with yield: def simple(arg1,arg2) puts "First we are here: #{arg1}" yield puts "Finally we are here: #{arg2}" ...

Symbol is a new primitive type in ES6. Symbols are used mainly as property keys, and one of its main characteristics is that they are unique, even if they have the same description. This means they will never have a name clash with any other property key that is a symbol or string. const MY_PROP_KE...

Let's assume that we want to remove 2 upvotes from all the articles of the author with id 51. Doing this only with Python would execute N queries (N being the number of articles in the queryset): for article in Article.objects.filter(author_id=51): article.upvotes -= 2 article.save() ...

// You need a writable database to update a row final SQLiteDatabase database = openHelper.getWritableDatabase(); // Create a ContentValues instance which contains the up to date data for each column // Unlike when inserting data you need to specify the value for the PRIMARY KEY column as well ...

Go to File -> Settings -> Editor -> Colors & Fonts -> Android Logcat Change the colors as you need: Choose the appropriate color:

Some basic types and classes in Java are fundamentally mutable. For example, all array types are mutable, and so are classes like java.util.Data. This can be awkward in situations where an immutable type is mandated. One way to deal with this is to create an immutable wrapper for the mutable type...

static int Sum(int a, int b) { return a + b; } static int Multiplication(int a, int b) { return a * b; } static void Main(string[] args) { Func<int, int, int> method = Sum; // method points to the Sum method // that retuns 1 int variable and takes 2 int vari...

An anonymous method can be assigned wherever a delegate is expected: Func<int, int> square = delegate (int x) { return x * x; } Lambda expressions can be used to express the same thing: Func<int, int> square = x => x * x; In either case, we can now invoke the method stored ins...

An immutable object is an object whose state cannot be changed. An immutable class is a class whose instances are immutable by design, and implementation. The Java class which is most commonly presented as an example of immutability is java.lang.String. The following is a stereotypical example: ...

A boolean represents the most basic datatype in TypeScript, with the purpose of assigning true/false values. // set with initial value (either true or false) let isTrue: boolean = true; // defaults to 'undefined', when not explicitely set let unsetBool: boolean; // can ...

Like JavaScript, numbers are floating point values. let pi: number = 3.14; // base 10 decimal by default let hexadecimal: number = 0xFF; // 255 in decimal ECMAScript 2015 allows binary and octal. let binary: number = 0b10; // 2 in decimal let octal: number = 0o755; // 493 in de...

Number formatting, grouping digits according to the localization. const usNumberFormat = new Intl.NumberFormat('en-US'); const esNumberFormat = new Intl.NumberFormat('es-ES'); const usNumber = usNumberFormat.format(99999999.99); // "99,999,999.99" const esNumber = esNumberFormat.form...

To convert decimal number to binary format use base 2 Int32 Number = 15; Console.WriteLine(Convert.ToString(Number, 2)); //OUTPUT : 1111 To convert decimal number to octal format use base 8 int Number = 15; Console.WriteLine(Convert.ToString(Number, 8)); //OUTPUT : 17 To conv...

The most feasible way is to use, the DateTime class. An example: <?php // Create a date time object, which has the value of ~ two years ago $twoYearsAgo = new DateTime("2014-01-18 20:05:56"); // Create a date time object, which has the value of ~ now $now = new DateTime("2016...