Tutorial by Examples: d

Add the following pom to the dependencies section of your gradle build file : project.dependencies { compile 'org.roboguice:roboguice:3.+' provided 'org.roboguice:roboblender:3.+' }

The UIAlertController available since iOS8 allows you to use the same alert object for either Action sheets or more classic alerts. The only difference is the UIAlertControllerStyle passed as a parameter when creating. This line changes from an AlertView to an ActionSheet, compared to some other ex...

It was common practice to use NSRunLoop to show modal UIAlertView to block code execution until user input is processed in iOS; until Apple released the iOS7, it broke few existing apps. Fortunately, there is a better way of implementing it with C#’s async/await. Here’s the new code taking advantag...

User input Imagine you want a user to enter a number via input. You want to ensure that the input is a number. You can use try/except for this: Python 3.x3.0 while True: try: nb = int(input('Enter a number: ')) break except ValueError: print('This is not a num...

To change the appearance of the keyboard, the following types can be set individually on every UITextFields property: keyboardType typedef NS_ENUM(NSInteger, UIKeyboardType) { UIKeyboardTypeDefault, // Default type for the current input method. UIKeyboardTypeASCIICapable, ...

Func provides a holder for parameterised anonymous functions. The leading types are the inputs and the last type is always the return value. // square a number. Func<double, double> square = (x) => { return x * x; }; // get the square root. // note how the signature matches the built ...

Functions have two built-in methods that allow the programmer to supply arguments and the this variable differently: call and apply. This is useful, because functions that operate on one object (the object that they are a property of) can be repurposed to operate on another, compatible object. Addi...

DECLARE @Employees TABLE ( EmployeeID INT NOT NULL PRIMARY KEY, FirstName NVARCHAR(50) NOT NULL, LastName NVARCHAR(50) NOT NULL, ManagerID INT NULL ) When you create a normal table, you use CREATE TABLE Name (Columns) syntax. When creating a table variable, you use DECLARE @...

DECLARE @VariableName INT SET @VariableName = 1 PRINT @VariableName 1 Using SET, you can only update one variable at a time.

Using SELECT, you can update multiple variables at once. DECLARE @Variable1 INT, @Variable2 VARCHAR(10) SELECT @Variable1 = 1, @Variable2 = 'Hello' PRINT @Variable1 PRINT @Variable2 1 Hello When using SELECT to update a variable from a table column, if there are multiple values, it wi...

DECLARE @Var1 INT = 5, @Var2 NVARCHAR(50) = N'Hello World', @Var3 DATETIME = GETDATE()

This is an example of what a simple Arduino sketch looks like after being imported into Atmel Studio. Atmel Studio added the auto generated sections at the top. The rest is identical to the original Arduino code. If you expand the ArduinoCore project that was created and look in the src -> cor...

You can group related assertions in deftest unit tests within a context using the testing macro: (deftest add-nums (testing "Positive cases" (is (= 2 (+ 1 1))) (is (= 4 (+ 2 2)))) (testing "Negative cases" (is (= -1 (+ 2 -3))) (is (= -4 (+ 8 -12))))) ...

deftest is a macro for defining a unit test, similar to unit tests in other languages. You can create a test as follows: (deftest add-nums (is (= 2 (+ 1 1))) (is (= 3 (+ 1 2)))) Here we are defining a test called add-nums, which tests the + function. The test has two assertions. You can ...

Let's say we wish to write Euclid's gcd() as a lambda. As a function, it is: int gcd(int a, int b) { return b == 0 ? a : gcd(b, a%b); } But a lambda cannot be recursive, it has no way to invoke itself. A lambda has no name and using this within the body of a lambda refers to a captured thi...

int a = 6; // 0110b (0x06) int b = 10; // 1010b (0x0A) int c = a & b; // 0010b (0x02) std::cout << "a = " << a << ", b = " << b << ", c = " << c << std::endl; Output a = 6, b = 10, c = 2 Why A bit wise A...

The Windows API is provided by means of a C-callable interface. Success or failure of an API call is reported strictly through return values. Exceptions aren't part of the documented contract (although some API implementations can raise SEH exceptions, e.g. when passing a read-only lpCommandLine arg...

Some API calls return a single failure/success flag, without any additional information (e.g. GetObject): if ( GetObjectW( obj, 0, NULL ) == 0 ) { // Failure: no additional information available. }

In addition to a failure/success return value, some API calls also set the last error on failure (e.g. CreateWindow). The documentation usually contains the following standard wording for this case: If the function succeeds, the return value is <API-specific success value>. If the function...

Some API calls can succeed or fail in more than one way. The APIs commonly return additional information for both successful invocations as well as errors (e.g. CreateMutex). if ( CreateMutexW( NULL, TRUE, L"Global\\MyNamedMutex" ) == NULL ) { // Failure: get additional information. ...