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Useful information The very beginning of the text field text: let startPosition: UITextPosition = textView.beginningOfDocument The very end of the text field text: let endPosition: UITextPosition = textView.endOfDocument The currently selected range: let selectedRange: UITextRange? = textV...

Test methods often need data to be tested with. To test some methods completely you need to provide different data sets for every possible test condition. Of course, you can do it manually using loops, like this: ... public function testSomething() { $data = [...]; foreach($data as $dat...

Below is an example of a pure Xamarin Forms custom control. No custom rendering is being done for this but could easily be implemented, in fact, in my own code, I use this very same control along with a custom renderer for both the Label and Entry. The custom control is a ContentView with a Label, ...

There are a couple of default recognizers available in Xamarin.Forms, one of them is the TapGestureRecognizer. You can add them to virtually any visual element. Have a look at a simple implementation which binds to an Image. Here is how to do it in code. var tappedCommand = new Command(() => {...

In order to make an Image (or any other visual element) zoomable we have to add a PinchGestureRecognizer to it. Here is how to do it in code: var pinchGesture = new PinchGestureRecognizer(); pinchGesture.PinchUpdated += (s, e) => { // Handle the pinch }; image.GestureRecognizers.Add(pi...

When you have a zoomed Image (or other content) you may want to drag around the Image to show all of its content in the zoomed in state. This can be achieved by implementing the PanGestureRecognizer. From code this looks like so: var panGesture = new PanGestureRecognizer(); panGesture.PanUpdated...

You can simply use the native map APIs on each platform with Xamarin Forms. All you need is to download the Xamarin.Forms.Maps package from nuget and install it to each project (including the PCL project). Maps Initialization First of all you have to add this code to your platform-specific project...

IPython has two parts to it: A command line interface that replaces the default python REPL and a way to run Python through the web browser as a graphical user interface. With the latest developments the browser part has been split into the Jupyter project that enables multiple programming language...

The System.String.Trim method can be used to remove all leading and trailing white-space characters from a string: string s = " String with spaces at both ends "; s = s.Trim(); // s = "String with spaces at both ends" In addition: To remove white-space only fro...

Using the System.String.Replace method, you can replace part of a string with another string. string s = "Hello World"; s = s.Replace("World", "Universe"); // s = "Hello Universe" All the occurrences of the search string are replaced: string s = "He...

Use the System.String.Split method to return a string array that contains substrings of the original string, split based on a specified delimiter: string sentence = "One Two Three Four"; string[] stringArray = sentence.Split(' '); foreach (string word in stringArray) { Console.W...

A few most salient variants: Below 100 import Data.List ( (\\) ) ps100 = ((([2..100] \\ [4,6..100]) \\ [6,9..100]) \\ [10,15..100]) \\ [14,21..100] -- = (((2:[3,5..100]) \\ [9,15..100]) \\ [25,35..100]) \\ [49,63..100] -- = (2:[3,5..100]) \\ ([9,15..100] ++ [25,35..100] ++ [49,63..1...

In some cases we need to apply functions to a set of ND-arrays. Let's look at this simple example. A(:,:,1) = [1 2; 4 5]; A(:,:,2) = [11 22; 44 55]; B(:,:,1) = [7 8; 1 2]; B(:,:,2) = [77 88; 11 22]; A = ans(:,:,1) = 1 2 4 5 ans(:,:,2) = 11 22 44 55 >&...

Let's look at a sample of logging which you can see in many programs: public class LoggingComplex { private static final Logger logger = Logger.getLogger(LoggingComplex.class.getName()); private int total = 50, orders = 20; private String username = "Bob";...

The %s conversion of printf states that the corresponding argument a pointer to the initial element of an array of character type. A null pointer does not point to the initial element of any array of character type, and thus the behavior of the following is undefined: char *foo = NULL; printf(&quo...

Define Interface public interface ClickHandler { public void onButtonClick(User user); } Create Model class public class User { private String name; public User(String name) { this.name = name; } public String getName() { return name; } ...

With this example, you will be able to perform following operations: Connect to Firebase Storage Create a directory named “images” Upload a file in images directory Download a file from images directory Delete a file from images directory public class MainActivity extends AppCompatActivity...

Thanks to type-inference and partial application in F# data-driven programming is succinct and readable. Let's imagine we are selling car insurance. Before we try selling it to a customer, we try to determine if the customer is a valid potential customer for our company by checking the customer's ...

private boolean unpackZip(String path, String zipname){ InputStream is; ZipInputStream zis; try { String filename; is = new FileInputStream(path + zipname); zis = new ZipInputStream(new BufferedInputStream(is)); ZipEntry ze; byte[] buffer = new...

Starting from a dataframe df: U L 111 en 112 en 112 es 113 es 113 ja 113 zh 114 es Imagine you want to add a new column called S taking values from the following dictionary: d = {112: 'en', 113: 'es', 114: 'es', 111: 'en'} You can use map to perform a lookup on keys returni...