Tutorial by Examples: l

Load HTML string

Web views are useful to load locally generated HTML strings. NSString *html = @"<!DOCTYPE html><html><body>Hello World</body></html>"; [webView loadHTMLString:html baseURL:nil]; Swift let htmlString = "<h1>My First Heading</h1><p&gt...

Standard form vs Elvis form

// long form String sayHello(String name){ "Hello, ${name ? name : 'stranger'}." } // elvis String sayHello(String name){ "Hello, ${name ?: 'stranger'}." } Notice that the "elvis" format omits the "true" term because the original comparison...

Installing R

You might wish to install RStudio after you have installed R. RStudio is a development environment for R that simplifies many programming tasks. Windows only: Visual Studio (starting from version 2015 Update 3) now features a development environment for R called R Tools, that includes a live inter...

Creating a UIBarButtonItem in the Interface Builder

The example below shows how to add a navigation bar button (called a UIBarButtonItem) in the Interface Builder. Add a Navigation Controller to your Storyboard Select your View Controller and then in the Xcode menu choose Editor > Embed In > Navigation Controller. Alternatively, you could ...

Create an Xamarin Forms custom input control (no native required)

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, ...

Make an Image tappable by adding a TapGestureRecognizer

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(() => {...

Show all of the zoomed Image content with the PanGestureRecognizer

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...

Basic Binding to ViewModel

EntryPage.xaml: <?xml version="1.0" encoding="utf-8" ?> <ContentPage xmlns="http://xamarin.com/schemas/2014/forms" xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml" xmlns:vm="clr-namespace:MyAssembly.ViewModel;a...

Valid Keys

Redis keys are binary-safe, so literally anything can be used as a key. The only limitations are that they must be less than 512MB. Examples of valid keys: 7 ++++ `~!@#$%^&*()-_=+ user:10134 search/9947372/?query=this%20is%20a%28test%29%20query <div id="div64"> Any othe...

Replacing a string within a string

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...

Splitting a string using a delimiter

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...

Concatenate an array of strings into a single string

The System.String.Join method allows to concatenate all elements in a string array, using a specified separator between each element: string[] words = {"One", "Two", "Three", "Four"}; string singleString = String.Join(",", words); // singleString =...

rearrange a ND-array may improve the overall performance

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 >&...

Logging complex messages (efficiently)

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";...

Custom colour and line style orders

In MATLAB, we can set new default custom orders, such as a colour order and a line style order. That means new orders will be applied to any figure that is created after these settings have been applied. The new settings remains until MATLAB session is closed or new settings has been made. Default ...

How to add Facebook Login in Android

Add below dependencies to your build.gradle // Facebook login compile 'com.facebook.android:facebook-android-sdk:4.21.1' Add below helper class to your utility package: /** * Created by Andy * An utility for Facebook */ public class FacebookSignInHelper { private static final...

Passing a null pointer to printf %s conversion

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...

Click listener with Binding

Create interface for clickHandler public interface ClickHandler { public void onButtonClick(View v); } Layout XML <?xml version="1.0" encoding="utf-8"?> <layout xmlns:android="http://schemas.android.com/apk/res/android"> <data> ...

Custom event using lambda expression

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; } ...

Unzip file

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...

Page 332 of 861

logo rip
SUPPORT & PARTNERS
STAY CONNECTED

Get monthly updates about new articles, cheatsheets, and tricks.