Tutorial by Examples: the

Cryptography is something very hard and after spending a lot of time reading different examples and seeing how easy it is to introduce some form of vulnerability I found an answer originally written by @jbtule that I think is very good. Enjoy reading: "The general best practice for symmetric e...

After the user signed in to Facebook at your app, now it's time to fetch the data you requested at the FBButton.readPermissions. Swift: enum FacebookParametesField : String { case FIELDS_KEY = "fields" case FIELDS_VALUE = "id, email, picture, first_name, last_name" ...

In SpriteKit a Sprite is represented by the SKSpriteNode class (which inherits from SKNode). First of all create a new Xcode Project based on the SpriteKit template as described in Your First SpriteKit Game. Creating a Sprite Now you can create a SKSpriteNode using an image loaded into the Assets...

From Apple documentation: Use the CTCallCenter class to obtain a list of current cellular calls, and to respond to state changes for calls such as from a dialing state to a connected state. Such state changes are known as cellular call events. The purpose of CTCallCenter is to give the develop...

C-style bit-manipulation // Bit n will be set if x is 1 and cleared if x is 0. number ^= (-x ^ number) & (1LL << n); Using std::bitset set(n,val) - sets bit n to the value val. std::bitset<5> num(std::string("00100")); num.set(0,true); // num is now 00101 num.set(...

All collection objects contain a map method that takes a Function as an argument, which must take a single argument. This returns an Iterable backed by the collection. When the Iterable is iterated, each step calls the function with a new element of the collection, and the result of the call becomes...

mount is used to mount another application (basically rack application) or rails engines to be used within the current application syntax: mount SomeRackApp, at: "some_route" Now you can access above mounted application using route helper some_rack_app_path or some_rack_app_url. But ...

In cases such as restoring a database dump, or otherwise wishing to push some information through a pipe from the host, you can use the -i flag as an argument to docker run or docker exec. E.g., assuming you want to put to a containerized mariadb client a database dump that you have on the host, in...

The aar file doesn't contain the transitive dependencies and doesn't have a pom file which describes the dependencies used by the library. It means that, if you are importing a aar file using a flatDir repo you have to specify the dependencies also in your project. You should use a maven repositor...

The XMPP network can be thought of as a bidirected graph with servers (S) operating in a mesh, clients (C) clustered about their local server, and streams represented by extraverted edges: When a client wants to send data (eg. a message or presence information) across the network to another clien...

The following code can be entered in a Tcl shell (tclsh), or into a script file and run through a Tcl shell: puts "Hello, world!" It gives the string argument Hello, world! to the command puts. The puts command writes its argument to standard out (your terminal in interactive mode) an...

C++11 The type std::conditional in the standard library header <type_traits> can select one type or the other, based on a compile-time boolean value: template<typename T> struct ValueOrPointer { typename std::conditional<(sizeof(T) > sizeof(void*)), T*, T>::type vop; }...

Add a keystore using: keytool -genkey -v -keystore example.keystore -alias example -keyalg RSA -keysize 2048 -validity 10000 Note: This should be at root of project. Though not a hard requirement, it eases the file referencing Add a build.json with release/dev configuration for key...

Meteor.call(name, [arg1, arg2...], [asyncCallback]) (1) name String (2) Name of method to invoke (3) arg1, arg2... EJSON-able Object [Optional] (4) asyncCallback Function [Optional] On one hand, you can do : (via Session variable, or via ReactiveVar) var syncCall = Meteor.call("my...

Surround with Surrounds a code block with an if, for, <editor-fold ...> and more. Windows / Linux: Ctrl + Alt + T OS X / macOS: Cmd + Option + T

When adding content from sources outside your domain, or from the local file system the canvas is marked as tainted. Attempt to access the pixel data, or convert to a dataURL will throw a security error. vr image = new Image(); image.src = "file://myLocalImage.png"; image.onload = funct...

By default the Large Object Heap is not compacted unlike the classic Object Heap which can lead to memory fragmentation and further, can lead to OutOfMemoryExceptions Starting with .NET 4.5.1 there is an option to explicitly compact the Large Object Heap (along with a garbage collection): GCSettin...

XML <Galaxy> <name>Milky Way</name> <CelestialObject name="Earth" type="planet"/> <CelestialObject name="Sun" type="star"/> </Galaxy> XPATH /Galaxy/*[starts-with(lower-case(@name),'ear')] or //*[star...

XML <Galaxy> <name>Milky Way</name> <CelestialObject name="Earth" type="planet"/> <CelestialObject name="Sun" type="star"/> </Galaxy> XPATH /Galaxy/*[ends-with(lower-case(@type),'tar')] or //*[ends-w...

The requests module has top-level functions for most HTTP methods: r = requests.put('https://example.com/', data=put_body) r = requests.delete('https://example.com/') r = requests.head('https://example.com/') r = requests.options('https://example.com/') r = requests.patch('https://example.com/'...