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If you want to show local notification immediately, you should call: Swift 3 UIApplication.shared.presentLocalNotificationNow(notification) Swift 2 UIApplication.sharedApplication().presentLocalNotificationNow(notification) Objective-C [[UIApplication sharedApplication] presentLocalNotific...

Create a new console application with one line in the Main method: Console.WriteLine("Hello World") Remember the path to the .csproj file and replace it in the example. Create a new Console Application and install the Microsoft.CodeAnalysis NuGet package and try the following code: cons...

Create a new console application with one line in the Main method: Console.WriteLine("Hello World") Remember the path to the .vbproj file and replace it in the example. Create a new Console Application and install the Microsoft.CodeAnalysis NuGet package and try the following code: Cons...

In general, IBOutlets are used to connect an user interface object to another object, in this case a UIViewController. The connection serves to allow for the object to be affected my code or events programmatically. This can be done simply by using the assistant from a storyboard and control-clickin...

The following example is a sample Less file which shows how variables are declared and used, how mixins are defined and called in Less. /* Variables */ @color-base: #87ceeb; /* Simple mixin to set border */ .set-border(@width; @style; @color) { border: @width @style darken(@color, 10%); ...

In F# there are many options for creating data pipelines, for example: List, Seq and Array. What data pipeline is preferable from memory usage and performance perspective? In order to answer this we'll compare performance and memory usage using different pipelines. Data Pipeline In order to me...

By adding the following extension to array indices can be accessed without knowing if the index is inside bounds. extension Array { subscript (safe index: Int) -> Element? { return indices ~= index ? self[index] : nil } } example: if let thirdValue = array[safe: 2] { ...

Labeling the alternatives inside a rule starting with the # operator tells ANTLR to generate listener methods for each label corresponding to the alternative. By specifying a label for each alternative in the following rule: // Rule type : int #typeInt | short #typeShort | long ...

Add the following code to the onCreate()/onResume() method: SensorManager sensorManager; Sensor mAccelerometer; final float movementThreshold = 0.5f; // You may have to change this value. boolean isMoving = false; float[] prevValues = {1.0f, 1.0f, 1.0f}; float[] currValues = new float[3]; ...

string path = @"c:\path\to\file.txt"; File.Delete(path); While Delete does not throw exception if file doesn't exist, it will throw exception e.g. if specified path is invalid or caller does not have the required permissions. You should always wrap calls to Delete inside try-catch bloc...

Having more than one element with the same ID is a hard to troubleshoot problem. The HTML parser will usually try to render the page in any case. Usually no error occurs. But the pace could end up in a mis-behaving web page. In this example: <div id="aDiv">a</div> <div id...

Selectors are used as method identifiers in Objective-C. In the example below, there are two selectors. new and setName: Person* customer = [Person new]; [customer setName:@"John Doe"]; Each pair of brackets corresponds to a message send. On the first line we send a message containin...

Given 2 lists var list1 = new List<string> { "a", "b", "c" }; var list2 = new List<string> { "1", "2", "3", "4" }; if you want to output all permutations you could use nested loops like var result = new List<s...

C++11 The std::is_same<T, T> type relation is used to compare two types. It will evaluate as boolean, true if the types are the same and false if otherwise. e.g. // Prints true on most x86 and x86_64 compilers. std::cout << std::is_same<int, int32_t>::value << "\n&qu...

There have been many releases of Java since the original Java 1.0 release in 1995. (Refer to Java version history for a summary.) However most releases have passed their official End Of Life dates. This means that the vendor (typically Oracle now) has ceased new development for the release, and n...

One method for creating recursive lambda functions involves assigning the function to a variable and then referencing that variable within the function itself. A common example of this is the recursive calculation of the factorial of a number - such as shown in the following code: lambda_factorial ...

Sometimes it's useful to check if a field is present or absent on your JSON to avoid some JSONException on your code. To achieve that, use the JSONObject#has(String) or the method, like on the following example: Sample JSON { "name":"James" } Java code String jsonStr...

Java release naming is a little confusing. There are actually two systems of naming and numbering, as shown in this table: JDK versionMarketing namejdk-1.0JDK 1.0jdk-1.1JDK 1.1jdk-1.2J2SE 1.2......jdk-1.5J2SE 1.5 rebranded Java SE 5jdk-1.6Java SE 6jdk-1.7Java SE 7jdk-1.8Java SE 8jdk-91Java SE 9 (n...

The following function finds the maximal element in an array: int find_max(const int *array, size_t len) { int max = INT_MIN; for (size_t i = 0; i < len; i++) { if (max < array[i]) { max = array[i]; } } return max; } The input size is the...

Ordering directly on JSONField is not yet supported in Django. But it's possible via RawSQL using PostgreSQL functions for jsonb: from django.db.models.expressions import RawSQL RatebookDataEntry.objects.all().order_by(RawSQL("data->>%s", ("json_objects_key",))) This e...