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Put your dbname.sqlite or dbname.db file in assets folder of your project. public class Databasehelper extends SQLiteOpenHelper { public static final String TAG = Databasehelper.class.getSimpleName(); public static int flag; // Exact Name of you db file that you put in as...

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...

The flatMap operator help you to transform one event to another Observable (or transform an event to zero, one, or more events). It's a perfect operator when you want to call another method which return an Observable public Observable<String> perform(int i) { // ... } Observabl...

You can animate complex changes to your collection view using the performBatchUpdates method. Inside the update block, you can specify several modifications to have them animate all at once. collecitonView.performBatchUpdates({ // Perform updates }, nil) Inside the update block, you can pe...

C-h k runs the function describe-key, which looks up the function mapped to the key strokes provided, and presents a description of the function which will be run when these keys are pressed. C-h c runs the function describe-key-briefly, which only displays the function name mapped to given key seq...

C-h f runs the function describe-function, which displays information on the usage and purpose of a given function. This is especially useful for functions that do not have a mapped key binding that can be used for documentation lookup via C-h k.

Another powerful & mature concurrency tool in Haskell is Software Transactional Memory, which allows for multiple threads to write to a single variable of type TVar a in an atomic manner. TVar a is the main type associated with the STM monad and stands for transactional variable. They're used m...

The Data.Vector module provided by the vector is a high performance library for working with arrays. Once you've imported Data.Vector, it's easy to start using a Vector: Prelude> import Data.Vector Prelude Data.Vector> let a = fromList [2,3,4] Prelude Data.Vector> a fromList [2,3,4]...

Intersection of Hashes To get the intersection of two hashes, return the shared keys the values of which are equal: hash1 = { :a => 1, :b => 2 } hash2 = { :b => 2, :c => 3 } hash1.select { |k, v| (hash2.include?(k) && hash2[k] == v) } # => { :b => 2 } Union (...

Many unbound generic parameters, like those used in a static method, cannot be recovered at runtime (see Other Threads on Erasure). However there is a common strategy employed for accessing the type satisfying a generic parameter on a class at runtime. This allows for generic code that depends on ac...

Synopsis A fully functional demo of Firebase v3 Web authentication viewable here. Sign in with Facebook, Github, Google, Twitter, password based, and anonymous accounts. The code, available on Github, is easy to read and follow and is well documented. The focus is on the fully functional authent...

When your app crashes, Xcode will enter the debugger and show you more information about the crash: The most important parts are: The red arrow The red arrow displays which line of code crashed & why it crashed. The debugger console Many crashes log more information to the debugger consol...

import pandas as pd import numpy as np import matplotlib.pyplot as plt # I want 7 days of 24 hours with 60 minutes each periods = 7 * 24 * 60 tidx = pd.date_range('2016-07-01', periods=periods, freq='T') # ^ ^ # | ...

Consider the following example: @sky-blue: #87ceeb; @dark-sky-blue: @sky-blue + #333; body { background-color: @dark-sky-blue; } The above example gives you: body { background-color: #baffff; } Here it explains how to declare a variable and also make operations on a particular va...

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...

Apart from types as a template parameter we are allowed to declare values of constant expressions meeting one of the following criteria: integral or enumeration type, pointer to object or pointer to function, lvalue reference to object or lvalue reference to function, pointer to member, st...

def to_flare_json(df, filename): """Convert dataframe into nested JSON as in flare files used for D3.js""" flare = dict() d = {"name":"flare", "children": []} for index, row in df.iterrows(): parent = row[...

There are two ways to create object mocked by Mockito: via annotation via mock function Via annotation: With a JUnit test runner: @RunWith(MockitoJUnitRunner.class) public class FooTest { @Mock private Bar barMock; // ... } You can also use Mockito's JUnit @Rule, which...

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...

Firstly you have to add Xamarin.Android.Support.V7.AppCompat library for NuGet: https://www.nuget.org/packages/Xamarin.Android.Support.v7.AppCompat/ In the "values" folder under "Resources" add new xml file called "styles.xml": "styles.xml" file should co...