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AlertDialog is a subclass of Dialog that can display one, two or three buttons. If you only want to display a String in this dialog box, use the setMessage() method. The AlertDialog from android.app package displays differently on different Android OS Versions. The Android V7 Appcompat library pro...

Maybe Maybe is a Functor containing a possibly-absent value: instance Functor Maybe where fmap f Nothing = Nothing fmap f (Just x) = Just (f x) Maybe's instance of Functor applies a function to a value wrapped in a Just. If the computation has previously failed (so the Maybe value is ...

List.sortWith allows you to sort lists with data of any shape - you supply it with a comparison function. compareBools : Bool -> Bool -> Order compareBools a b = case (a,b) of (False, True) -> LT (True, False) -> GT _ -> ...

Only the homepage works, all other pages return 404 Make sure mod_rewrite module has been installed in Apache and been enabled to load. See step 2 for info on how to do this here: https://www.digitalocean.com/community/tutorials/how-to-set-up-mod_rewrite-for-apache-on-ubuntu-14-04 Make sure the y...

Profiling concatanation of numbers python -m timeit "'-'.join(str(n) for n in range(100))" 10000 loops, best of 3: 29.2 usec per loop python -m timeit "'-'.join(map(str,range(100)))" 100000 loops, best of 3: 19.4 usec per loop

The source code with @profile directive before the function we want to profile: import requests @profile def slow_func(): s = requests.session() html=s.get("https://en.wikipedia.org/").text sum([pow(ord(x),3.1) for x in list(html)]) for i in range(50): s...

C++14 Those following complex user literals are declared in the namespace std::literals::complex_literals, where both literals and complex_literals are inline namespaces. Access to these operators can be gained with using namespace std::literals, using namespace std::complex_literals, and using nam...

This will only install PHP. If you wish to serve a PHP file to the web you will also need to install a web-server such as Apache, Nginx, or use PHP's built in web-server (php version 5.4+). If you are in a Ubuntu version below 16.04 and want to use PHP 7 anyway, you can add Ondrej's PPA repo...

You can combine the results of two identically structured queries with the UNION keyword. For example, if you wanted a list of all contact info from two separate tables, authors and editors, for instance, you could use the UNION keyword like so: select name, email, phone_number from authors u...

db.people.createIndex({name: 1, age: -1}) This creates an index on multiple fields, in this case on the name and age fields. It will be ascending in name and descending in age. In this type of index, the sort order is relevant, because it will determine whether the index can support a sort opera...

The NVIDIA installation guide ends with running the sample programs to verify your installation of the CUDA Toolkit, but doesn't explicitly state how. First check all the prerequisites. Check the default CUDA directory for the sample programs. If it is not present, it can be downloaded from the offi...

:g/Hello/d Will delete every line containing the text "Hello". Important note: This is not the normal mode command d, this is the ex command :d. You can use the global command to apply normal mode keystrokes instead of ex commands by prepending normal or norm to the command. For exampl...

Define your payload to send for possible more complex data $Payload = @{ text="test string"; username="testuser" } Use ConvertTo-Json cmdlet and Invoke-RestMethod to execute the call Invoke-RestMethod -Uri "https://hooks.slack.com/services/yourwebhookstring" -Metho...

1. Print the Hadoop version hadoop version 2. List the contents of the root directory in HDFS hadoop fs -ls / 3. Report the amount of space used and available on currently mounted filesystem hadoop fs -df hdfs:/ 4. Count the number of directories,files and bytes under the paths tha...

There are times when an include file has to generate different output from the preprocessor depending on whether the compiler is a C compiler or a C++ compiler due to language differences. For example a function or other external is defined in a C source file but is used in a C++ source file. Since...

com.google.gson library needs to be added to use this code. Here is the example string: String companyDetails = {"companyName":"abcd","address":"abcdefg"} JSON strings can be parsed using below syntax in Java: JsonParser parser = new JsonParser(); Json...

Enabling gzip compression can reduce the size of the transferred response by up to 90%, which can significantly reduce the amount of time to download the resource, reduce data usage for the client, and improve the time to first render of your pages. — PageSpeed Insights Compression can be ena...

installing npm install web-component-tester --save-dev setting up wct.conf.js module.exports = { verbose: true, plugins: { local: { browsers: ['chrome'] } } }; running node node_modules/web-component-tester/bin/wct test/index.html <html...

Computed observables are functions that can "watch" or "react" to other observables on the view model. The following example shows how you would display the total number of users and the average age. Note: The example below can also make use of pureComputed() (introduced in v3....

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";...