Tutorial by Examples: nd

Installation Volley JCenter Gradle Import //in your project's app level build.gradle compile 'com.android.volley:volley:1.0.0' Create a subclass of Application public class AppController extends Application { public static final String TAG = AppController.class .getSimpleN...

The number of seconds a script has been running. This can get quite large if shown in the shell: ~> $ echo $SECONDS 98834

Consider this example function to check if a host is up: is_alive() { ping -c1 "$1" &> /dev/null } This function sends a single ping to the host specified by the first function parameter. The output and error output of ping are both redirected to /dev/null, so the functi...

ssh -p 21 [email protected] <<EOF echo 'printing pwd' echo "\$(pwd)" ls -a find '*.txt' EOF $ is escaped because we do not want it to be expanded by the current shell i.e $(pwd) is to be executed on the remote shell. Another way: ssh -p 21 [email protected] <...

sudo -s <<EOF a='var' echo 'Running serveral commands with sudo' mktemp -d echo "\$a" EOF $a needs to be escaped to prevent it to be expanded by the current shell Or sudo -s <<'EOF' a='var' echo 'Running serveral commands with sudo' mktemp -d e...

Inside your layout, add a Login button with the following code: <com.twitter.sdk.android.core.identity.TwitterLoginButton android:id="@+id/twitter_login_button" android:layout_width="wrap_content" android:layout_height="wrap_content" and...

foo = "bar" foo[0] = "c" # Error Immutable variable value can not be changed once they are created.

foo = ("bar", 1, "Hello!",) foo[1] = 2 # ERROR!! Second line would return an error since tuple members once created aren't assignable. Because of tuple's immutability.

Each time this parameter is referenced, a random integer between 0 and 32767 is generated. Assigning a value to this variable seeds the random number generator (source). ~> $ echo $RANDOM 27119 ~> $ echo $RANDOM 1349

Windows in SFML are represented by one of two classes: sf::Window is a generic window provided by the operating system including an OpenGL render context. sf::RenderWindow is a specialized version of sf::Window that also acts as a sf::RenderTarget, allowing SFML's primitives to be rendered to it...

On systems that use the System-V style init scripts, such as RHEL/CentOS 6: service <service> start service <service> stop On systems using systemd, such as Ubuntu (Server and Desktop) >= 15.04, and RHEL/CentOS >= 7: systemctl <service> dnsmasq systemctl <service> ...

You can combine named arguments with optional parameters. Let see this method: public sealed class SmsUtil { public static bool SendMessage(string from, string to, string message, int retryCount = 5, object attachment = null) { // Some code } } When you want to call t...

Date and time without time zone information LocalDateTime dateTime = LocalDateTime.of(2016, Month.JULY, 27, 8, 0); LocalDateTime now = LocalDateTime.now(); LocalDateTime parsed = LocalDateTime.parse("2016-07-27T07:00:00"); Date and time with time zone information ZoneId zoneId = Zon...

LocalDate tomorrow = LocalDate.now().plusDays(1); LocalDateTime anHourFromNow = LocalDateTime.now().plusHours(1); Long daysBetween = java.time.temporal.ChronoUnit.DAYS.between(LocalDate.now(), LocalDate.now().plusDays(3)); // 3 Duration duration = Duration.between(Instant.now(), ZonedDateTime.par...

layer.masksToBounds = true; layer.cornerRadius = 8;

The revert command allows discarding unwanted uncommitted changes. Reverting changes to a single file. hg revert example.c Reverting all changes. This will discard all changes not just the current directory. hg revert --all hg will output which files were reverted. reverting exa...

In C++ methods that differs only by const qualifier can be overloaded. Sometimes there may be a need of two versions of getter that return a reference to some member. Let Foo be a class, that has two methods that perform identical operations and returns a reference to an object of type Bar: class ...

A lot of users find themselves in a situation where they just want to copy, move or delete a line quickly and return to where they were. Usually, if you'd want to move a line which contains the word lot below the current line you'd type something like: /lot<Esc>dd<C-o>p But to boost...

Background: if you work on a project like the Linux kernel, rather than make a pull request you will need to submit your commits to a listserv for review. This entry details how to use git-send email with Gmail. Add the following to your .gitconfig file: [sendemail] smtpserver = smtp.googlema...

To list files and folders inside current directory, we use ls command: user@host:/$ ls bin boot cdrom dev etc home initrd.img lib lib64 lost+found media mnt opt proc root run sbin srv sys tmp usr var vmlinuz ls prints folder structure in simple view, color coded by type....