Tutorial by Examples: t

Retrieving sensor information from the onboard sensors: public class MainActivity extends Activity implements SensorEventListener { private SensorManager mSensorManager; private Sensor accelerometer; private Sensor gyroscope; float[] accelerometerData = new float[3]; f...

The sensor values returned by Android are with respective to the phone's coordinate system (e.g. +Y points towards the top of the phone). We can transform these sensor values into a world coordinate system (e.g. +Y points towards magnetic North, tangential to the ground) using the sensor managers ro...

Make sure the following dependency is added to your app's build.gradle file under dependencies: compile 'com.android.support:design:25.3.1' Show the hint from an EditText as a floating label when a value is entered. <android.support.design.widget.TextInputLayout android:layout_width=&qu...

TabLayout provides a horizontal layout to display tabs, and is commonly used in conjunction with a ViewPager. Make sure the following dependency is added to your app's build.gradle file under dependencies: compile 'com.android.support:design:25.3.1' Now you can add items to a TabLayout in your ...

One of the most used attribute for LinearLayout is the weight of its child views. Weight defines how much space a view will consume compared to other views within a LinearLayout. Weight is used when you want to give specific screen space to one component compared to other. Key Properties: wei...

Hex Opacity Values ------------------------------ | Alpha(%) | Hex Value | ------------------------------ | 100% | FF | | 95% | F2 | | 90% | E6 | | 85% | D9 | | 80% | ...

<svg> <defs> <linearGradient id='g' y1="100%" x2="100%"> <stop offset='0%' stop-color='yellow' /> <stop offset='100%' stop-color='green' /> </linearGradient> </defs> <rect width=...

<svg> <defs> <radialGradient id="g"> <stop offset="10%" stop-color="green" /> <stop offset="90%" stop-color="white" /> </radialGradient> </defs> <rect width='100%' height...

JSON is a cross language, widely used method to serialize data Supported data types : int, float, boolean, string, list and dict. See -> JSON Wiki for more Here is an example demonstrating the basic usage of JSON :- import json families = (['John'], ['Mark', 'David', {'name': 'Avraham'}]) ...

Here is an example demonstrating the basic usage of pickle:- # Importing pickle try: import cPickle as pickle # Python 2 except ImportError: import pickle # Python 3 # Creating Pythonic object: class Family(object): def __init__(self, names): self.sons = names ...

Identifying your user is only part of security. Once you know who they are, you need a way to control their access to data in your database. Firebase Database Rules allow you to control access for each user. For example, here's a set of security rules that allows anyone to read the path /foo/, but n...

The Firebase Realtime Database is schemaless. This makes it easy to change things as you develop, but once your app is ready to distribute, it's important for data to stay consistent. The rules language includes a .validate rule which allows you to apply validation logic using the same expressions u...

The Firebase Realtime Database allows ordering and querying data. For small data sizes, the database supports ad hoc querying, so indexes are generally not required during development. Before launching your app though, it is important to specify indexes for any queries you have to ensure they contin...

You can save your code snippets for use later simply by drag and drop. For eg: if you have an NSLog statement that used for so many places somewhere else in the project, then you can save the NSLog statements to code snippets library. Drag the NSLog statement to code snippet library. Now you c...

The most simple way to create a thread is by calling a selector "in the background". This means a new thread is created to execute the selector. The receiving object can be any object, not just self, but it needs to respond to the given selector. - (void)createThread { [self performS...

Using a subclass of NSThread allows implementation of more complex threads (for example, to allow passing more arguments or to encapsulate all related helper methods in one class). Additionally, the NSThread instance can be saved in a property or variable and can be queried about its current state ...

Every thread has access to a mutable dictionary that is local to the current thread. This allows to cache informations in an easy way without the need for locking, as each thread has its own dedicated mutable dictionary: NSMutableDictionary *localStorage = [NSThread currentThread].threadDictionary;...

$ mkdir 20{09..11}-{01..12} Entering the ls command will show that the following directories were created: 2009-01 2009-04 2009-07 2009-10 2010-01 2010-04 2010-07 2010-10 2011-01 2011-04 2011-07 2011-10 2009-02 2009-05 2009-08 2009-11 2010-02 2010-05 2010-08 2010-11 2011-02 2011-05 2011-08 2011...

$ cp .vimrc{,.bak} This expands into the command cp .vimrc .vimrc.bak.

$ mv filename.{jar,zip} This expands into mv filename.jar filename.zip .