Android Detection with JavaScript or PHP

Hello Friends

You have a web application and you want to detect that if your Application is opened from android device than it will be redirect to any other URL that will be Android compatible.This is a good solution for you.

What’s obvious is that Android development is a hot topic that will only grow. Here are a few methods by which you can detect iOS‘ main competitor: Android.

The JavaScript

Searching the user agent string for “Android” is the quickest method:

var ua = navigator.userAgent.toLowerCase();
var isAndroid = ua.indexOf("android") > -1; //&& ua.indexOf("mobile");
if(isAndroid)
{
// Do something! // Redirect to Android-site? window.location = 'http://android.viralsolani.co';
}

The PHP

Again, we’ll use PHP’s strstr function to search for Android in the user agent:

$ua = strtolower($_SERVER['HTTP_USER_AGENT']);
if(stripos($ua,'android') !== false){// && stripos($ua,'mobile') !== false) {
header('Location: http://android.viralsolani.co');
exit();
}

Bonus! .htaccess Detection

We can even use .htaccess directives to detect and react to Android devices!

RewriteCond %{HTTP_USER_AGENT} ^.*Android.*$
 RewriteRule ^(.*)$ http://android.viralsolani.co [R=301]

And there you have it: three different Android device detection! Have fun with your mobile development!

Resource :

http://davidwalsh.name/detect-android

Thanks

 

Understanding Abstract Classes in PHP

Abstract classes are an often misunderstood feature of PHP object-oriented programming (OOP) and the source of confusion when considered versus an Interface. The obvious reason for using an Interface is that a child class can implement multiple interfaces but extend only a single abstract class. However, if multiple inheritance is not required then people often go with abstract classes just because they provide the option of later adding base functionality within the abstract class. This is not entirely unreasonable but the reasons for creating abstract classes should be more than that.
Why Use Abstract Classes?

An Abstract class provides concrete base functions as well as abstract functions that must be implemented by concrete child classes—binding them into a contract so to speak, if they wish to make use of the base functionality.

This is a subtle but important point and this is where abstract classes really shine. They can call abstract functions from within base concrete functions. Jumping straight to an example is the clearest way to explain this.

abstract class Animal {
  function greeting() {
    $sound = $this->sound();      // exists in child class by contract
    return strtoupper($sound);
  }
  abstract function sound();      // this is the contract
}

class Dog extends Animal {
  function sound() {              // concrete implementation is mandatory
    return "Woof!";
  }
}

$dog = new Dog();
echo $dog->greeting();            // WOOF!

This opens up a whole lot of interesting possibilities. For example, you can write a drive() function that calls $this->start(); $this->accelerate(); in an abstract class. Then create a motorcycle class that defines its own start() and accelerate() functions that may be different from those in the car class. In turn, the motorcycle and car can both be driven by just calling drive() without having to implement it locally.
Characteristics of Abstract Classes

Make a note of these characteristics to lock down your understanding of abstract classes:

  • Single inheritance. Child classes can extend only one class at a time.
  • Abstract classes cannot be instantiated — no new Animal();
  • Abstract classes can define class variables of type const only.
  • Abstract class A can be extended by another abstract class B. Abstract class B can implement none or any of the abstract functions in A.
  • In the previous case, a child class C which extends abstract class B must implement all abstract functions in B as well as the abstract functions in A which have not already been implemented in B.
  • The signature of the concrete functions and abstract functions must be the same. However, if an abstract function is defined as abstract function speak($greeting); then it is okay to implement it as function speak($greeting, $shout = FALSE) but not function speak($greeting, $shout).
  • The visibility of functions in the child classes must be the same or less restrictive than the parent class. Thus, a protected abstract function can be implemented as either protected or public but not private.
  • Declaring functions as static abstract throws a strict warning in PHP 5.2 or earlier, however, as of PHP 5.3 this is allowed.

PHP SDK & Graph API base Facebook Connect Tutorial

Hello Friends

In My current application I’ve used facebook Graph API to fetched data from facebook with the help of  PHP SDK. I’ve explored so many tutorials on web but I found some links are very helpful and easy to understand Here I’m sharing those links. By surfing through these links you can get to know these below things

1 . How you can create your application in Facebook and How you can use APP ID and APP Secret? 

2. How you can connect to Facebook from your Application?

3. How you can fetch data with the help of Facebook Graph API and PHP-SDK?

4. How you can Design your Facebook Application?

So here are some useful links.

  1. http://www.londatiga.net/it/how-to-create-facebook-application-with-php-for-beginner/
  2. http://thinkdiff.net/facebook/php-sdk-3-0-graph-api-base-facebook-connect-tutorial/
  3. http://net.tutsplus.com/tutorials/php/wrangling-with-the-facebook-graph-api/
  4. http://www.joeyrivera.com/2010/facebook-graph-api-app-easy-w-php-sdk/
  5. http://net.tutsplus.com/tutorials/javascript-ajax/design-and-code-an-integrated-facebook-app/

To Create a New Application in Facebook.

https://developers.facebook.com/apps

Graph API

https://developers.facebook.com/docs/reference/api/

PHP SDK refrence

https://developers.facebook.com/docs/reference/php/

FB Tool for Graph API Explorer

http://developers.facebook.com/tools/explorer

Hope it helps.


profile for Viral Solani at Stack Overflow, Q&A for professional and enthusiast programmers

How to Install Apache, PHP, MySQL and PHPMyAdmin in Ubuntu 11.04

If you are a PHP based web developer, you need all the software running and configured properly. Here I am talking about installing them One by One in your Ubuntu Desktop. We are installing all the applications from terminal.

How to Open Terminal:
So, to fire up the terminal follow any of these steps:

  1. If you are running Unity Desktop, click on the Ubuntu Logo at top left corner and type Terminal in the search application bar. Then click on the terminal icon.
  2. If you are running GNome Desktop, click on Applications->Accessories->Terminal
  3. For shortcut, you can also press Ctrl+Alt+T at once, to open the terminal.

How to install Apache:

1. Make sure you have the internet connection. To install apache execute the following command in the terminal:

1
sudo apt-get install apache2

It takes some time to download and install apache. After the setup completes, type http://localhost/ in your browser window to make sure apache is installed and running properly. If you see the page with It Works!, the setup of apache2 completes successfully.

How to Install PHP:

1. To install PHP 5, type following commands in the terminal one by one:

1
2
sudo apt-get install php5
sudo apt-get install libapache2-mod-php5

The first line installs PHP5 in the computer. The second one provides the PHP5 module for the Apache 2 webserver. If second one is not installed, then Apache cannot parse PHP codes in a web page.

2. After installing PHP5 and PHP module for apache, restart the apache with following code:

1
sudo /etc/init.d/apache2 restart

3. While restarting the apache server, if you see a warning as “Could not reliably determine the server’s fully qualified domain name, using 127.0.1.1 for ServerName”, then you can fix this by creating a file with the Server name. To do this type the following command in the terminal:

1
sudo gedit /etc/apache2/conf.d/fqdn

When the text editor opens, type “ServerName localhost” inside the file and click Save. Then close it. Now restart again with the above code and you will see that the warning message has gone.

4. Now, we have successfully installed php and apache web server. However, still we don’t know if PHP is successfully installed. To check this, create a file inside /var/www/ folder named test.php as:

1
sudo gedit /var/www/test.php

and write following code in it

1
<?php   phpinfo();  ?>

Save the file and type this in browser: http://localhost/test.php

If you see the various information about PHP and installed modules there, then we can confirm that Apache is parsing PHP codes. Hence the installation is successful up to this point.

How to Install MySQL:

1. To install MySQL Server in ubuntu, type following code in terminal window:

1
sudo apt-get install mysql-server libapache2-mod-auth-mysql php5-mysql

This will install latest mysql server and other necessary PHP modules for recognizing mysql functions from PHP code. While installing MySQL server, you may require to enter the password for MySQL root user.

How to Install PHPMyAdmin:

1. To Install PHPMyAdmin, type the following codes in the terminal:

1
sudo apt-get install phpmyadmin

While installing PHPMyAdmin, you may require to select the web server. In such case, tick the Apache2 Server and proceed with the installation. You may also require to input MySQL root user password during installation.

Once the installation completes, type this in your browser window to confirm the successful installation of PHPMyAdmin: http://localhost/phpmyadmin/index.php.

Now, you are finished. Your environment is setup and you can enjoy using all these applications. Next, you can install other applications that may be necessary such as Eclipse, GIMP etc.

The Right Way to Get a File Extension in PHP

I made a recent search on retrieving file extensions in PHP.

I found out that a lot have been re-inventing the wheel. They have been creating code for functionality that PHP already has. This is one example of re-inventing the wheel

function get_file_extension($file_name)
{
return substr(strrchr($file_name,’.’),1);
}

Another example was this:

function file_extension($filename)
{
return end(explode(“.”, $filename));
}

PHP already has a function that does the same thing and more.

Welcome, pathinfo.

$file_path = pathinfo(‘/www/htdocs/your_image.jpg’);
echo “$file_path [‘dirname’]\n”;
echo “$file_path [‘basename’]\n”;
echo “$file_path [‘extension’]\n”;
echo “$file_path [‘filename’]\n”; // only in PHP 5.2+


// Output
/www/htdocs
your_image.jpg
jpg
your_image

A much easier way to use the constants:
[PATHINFO_DIRNAME | PATHINFO_BASENAME | PATHINFO_EXTENSION | PATHINFO_FILENAME]

PATHINFO_DIRNAME – the directory
PATHINFO_BASENAME – the file name
PATHINFO_EXTENSION – the extension
PATHINFO_FILENAME – the filename without the extension

echo pathinfo(‘/www/htdocs/your_image.jpg’, PATHINFO_EXTENSION);

// Output

jpg

Difference between require, require_once, include and include_once

All these functions require, require_once, include and include_once are used to include the files in the php page but there is slight difference between these functions.

Difference between require, require_once, include, include_once
Difference between require and include is that if the file you want to include is not found then include function give you warning and executes the remaining code in of php page where you write the include function. While require gives you fatal error if the file you want to include is not found and the remaining code of the php page will not execute.

If you have many functions in the php page then you may use require_once or include_once. There functions only includes the file only once in the php page. If you use include or require then may be you accidentally add two times include file so it is good to use require_once or include_once which will include your file only once in php page. Difference between require_once and include_onceis same as the difference between require and include.