How to shuffle an NSMutableArray in an easy way

There are several methods to sort an NSMutableArray. Here we will give you a very simple method to shuffle your NSMutableArray. This method uses the default exchangeObjectAtIndex method to shuffle the array.

Lets initialise a mutable array and add some elements to it as below:

 // Initialising the NSMutableArray

   NSMutableArray *myArray = [[NSMutableArray alloc]init];

 // Add some objects to it (say 15, here) 

   for (int i=1; i<=15; i++) {

     [myArray addObject:[NSString stringWithFormat:@"%d",i]];

   }

Now you have an array with 15 objects/elements in it. Now for sorting the above array, you just need to use the following code:

 // Code for shuffling

  for (int i = 0; i < [myArray count]; ++i) {

    [myArray exchangeObjectAtIndex:i withObjectAtIndex:((random() % ([myArray count]-i)) + i)];

  }

How to create a widget button in Corona SDK

Creating a widget button in corona, with a button press effect and a function call is as simple as below:


-- First, require 'widget' --
local widget = require("widget")

-- Create the button --
local myButton = widget.newButton{
    default = "normalImage.png",
    over = "pressedImage.png",
    width = 200, height = 200,
    onRelease = myButtonClickFunction
}

-- Position the button --
myButton.x = display.contentWidth/2
myButton.y = display.contentHeight/2

-- Then create the function you need to trigger on the button press --

function myButtonClickFunction()
    print("myButton is pressed...")
end

Array and Array Operations: PHP

Array creation:

To initialize an array in PHP:

$names_1  = array();   

                       

To add value to that array:

$names_1[] = "Bob";   

$names_1[] = "Marley";

$names_1[] = "Alex";

$names_1[] = "David";

You can also construct an array as follows:

            $arr1 = array(10,30,10,20,50);

           

To print the created array:

            print_r($names);

Array operations:

                       

To convert a string to array:

            You can use ‘explode’ to split an string with characters and add each element to array as below:

$names_2 = "Bob,Marley,Alex,David";

                       

$names_3 = explode("," , $names_2);   //--> String to array

print_r($names_3);                                                      

                       

To convert a array to string:

            If you want to get the elements from the array, and convert it into a string with each array elements separated by a character [say coma ‘,’], then you can make use of PHP ‘implode’.

print(implode(",",$names_1));               //--> Array to string

 

To eliminate similar data/elements from an array (array_unique):

$arr1 = array(10,30,10,20,50);

                       

$arr1 = array_unique($arr1);    //--> To eliminate similar data from the array

 print_r($arr1);

                       

To sort and reverse sort an array (sort and rsort):

            sort($arr1);                               //--> To sort an array

print_r($arr1);

                       

            rsort($arr1);                             //--> To reverse-sort an array

            print_r($arr1);

To add/ concatenate two arrays (array_merge):

                       

            $arr_1 = array(10,30,10,20,50);

            $arr_2 = array("Leon","CEO",41);

                       

            $arr_3 = array_merge($arr_1,$arr_2);  //--> To concatenate 2 arrays

            print_r($arr_3);

           

To get index key of an array as an array:

$arr_4 = array("name"=>" Leon ","destination"=>"CEO","age"=>41);

            print_r($arr_4);                        //--> Array with key index

            print_r(array_keys($arr_4));     //--> To get the index keys as an array

To check whether an element is in an array:

            $arr_5 = array("apple","orange","mango","grape","peach");

                       

            if(in_array("orange",$arr_5)){

     //--> To check whether an element is in an array

                        echo "Element Found...";

            }