Array.splice() and Array.slice() are 2 powerful functions that you can use to manipulate the content of your List component. If used effectively, you can achieve a List filtering effect without using any other complex filtering techniques.
First off, what happens when you do this:
var myArray1:Array = new Array();
var myArray2:Array = new Array();
//Push an object to Array1
myArray1.push(new String("ALL"));
//Assign Array1 content to Array2
myArray2 = myArray1;
//Push another object to Array1
myArray1.push(new String("Only for Array1"));
Whatever objects you add to myArray1, automatically gets into myArray2 because of the Array assignment. In your application if you want the 2 arrays two share the content initially but not bound together at a later stage, you need to ‘slice’ the Array:
//Do not do this myArray2 = myArray1; //Do this to create a copy of myArray1 myArray2 = myArray1.slice(0);
Splicing, is another technique that will allow you to modify the content of the array without creating a copy of it.
//Remove the first element of myArray1 and assign the content to myArray2. //When you modify myArray1, myArray2 will also change. myArray2 = myArray1.splice(0,1);
You can follow these Array manipulation techniques in your application to create List components with filters, which will bind different arrays to the list at run time.
Here’s an application I built for the Android market, a simple action items tracking system using associative arrays and filters:
See also: