ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Filtering display objects
// Example of removing a glow filter from a set of filters, where the
//filter you want to remove is the only GlowFilter instance applied
// to the filtered object.
var tempFilters:Array = filteredObject.filters;
// Loop through the filters to find the index of the GlowFilter instance.
var glowIndex:int;
var numFilters:int = tempFilters.length;
for (var i:int = 0; i < numFilters; i++)
{
if (tempFilters[i] is GlowFilter)
{
glowIndex = i;
break;
}
}
// Remove the glow filter from the array.
tempFilters.splice(glowIndex, 1);
// Apply the new set of filters to the display object.
filteredObject.filters = tempFilters;
In a more complex case, such as if the filter to remove is selected at runtime, the best approach is to keep a separate,
persistent copy of the filter array that serves as the master list of filters. Any time you make a change to the set of filters,
change the master list then apply that filter array as the filters property of the display object.
For example, in the following code listing, multiple convolution filters are applied to a display object to create different
visual effects, and at a later point in the application one of those filters is removed while the others are retained. In this
case, the code keeps a master copy of the filters array, as well as a reference to the filter to remove. Finding and
removing the specific filter is similar to the preceding approach, except that instead of making a temporary copy of the
filters array, the master copy is manipulated and then applied to the display object.
Last updated 6/6/2012
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