Theo\’s Blog

I was having some difficulties with copies of ActionScript Arrays.

I used to think that code like this

var a:Array = new Array(1,2,3);
var b:Array = a;

would assign a copy of a to b. Today I investigated that assumption. At first my assumption got strengthened by the discovery that there is no copy constructor for arrays and also no copy function in the Array prototype. But as I learned from working with Flash and ActionScript, first looks can be deceiving. Luckily looking some further I found a good explaination of ActionScript Array copying on kirupa. You can use the slice function to really copy arrays. Like this:

var a:Array = new Array (1,2,3);
var b:Array=a.slice();

And copying of a 2 dimensional would then go like this

var a:Array = new Array ( new Array(1,2,3), new Array(4,5,6) );
var b:Array = new Array();
for(var i:Number=0; i < a.length; i++) b[i] = a[i].slice();

Good to finally know how ActionScript Arrays work. Saves me a lot of trouble.

To dynamically create a button (clickable MovieClip) with ActionScript you only have to define the onRelease event. For example this makes a button out of your MovieClip ‘MyMovieClip’.

class com.mywebsite.MyMovieClip extends MovieClip
{

function MyMovieClip()
{}
public function onRelease()
{
//Do Something
}

}

Frustrating thing however is that your MovieClip is now only clickable on its graphics. So say it has some text and some lines, it will be only clickable when the mouse is exactly hovering above character-pixels or precisely above the line-pixels.

I found a real easy trick that makes a user defined region clickable. Dynamically draw a invisible shape(!) defining the region you want to be clickable using the Flash drawing API. This invisible drawing is impossible in the authoring tool. I tried it, but invisible graphics collapse/disappear.

I defined a function handling the onLoadInit event to draw my “click”-region.

public function onLoadInit()
{

drawClickableRegion();

}

private function drawClickableRegion()
{

beginFill(0xFFFFFF, 0);
moveTo(-2.5, -5);
lineStyle(0, 0xFFFFFF, 0);
lineTo(-2.5,5);
lineTo(35,5);
lineTo(35,-5);
lineTo(-2.5,-5);
endFill();

}

As you can see, my code draws a box between -2.5,-5 and 35,5. I use fill- and line-color 0xFFFFFF with an alpha 0. You can use any arbitrarily chosen color but make sure you set the alpha to 0 to make your shape invisible. From now onwards your dynamically created MovieClip is a button. Remember to redraw this region whenever you use the clear() function on this MovieClip elsewhere in your code.

Someone found my blog searching for “flash actionscript string[] array”.

I think this person is looking for a way to build a string array in ActionScript. That’s easy.

The ActionScript language reference explains the Array constructor like this:

public Array([value:Object])

Let’s you create an array. You can use the constructor to create different types of arrays: an
empty array, an array with a specific length but whose elements have undefined values, or an
array whose elements have specific values.

• Usage 1: If you don’t specify any parameters, an array with a length of 0 is created.
• Usage 2: If you specify only a length, an array is created with length number of elements. The value of each element is set to undefined.
• Usage 3: If you use the element parameters to specify values, an array is created with specific values.

Parameters

value:Object [optional] – Either:

• An integer that specifies the number of elements in the array.
• A list of two or more arbitrary values. The values can be of type Boolean, Number, String,Object, or Array. The first element in an array always has an index or position of 0.

So here are two examples of how you could go about creating a String array in Flash

var str_example_array:Array = new Array(“Belinda”, “Gina”, “Kathy”, “Charlotte”,”Jane”);

Or

var str_example_array:Array = new Array();
str_example_array[0] = “Belinda”;
str_example_array[1] = “Gina”;
str_example_array[2] = “Kathy”;
str_example_array[3] = “Charlotte”;
str_example_array[4] = “Jane”;

I hope that this is of help. If you have questions, ask them!

Actionscript 2.0 has serious shortcomings with regard to String functions. Luckily I’ve not been the only-one frustrated by this, and lot’s of people have already done lot’s of work to overcome Macromedia’s shortcomings. Earlier I found this “String Functions Macromedia forgot“, and posted about how I made it in to a Toolkit instead of extending the String prototype. Today I wrote a function that is a small alteration of the String fullreplace function that might be very useful for you too.

What the fullreplace function does is too replace in a given String s occurrences of a sub-string matchwhat with a String replacewith. I was trying to use this function in the context of a text search functionality. In my Flash application I gave people the opportunity to search for a certain string. And have that string highlighted in the text results. Function fullreplace did not completely have the intended results.

For example;

When searching for “daan”, a search result “… Daan Roosegaarde …” would be displayed as; “… daan Roosegaarde …”. Of course I would have preferred this to be; “… Daan Roosegaarde …”

I called my function fullEmphasize. The function searches ignoring case, but replaces the matchwhat string with an emphasized version of the matchwhat that preserves the upper- and lowercases of the searchresult.

// used by fullEmphasize function, this function returns
// an array of the lowercase string split by the lowercase
// word we’re replacing
public static function rawfind(s:String ,match:String):Array
{

var sources = s.toLowerCase();
match = match.toLowerCase();
return sources.split(match);

}

// Emphasize all occurences of `matchwhat` with “<b>”+matchwhat+”</b>”
public static function fullEmphasize(s:String, matchwhat:String):String
{

var returnstring = “”;
var matches = rawfind(s,matchwhat); var atindex = 0;
var endat = matches.length – 1;

for(var i=0; i<matches.length; i++)
{

var matchedword = matches[i]; returnstring += s.substr(atindex, matchedword.length);

if(i < endat)
{

atindex += matchedword.length;
returnstring += “<b>”+s.substr(atindex,matchwhat.length)+”</b>”;

}

atindex += matchwhat.length;

}

return returnstring;

}

UPDATE March 7 2007:

Jack provided a better implementation for the rawfind function

[QOUTE from Jack's comment]
I like your code, but there is one small problem with the rawfind function. It will return an array of characters if the empty string is passed in as the match parameter (ECMA-262). Below is my fix for this problem as well as a variation of your fullEmphasize function which emphasizes matched strings by color( assuming an html enabled text ).

// used by fullEmphasize function, this function returns
// an array of the lowercase string split by the lowercase
// word we’re replacing
public static function rawfind(s:String ,match:String):Array
{
if( match != “” )
{
var sources = s.toLowerCase();
match = match.toLowerCase();
return sources.split(match);
}
else // return unaltered string as array element 0
{
var rArray = new Array();
rArray.push(s);
return rArray;
}
}
[/QOUTE]

Today once again I was confronted with strange Flash behaviour. This time the struggle was about using CSS style on html text in a Flash TextField using an embedded font. I hope I help someone with writing down what I found out.

Okay the problem was this. When using an embedded font in combination with a TextField.StyleSheet, part of my html text disappeared. I solved this by specifying for each HTML tag the font to be used. This is part of what my CSS initialization looked like:

var globalCSS:TextField.StyleSheet = new TextField.StyleSheet();
globalCSS.parseCSS(“a:link {color: #1b5085; font-family: Frutiger55_Bold_Font; font-weight: bold; text-decoration: none; } a:hover {color: #1b5085; font-family: Frutiger55_Bold_Font; font-weight: bold; text-decoration: underline; } b { font-family: Frutiger55_Bold_Font; font-weight: bold; } i { font-family: Frutiger55_Font; } ul { font-family: Frutiger55_Font; } li { font-family: Frutiger55_Font; } .blogHeader { font-family: Frutiger55_Bold_Font; font-size: 14; } .blogDate { font-family: Frutiger55_Bold_Font; font-size: 10; }”);

The font names that I used for the “font-family” CSS property correspond to the library linkage identifier for “export for ActionScript”. (You can set this by right clicking on your embedded font in the library and checking the checkbox “export for ActionScript”.) As you see I included a separate ‘regular’ (Frutiger55_Font) and ‘bold’ (Frutiger55_Bold_Font) font. Just to display parts of the text bold and others not. This was necessary in my situation, but I’ve seen fonts that did not require this. Hope this is of some help to someone. It would have saved me a lot of frustration if I had found something similar!