You
can add event listeners to a TextLine instance just as you can to
other display objects. For example, you can detect when a user rolls
the mouse over a text line or a user clicks the line. The following
example detects both of these events. When you roll the mouse over
the line, the cursor changes to a button cursor and when you click
the line, it changes color.
package
{
import flash.text.engine.*;
import flash.ui.Mouse;
import flash.display.Sprite
import flash.events.MouseEvent;
import flash.events.EventDispatcher;
public class EventHandlerExample extends Sprite
{
var textBlock:TextBlock = new TextBlock();
public function EventHandlerExample():void
{
var str:String = "I'll change color if you click me.";
var fontDescription:FontDescription = new FontDescription("Arial");
var format:ElementFormat = new ElementFormat(fontDescription, 18);
var textElement = new TextElement(str, format);
textBlock.content = textElement;
createLine(textBlock);
}
private function createLine(textBlock:TextBlock):void
{
var textLine:TextLine = textBlock.createTextLine(null, 500);
textLine.x = 30;
textLine.y = 30;
addChild(textLine);
textLine.addEventListener("mouseOut", mouseOutHandler);
textLine.addEventListener("mouseOver", mouseOverHandler);
textLine.addEventListener("click", clickHandler);
}
private function mouseOverHandler(event:MouseEvent):void
{
Mouse.cursor = "button";
}
private function mouseOutHandler(event:MouseEvent):void
{
Mouse.cursor = "arrow";
}
function clickHandler(event:MouseEvent):void {
if(textBlock.firstLine)
removeChild(textBlock.firstLine);
var newFormat:ElementFormat = textBlock.content.elementFormat.clone();
switch(newFormat.color)
{
case 0x000000:
newFormat.color = 0xFF0000;
break;
case 0xFF0000:
newFormat.color = 0x00FF00;
break;
case 0x00FF00:
newFormat.color = 0x0000FF;
break;
case 0x0000FF:
newFormat.color = 0x000000;
break;
}
textBlock.content.elementFormat = newFormat;
createLine(textBlock);
}
}
}
Mirroring events
You
can also mirror events on a text block, or on a portion of a text
block, to an event dispatcher. First, create an EventDispatcher
instance and then assign it to the
eventMirror
property
of a TextElement instance. If the text block consists of a single
text element, the text engine mirrors events for the entire text
block. If the text block consists of multiple text elements, the
text engine mirrors events only for the TextElement instances that
have the
eventMirror
property set. The text in
the following example consists of three elements: the word "Click",
the word "here", and the string "to see me in italic". The example
assigns an event dispatcher to the second text element, the word
"here", and adds an event listener, the
clickHandler()
method.
The
clickHandler()
method changes the text to italic.
It also replaces the content of the third text element to read,
"Click here to see me in normal font!".
package
{
import flash.text.engine.*;
import flash.ui.Mouse;
import flash.display.Sprite;
import flash.events.MouseEvent;
import flash.events.EventDispatcher;
public class EventMirrorExample extends Sprite
{
var fontDescription:FontDescription = new FontDescription("Helvetica", "bold");
var format:ElementFormat = new ElementFormat(fontDescription, 18);
var textElement1 = new TextElement("Click ", format);
var textElement2 = new TextElement("here ", format);
var textElement3 = new TextElement("to see me in italic! ", format);
var textBlock:TextBlock = new TextBlock();
public function EventMirrorExample()
{
var myEvent:EventDispatcher = new EventDispatcher();
myEvent.addEventListener("click", clickHandler);
myEvent.addEventListener("mouseOut", mouseOutHandler);
myEvent.addEventListener("mouseOver", mouseOverHandler);
textElement2.eventMirror=myEvent;
var groupVector:Vector.<ContentElement> = new Vector.<ContentElement>;
groupVector.push(textElement1, textElement2, textElement3);
var groupElement:GroupElement = new GroupElement(groupVector);
textBlock.content = groupElement;
createLines(textBlock);
}
private function clickHandler(event:MouseEvent):void
{
var newFont:FontDescription = new FontDescription();
newFont.fontWeight = "bold";
var newFormat:ElementFormat = new ElementFormat();
newFormat.fontSize = 18;
if(textElement3.text == "to see me in italic! ") {
newFont.fontPosture = FontPosture.ITALIC;
textElement3.replaceText(0,21, "to see me in normal font! ");
}
else {
newFont.fontPosture = FontPosture.NORMAL;
textElement3.replaceText(0, 26, "to see me in italic! ");
}
newFormat.fontDescription = newFont;
textElement1.elementFormat = newFormat;
textElement2.elementFormat = newFormat;
textElement3.elementFormat = newFormat;
createLines(textBlock);
}
private function mouseOverHandler(event:MouseEvent):void
{
Mouse.cursor = "button";
}
private function mouseOutHandler(event:MouseEvent):void
{
Mouse.cursor = "arrow";
}
private function createLines(textBlock:TextBlock):void
{
if(textBlock.firstLine)
removeChild (textBlock.firstLine);
var textLine:TextLine = textBlock.createTextLine (null, 300);
textLine.x = 15;
textLine.y = 20;
addChild (textLine);
}
}
}
The
mouseOverHandler()
and
mouseOutHandler()
functions
set the cursor to a button cursor when it's over the word "here"
and back to an arrow when it's not.
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