ActionScript 3.0 Design Patterns.pdf - VideoTutorials-bg.com

Example 5-14. ListDisplayField.as
34 public function clear( ):void
35 {
36 aList = [];
37 this.update( );
38 }
39
40 internal function update( )
41 {
42 var listText:String = "";
43 // split the array to create a string separated by returns
44 for (var i:Number = 0; i < aList.length; i++) {
45 listText += aList[i] + "\r";
46 }
47 super.text = listText;
48 }
49
50 override public function set text(s:String):void
51 {
52 throw new Error("Cannot directly set text property - use
addItem( ) method");
53 }
54
55 override public function set htmlText(s:String):void
56 {
57 throw new Error("Cannot directly set htmlText property");
58 }
59
60 override public function appendText(s:String):void
61 {
62 throw new Error("Cannot append text - use addItem( ) method");
63 }
64
65 override public function replaceSelectedText(s:String):void
66 {
67 throw new Error("Cannot replace selected text");
68 }
69
70 override public function replaceText(beginIndex:int, endIndex:int,
newText:String):void
71 {
72 throw new Error("Cannot replace text");
73 }
74 }
75 }
The ListDisplayField adapter extends the TextField class, and implements the
IListDisplay interface. The constructor calls the super( ) method to invoke the constructor
in the superclass TextField (line 13). The implementation is straightforward
in that the list of items to display is stored in an array called aList that is a property
of the class. The addItem(s:String) method appends the passed string value to the
end of the aList array. The deleteItemAt(i:uint) method deletes the item at the
Example: List Display Adapter | 197