nariyu memo

package jp.playwell.controls
{
    import flash.display.DisplayObject;
    import flash.events.Event;
    import flash.events.MouseEvent;
 
    import mx.controls.LinkButton;
    import mx.core.UIComponent;
    import mx.styles.CSSStyleDeclaration;
    import mx.styles.StyleManager;
 
    //--------------------------------------
    //  Styles
    //--------------------------------------
    include "../styles/metadata/FocusStyles.as"
    include "../styles/metadata/PaddingStyles.as"
    include "../styles/metadata/LeadingStyle.as"
    include "../styles/metadata/TextStyles.as"
 
    /**
     * リンクの色です.
     * 
     * @default 0x003399
     */
    [Style(name="linkColor", type="uint", format="Color", inherit="yes")]
 
    //--------------------------------------
    //  Events
    //--------------------------------------
    [Event(name="change", type="flash.events.Event")]
 
    /**
     * 
     */
    public class PageNavigator extends UIComponent
    {
        /**
         * デフォルトスタイルを設定
         * @private
         */
        private static var classConstructed:Boolean = classConstruct();
 
        /**
         * @private
         */
        private static function classConstruct():Boolean
        {
            var styleDeclaration:CSSStyleDeclaration = new CSSStyleDeclaration();
            styleDeclaration.setStyle("linkColor", 0x003399);
            StyleManager.setStyleDeclaration("PageNavigator",
                styleDeclaration, true);
            return true;
        }
 
        /**
         * コンストラクタです.
         */
        public function PageNavigator()
        {
            super();
        }
 
        //---------------------------------------
        //  private properties
        //---------------------------------------
        private var valueChanged:Boolean;
 
 
        //---------------------------------------
        //  prevLabel
        //---------------------------------------
        private var _prevLabel:String = "<";
 
        [Bindable]
        /**
         * prevLabel プロパティは前のページに戻るリンクのテキストです.
         * @default <
         */
        public function get prevLabel():String
        {
            return _prevLabel;
        }
        public function set prevLabel(value:String):void
        {
            _prevLabel = value;
            valueChanged = true;
            invalidateProperties();
            invalidateSize();
            invalidateDisplayList();
        }
 
 
        //---------------------------------------
        //  nextLabel
        //---------------------------------------
        private var _nextLabel:String = ">";
 
        [Bindable]
        /**
         * nextLabel プロパティは次のページに進むリンクのテキストです.
         * @default >
         */
        public function get nextLabel():String
        {
            return _nextLabel;
        }
        public function set nextLabel(value:String):void
        {
            _nextLabel = value;
            valueChanged = true;
            invalidateProperties();
            invalidateSize();
            invalidateDisplayList();
        }
 
 
        //---------------------------------------
        //  sidePages
        //---------------------------------------
        private var _showPages:Number = 11;
 
        /**
         * showPages プロパティは最大何ページ分のリンクを表示するかを指定します.
         * @default 11 （現在のページ + 10ページ分）
         */
        public function get showPages():Number
        {
            return _showPages;
        }
        public function set showPages(value:Number):void
        {
            _showPages = value;
            valueChanged = true;
            invalidateProperties();
            invalidateSize();
            invalidateDisplayList();
        }
 
 
        //---------------------------------------
        //  maximum
        //---------------------------------------
        private var _maximum:uint = 1;
 
        [Bindable]
        /**
         * maximum プロパティは最大ページ数を指定します.
         * @default 1
         */
        public function get maximum():uint
        {
            return _maximum;
        }
        public function set maximum(value:uint):void
        {
            _maximum = value;
            valueChanged = true;
            invalidateProperties();
            invalidateSize();
            invalidateDisplayList();
        }
 
        //---------------------------------------
        //  value
        //---------------------------------------
        private var _page:uint = 1;
 
        [Bindable]
        /**
         * page プロパティは現在のページを指定します.
         * @default 1
         */
        public function get page():uint
        {
            return _page;
        }
        public function set page(value:uint):void
        {
            _page = value;
            valueChanged = true;
            invalidateProperties();
            invalidateSize();
            invalidateDisplayList();
        }
 
 
        //---------------------------------------
        //  override protected methods
        //---------------------------------------
        override protected function commitProperties():void
        {
            super.commitProperties();
 
            if (valueChanged)
            {
                valueChanged = false;
                while (numChildren > 0) removeEventListeners(removeChildAt(0));
 
                _maximum = isNaN(maximum) ? 1 : uint(maximum);
                _page = isNaN(page) ? 1 : Math.min(maximum, uint(page));
 
                var leftPages:uint = Math.floor((showPages - 1) / 2);
                var rightPages:uint = Math.ceil((showPages - 1) / 2);
                var min:uint = Math.max(1, page - leftPages);
                var max:uint = min + showPages - 1;
                if (max > maximum)
                {
                    min = Math.max(1, min - max + maximum);
                    max = maximum;
                }
 
                if (maximum > 1)
                {
                    if (page > 1) addLink(prevLabel);
 
                    var link:LinkButton;
                    for (var i:uint = min; i <= max; i++)
                    {
                        link = addLink(i.toString());
                        if (i == page)
                        {
                            link.mouseEnabled = false;
                            link.setStyle("textDecoration", "none");
                            link.setStyle("color", getStyle("color"));
                        }
                    }
 
                    if (page < maximum) addLink(nextLabel);
                }
            }
        }
        override protected function measure():void
        {
            super.measure();
 
            var w:uint = 0;
            var h:uint = 0;
 
            var n:uint = numChildren;
            var child:DisplayObject;
            for (var i:uint = 0; i < n; i++)
            {
                child = getChildAt(i);
                if (child is UIComponent)
                {
                    w += UIComponent(child).measuredWidth;
                    h = Math.max(h, UIComponent(child).measuredHeight);
                }
            }
 
            measuredWidth = measuredMinWidth = w;
            measuredHeight = measuredMinHeight = h;
        }
        override protected function updateDisplayList(w, h):void
        {
            super.updateDisplayList(w, h);
 
            var left:uint = 0;
            var n:uint = numChildren;
            var child:DisplayObject;
            for (var i:uint = 0; i < n; i++)
            {
                child = getChildAt(i);
                if (child is UIComponent)
                {
                    UIComponent(child).setActualSize(
                        UIComponent(child).measuredWidth,
                        UIComponent(child).measuredHeight);
                    UIComponent(child).move(left,
                        (unscaledHeight - UIComponent(child).measuredHeight) / 2);
                    left = UIComponent(child).x + UIComponent(child).measuredWidth;
                }
            }
        }
 
        override public function setStyle(styleProp:String, newValue:*):void
        {
            super.setStyle(styleProp, newValue);
            switch (styleProp)
            {
                case "color":
                case "linkColor":
                    var n:int = numChildren;
                    var child:DisplayObject;
                    var label:String;
                    for (var i:int = 0; i < n; i++)
                    {
                        child = getChildAt(i);
                        if (!(child is LinkButton)) continue;
                        label = LinkButton(child).label;
                        if (label.match(/^\d+$/))
                        {
                            if (parseInt(label, 10) == page)
                            {
                                LinkButton(child).setStyle("color",
                                    getStyle("color"));
                                continue;
                            }
                        }
                        LinkButton(child).setStyle("color", getStyle("linkColor"));
                    }
                    valueChanged = true;
                    invalidateProperties();
                    break;
            }
        }
 
        //---------------------------------------
        //  private methods
        //---------------------------------------
        /**
         * @private
         */
        private function addLink(label:String):LinkButton
        {
            var linkButton:LinkButton = new LinkButton();
            linkButton.styleName = this;
            linkButton.setStyle("paddingTop", 2);
            linkButton.setStyle("paddingBottom", 2);
            linkButton.setStyle("paddingLeft", 3);
            linkButton.setStyle("paddingRight", 3);
            linkButton.setStyle("textDecoration", "underline");
            linkButton.setStyle("color", getStyle("linkColor"));
            linkButton.label = label;
            linkButton.addEventListener(MouseEvent.CLICK, link_clickHandler);
            addChild(linkButton);
            return linkButton;
        }
        private function removeEventListeners(obj:DisplayObject):void
        {
            obj.removeEventListener(MouseEvent.CLICK, link_clickHandler);
        }
        private function link_clickHandler(event:MouseEvent):void
        {
            var label:String = LinkButton(event.currentTarget).label;
            switch (label)
            {
                case prevLabel:
                    page = page - 1;
                    break;
                case nextLabel:
                    page = page + 1;
                    break;
                default:
                    if (label.match(/^\d+$/))
                        page = parseInt(label, 10);
                    else
                        return;
            }
 
            dispatchEvent(new Event(Event.CHANGE));
        }
    }
}