复制代码 代码如下: package Modules { import flash.display.BitmapData; import flash.display.Graphics; import mx.collections.ICollectionView; import mx.collections.IList; import mx.controls.Tree; import mx.controls.treeClasses.ITreeDataDescriptor; import mx.controls.treeClasses.TreeItemRenderer; /** * Alpha value for the Tree lines. * @default 1 */ [Style(name=\”lineAlpha\”, type=\”Number\”, format=\”Length\”, inherit=\”no\”)] /** * Color of the Tree lines. * @default 0x808080 */ [Style(name=\”lineColor\”, type=\”uint\”, format=\”Color\”, inherit=\”no\”)] /** * Thickness value for the Tree lines. * @default 1 */ [Style(name=\”lineThickness\”, type=\”Number\”, format=\”Length\”, inherit=\”no\”)] /** * The Tree line style – none, dotted (default), or solid. * @default \”dotted\” */ [Style(name=\”lineStyle\”, type=\”String\”, enumeration=\”solid\”, inherit=\”no\”)] /** * Extends TreeItemRenderer to draw the dotted lines of the tree. * It supports 3 line styles – dotted (default), solid, or none. * And the tree line color, alpha, and thickness values are configurable styles too. * * <pre> * <ui:TreeItemLinesRenderer * <b>Styles</b> * lineAlpha=\”1\” * lineColor=\”#808080\” * lineThickness=\”1\” * lineStyle=\”dotted\” * > * … * <i>child tags</i> * … * </ui:TreeItemLinesRenderer> * </pre> * * @author Chris Callendar * @date April 20th, 2009 */ public class TreeItemLinesRenderer extends TreeItemRenderer { public static const DOTTED:String = \”dotted\”; // default public static const SOLID:String = \”solid\”; public static const NONE:String = \”none\”; public function TreeItemLinesRenderer() { super(); } override public function set data(value:Object):void { super.data = value; } override protected function updateDisplayList(w:Number, h:Number):void { super.updateDisplayList(w, h); if ((w > 0) && (h > 0)) { // go up the hierarchy, drawing the vertical dotted lines for each node var tree:Tree = (owner as Tree); var desc:ITreeDataDescriptor = tree.dataDescriptor; var currentNode:Object = data; var parentNode:Object = tree.getParentItem(currentNode); // the level is zero at this node, then increases as we go up the tree var levelsUp:int = 0; var lineStyle:String = getStyle(\”solid\”); var lineColor:uint = getColorStyle(\”lineColor\”, 0x808080); var lineAlpha:Number = getNumberStyle(\”lineAlpha\”, 1); var lineThickness:Number = getNumberStyle(\”lineThickness\”, 1); var indentation:Number = tree.getStyle(\”indentation\”); // move the icon and label over to make room for the lines (less for root nodes) var shift:int = (parentNode == null ? 2 : 6) + lineThickness; if (icon) { icon.move(icon.x + shift, icon.y); } if (label) { label.move(label.x + shift, label.y); } var g:Graphics = graphics; g.clear(); if ((lineStyle != NONE) && (lineAlpha > 0) && (lineThickness > 0)) { while (parentNode != null) { var children:ICollectionView = desc.getChildren(parentNode); if (children is IList) { var itemIndex:int = (children as IList).getItemIndex(currentNode); // if this node is the last child of the parent var isLast:Boolean = (itemIndex == (children.length – 1)); drawLines(g, w, h, lineStyle, lineColor, lineAlpha, lineThickness, isLast, levelsUp, indentation); // go up to the parent, increasing the level levelsUp++; currentNode = parentNode; parentNode = tree.getParentItem(parentNode); } else { break; } } } } } protected function drawLines(g:Graphics, w:Number, h:Number, lineStyle:String, lineColor:uint, lineAlpha:Number, lineThickness:Number, isLastItem:Boolean, levelsUp:int, indentation:Number):void { var midY:Number = Math.round(h / 2); var lineX:Number = 0; if (disclosureIcon) { lineX = disclosureIcon.x + (disclosureIcon.width / 2); } else if (icon) { lineX = icon.x – 8; } else if (label) { lineX = label.x – 8; } lineX = Math.floor(lineX) – int(lineThickness / 2); // adjust the x position based on the indentation if (levelsUp > 0) { if (!isNaN(indentation) && (indentation > 0)) { lineX = lineX – (levelsUp * indentation); } else { // Invalid indentation style value return; } } var lineY:Number = h; // stop the dotted line halfway on the last item if (isLastItem) { lineY = midY; // no lines need to be drawn for parents of the last item if (levelsUp > 0) { return; } } g.lineStyle(0, 0, 0); if (lineStyle == SOLID) { g.beginFill(lineColor, lineAlpha); } else { var verticalDottedLine:BitmapData = createDottedLine(lineColor, lineAlpha, lineThickness, true); g.beginBitmapFill(verticalDottedLine); } // draw the vertical line g.drawRect(lineX, 0, lineThickness, lineY); // end the fill and start it again otherwise the lines overlap and it create white squares g.endFill(); // draw the horizontal line – only needed on this node (not on any parents) if (levelsUp == 0) { var startX:int = lineX + 1 + int(lineThickness / 2); var endX:int = startX + 11; // 5 dots if (isLastItem) { startX = lineX; } var startY:Number = midY – int(lineThickness / 2); if (lineStyle == SOLID) { g.beginFill(lineColor, lineAlpha); } else { var horizontalDottedLine:BitmapData = createDottedLine(lineColor, lineAlpha, lineThickness, false); g.beginBitmapFill(horizontalDottedLine); } g.drawRect(startX, startY, endX – startX, lineThickness); g.endFill(); } } /** * Creates a BitmapData that is used to renderer a dotted line. * If the vertical parameter is true, then it creates a rectangle bitmap that is * twice as long as it is wide (lineThickness). Otherwise it creates a rectangle * that is twice as wide as it is long. * The first half of the rectangle is filled with the line color (and alpha value), * then second half is transparent. */ private function createDottedLine(lineColor:uint, lineAlpha:Number, lineThickness:Number, vertical:Boolean = true):BitmapData { var w:Number = (vertical ? lineThickness : 2 * lineThickness); var h:Number = (vertical ? 2 * lineThickness : lineThickness); var color32:uint = combineColorAndAlpha(lineColor, lineAlpha); var dottedLine:BitmapData = new BitmapData(w, h, true, 0x00ffffff); // create a dotted bitmap for (var i:int = 0; i < lineThickness; i++) { for (var j:int = 0; j < lineThickness; j++) { dottedLine.setPixel32(i, j, color32); } } return dottedLine; } /** * Combines the color value and the alpha value into a 32 bit uint like #AARRGGBB. */ private function combineColorAndAlpha(color:uint, alpha:Number):uint { // make sure the alpha is a valid number [0-1] if (isNaN(alpha)) { alpha = 1; } else { alpha = Math.max(0, Math.min(1, alpha)); } // convert the [0-1] alpha value into [0-255] var alphaColor:Number = alpha * 255; // bitshift it to come before the color alphaColor = alphaColor << 24; // combine the two values: #AARRGGBB var combined:uint = alphaColor | color; return combined; } private function getColorStyle(propName:String, defaultValue:uint):uint { var color:uint = defaultValue; if (propName != null) { var n:Number = getStyle(propName); if (!isNaN(n)) { color = uint(n); } } return color; } private function getNumberStyle(propName:String, defaultValue:Number):Number { var number:Number = defaultValue; if (propName != null) { var n:Number = getStyle(propName); if (!isNaN(n)) { number = n; } } return number; } } }
