numericaxis.as

拓扑图基于SNMP数据采集模块的设计和实现

package com.yahoo.astra.fl.charts.axes
{
	import com.yahoo.astra.fl.charts.series.ISeries;
	import com.yahoo.astra.fl.utils.UIComponentUtil;
	import com.yahoo.astra.utils.NumberUtil;
	
	import flash.utils.Dictionary;
	
	/**
	 * An axis type representing a numeric range from minimum to maximum
	 * with major and minor divisions.
	 * 
	 * @author Josh Tynjala
	 */
	public class NumericAxis extends BaseAxis implements IAxis, IOriginAxis, IStackingAxis
	{
		
	//--------------------------------------
	//  Static Properties
	//--------------------------------------
	
		/**
		 * A magic number specifying an ideal minimum number of
		 * pixels between each tick/line/label on a major unit.
		 * Used to calculate the major unit if it is not set by
		 * the developer. 
		 */
		private static const IDEAL_PIXELS_BETWEEN_MAJOR_POSITIONS:Number = 70;
		
		/**
		 * A magic number specifying an ideal minimum number of
		 * pixels between each tick/line/label on a minor unit.
		 * Used to calculate the minor unit if it is not set by
		 * the developer. 
		 */
		private static const IDEAL_PIXELS_BETWEEN_MINOR_POSITIONS:Number = 30;
		
	//--------------------------------------
	//  Constructor
	//--------------------------------------
	
		/**
		 * Constructor.
		 */
		public function NumericAxis()
		{
		}

	//--------------------------------------
	//  Properties
	//--------------------------------------
		
		/**
		 * @private
		 * The multiplier used to calculate the position on the renderer from an
		 * axis value.
		 */
		protected var positionMultiplier:Number = 0;
		
		/**
		 * @private
		 * Storage for the minimum value.
		 */
		private var _minimum:Number = 0;
		
		/**
		 * @private
		 * Indicates whether the minimum bound is user-defined or generated by the axis.
		 */
		private var _minimumSetByUser:Boolean = false;
		
		/**
		 * The minimum value displayed on the axis. By default, this value is generated
		 * by the axis itself. If the user defines this value, the axis will skip this
		 * automatic generation. To enable this behavior again, set this property to NaN.
		 */
		public function get minimum():Number
		{
			return this._minimum;
		}
		
		/**
		 * @private
		 */
		public function set minimum(value:Number):void
		{
			this._minimum = value;
			this._minimumSetByUser = !isNaN(value);
		}
	
		/**
		 * @private
		 * Storage for the maximum value.
		 */
		private var _maximum:Number = 100;
		
		/**
		 * @private
		 * Indicates whether the maximum bound is user-defined or generated by the axis.
		 */
		private var _maximumSetByUser:Boolean = false;
		
		/**
		 * The maximum value displayed on the axis. By default, this value is generated
		 * by the axis itself. If the user defines this value, the axis will skip this
		 * automatic generation. To enable this behavior again, set this property to NaN.
		 */
		public function get maximum():Number
		{
			return this._maximum;
		}
		
		/**
		 * @private
		 */
		public function set maximum(value:Number):void
		{
			this._maximum = value;
			this._maximumSetByUser = !isNaN(value);
		}
		
	//-- Units
	
		/**
		 * @private
		 * Storage for the major unit.
		 */
		private var _majorUnit:Number = 10;
		
		/**
		 * @private
		 * Indicates whether the major unit is user-defined or generated by the axis.
		 */
		private var _majorUnitSetByUser:Boolean = false;
		
		/**
		 * The major unit at which new ticks and labels are drawn. By default, this value
		 * is generated by the axis itself. If the user defines this value, the axis will
		 * skip the automatic generation. To enable this behavior again, set this property
		 * to NaN.
		 */
		public function get majorUnit():Number
		{
			return this._majorUnit;
		}
		
		/**
		 * @private
		 */
		public function set majorUnit(value:Number):void
		{
			this._majorUnit = value;
			this._majorUnitSetByUser = !isNaN(value);
		}
	
		/**
		 * @private
		 * Storage for the minor unit.
		 */
		private var _minorUnit:Number = 5;
		
		/**
		 * @private
		 * Indicates whether the minor unit is user-defined or generated by the axis.
		 */
		private var _minorUnitSetByUser:Boolean = false;
		
		/**
		 * The minor unit at which new ticks are drawn. By default, this value
		 * is generated by the axis itself. If the user defines this value, the axis will
		 * skip the automatic generation. To enable this behavior again, set this property
		 * to NaN.
		 */
		public function get minorUnit():Number
		{
			return this._minorUnit;
		}
		
		/**
		 * @private
		 */
		public function set minorUnit(value:Number):void
		{
			this._minorUnit = value;
			this._minorUnitSetByUser = !isNaN(value);
		}
		
		/**
		 * @inheritDoc
		 */
		public function get origin():Object
		{
			var origin:Number = 0;
			if(this.scale == ScaleType.LOGARITHMIC)
			{
				origin = 1;
			}
			
			origin = Math.max(origin, this.minimum);
			origin = Math.min(origin, this.maximum);
			return origin;
		}
		
		/**
		 * @private
		 * Storage for the stackingEnabled property.
		 */
		private var _stackingEnabled:Boolean = false;
		
		/**
		 * @inheritDoc
		 */
		public function get stackingEnabled():Boolean
		{
			return this._stackingEnabled;
		}
		
		/**
		 * @private
		 */
		public function set stackingEnabled(value:Boolean):void
		{
			this._stackingEnabled = value;
		}
	
		/**
		 * @private
		 * Storage for the alwaysShowZero property.
		 */
		private var _alwaysShowZero:Boolean = true;
		
		/**
		 * If true, the axis will attempt to keep zero visible at all times.
		 * If both the minimum and maximum values displayed on the axis are
		 * above zero, the minimum will be reset to zero. If both minimum and
		 * maximum appear below zero, the maximum will be reset to zero. If
		 * the minimum and maximum appear at positive and negative values
		 * respectively, zero is already visible and the axis scale does not
		 * change.
		 * 
		 * <p>This property has no affect if you manually set the minimum and
		 * maximum values of the axis.</p>
		 */
		public function get alwaysShowZero():Boolean
		{
			return this._alwaysShowZero;
		}
		
		/**
		 * @private
		 */
		public function set alwaysShowZero(value:Boolean):void
		{
			this._alwaysShowZero = value;
		}
	
		/**
		 * @private
		 * Storage for the snapToUnits property.
		 */
		private var _snapToUnits:Boolean = true;
		
		/**
		 * If true, the labels, ticks, gridlines, and other objects will snap to
		 * the nearest major or minor unit. If false, their position will be based
		 * on the minimum value.
		 */
		public function get snapToUnits():Boolean
		{
			return this._snapToUnits;
		}
		
		/**
		 * @private
		 */
		public function set snapToUnits(value:Boolean):void
		{
			this._snapToUnits = value;
		}
		
		/**
		 * @private
		 * Storage for the scale property.
		 */
		private var _scale:String = ScaleType.LINEAR;
		
		/**
		 * The type of scaling used to display items on the axis.
		 * 
		 * @see com.yahoo.astra.fl.charts.ScaleType
		 */
		public function get scale():String
		{
			return this._scale;
		}
		
		/**
		 * @private
		 */
		public function set scale(value:String):void
		{
			this._scale = value;
		}
		
		/**
		 * @private
		 */
		private var _dataMinimum:Number = NaN;
		
		/**
		 * @private
		 */
		private var _dataMaximum:Number = NaN;
			
	//--------------------------------------
	//  Public Methods
	//--------------------------------------
	
		/**
		 * @inheritDoc
		 */
		public function valueToLocal(data:Object):Number
		{
			if(data == null)
			{
				//bad data. a properly-designed renderer will not draw this.
				return NaN;
			}
			
			var position:Number = 0;
			
			if(this.scale == ScaleType.LINEAR)
			{
				position = (Number(data) - this.minimum) * this.positionMultiplier;
			}
			else
			{
				var logOfData:Number = Math.log(Number(data));
				var logOfMinimum:Number = Math.log(this.minimum);
				position = (logOfData - logOfMinimum) * this.positionMultiplier;
			}
			
			if(this.reverse)
			{
				position = this.renderer.length - position;
			}
			
			//the vertical axis has its origin on the bottom
			if(this.renderer is ICartesianAxisRenderer && ICartesianAxisRenderer(this.renderer).orientation == AxisOrientation.VERTICAL)
			{
				position = this.renderer.length - position;
			}
			
			return Math.round(position);
		}
	
		/**
		 * @inheritDoc
		 */
		public function stack(top:Object, ...rest:Array):Object
		{
			var numericValue:Number = Number(top);
			var negative:Boolean = false;
			if(numericValue < 0)
			{
				negative = true;
			}
			
			var restCount:int = rest.length;
			for(var i:int = 0; i < restCount; i++)
			{
				var currentValue:Number = Number(rest[i]);
				if(negative && currentValue < 0)
				{
					numericValue += currentValue;
				}
				else if(!negative && currentValue > 0)
				{
					numericValue += currentValue;
				}
			}
			return numericValue;
		}
	
		/**
		 * @inheritDoc
		 */
		public function updateScale(data:Array):void