dojo_app/js/library/dojox/dgauges/RectangularValueIndicator.js

define(["dojo/_base/declare", "./ScaleIndicatorBase", "dojox/gfx", "dojo/_base/event", "dojo/dom-geometry"],
	function(declare, ScaleIndicatorBase, gfx, eventUtil, domGeom){
	return declare("dojox.dgauges.RectangularValueIndicator", ScaleIndicatorBase, {
		// summary:
		//		The rectangular value indicator, typically used for creating markers or thumbs.

		// paddingLeft: Number
		//		The left padding.
		paddingLeft: 0,
		// paddingTop: Number
		//		The top padding.
		paddingTop: 0,
		// paddingRight: Number
		//		The right padding.
		paddingRight: 0,
		// paddingBottom: Number
		//		The bottom padding.
		paddingBottom: 0,

		
		constructor: function(){
			this.addInvalidatingProperties(["paddingTop", "paddingLeft", "paddingRight", "paddingBottom"]);
		},
		
		indicatorShapeFunc: function(group, indicator){
			// summary:
			//		Draws the indicator.
			// group: dojox/gfx/Group
			//		A GFX group for drawing. The indicator is always centered horizontally and is
			//		automatically rotated if the scale is vertical.
			// indicator: dojox/dgauges/IndicatorBase
			//		A reference to this indicator.
			// returns: dojox/gfx/shape.Shape
			//		A GFX shape retrievable using the getIndicatorRenderer method of the associated scale. 
			return group.createPolyline([0, 0, 10, 0, 0, 10, -10, 0, 0, 0]).setStroke({
					color: "black",
					width: 1
				});
		},
				
		refreshRendering: function(){
			this.inherited(arguments);

			// get position corresponding to the value
			var v = isNaN(this._transitionValue) ? this.value : this._transitionValue;
			var pos = this.scale.positionForValue(v);
			
			// computes offsets to move the indicator
			var dx = 0, dy = 0;
			var angle = 0;
			if(this.scale._gauge.orientation == "horizontal"){
				dx = pos;
				dy = this.paddingTop;
			}else{
				dx = this.paddingLeft;
				dy = pos;
				angle = 90;
			}
			
			// translate the indicator
			
			this._gfxGroup.setTransform([{
				dx: dx,
				dy: dy
			}, gfx.matrix.rotateg(angle)]);
		},
		
		_onMouseDown: function(event){
			// summary:
			//		Internal method.
			// tags:
			//		private
			this.inherited(arguments);
			var np = domGeom.position(this.scale._gauge.domNode, true);
			this.set("value", this.scale.valueForPosition({x: event.pageX - np.x, y: event.pageY - np.y}));

			// prevent the browser from selecting text
			eventUtil.stop(event);
		},
		
		_onMouseMove: function(event){
			// summary:
			//		Internal method.
			// tags:
			//		private
			this.inherited(arguments);
			
			var np = domGeom.position(this.scale._gauge.domNode, true);
			this.set("value", this.scale.valueForPosition({x: event.pageX - np.x, y: event.pageY - np.y}));
		}
	})
});