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Elements
Classes

Element Legend

JXG.GeometryElement
   ↳ JXG.Legend
         ↳ Legend

Creates a legend for a chart element. Parameter is a pair of coordinates. The label names and the label colors are supplied in the attributes:



Defined in: chart.js.
Extends JXG.Legend.

Element Summary
Constructor Attributes Constructor Name and Description
 
Legend
Attributes Summary
Field Attributes Field Name and Description
 
colors
(Circular) array of label colors.
 
frozen
The element is fixed and can not be dragged around.
 
labels
Label names of a legend element.
 
lineLength
Length of line in one legend entry
 
rowHeight
Height (in px) of one legend entry
 
strokeOpacity
(Circular) array of opacity for legend line stroke color for one legend entry.
 
strokeWidth
Height (in px) of one legend entry
 
style
Default style of a legend element.
Methods borrowed from class JXG.Legend:
drawVerticalLegend
Methods borrowed from class JXG.GeometryElement:
_set, addChild, addDescendants, addParents, addParentsFromJCFunctions, addRotation, addTicks, addTransform, animate, bounds, clearTrace, cloneToBackground, countChildren, createGradient, createLabel, draggable, eval, evalVisProp, formatNumberLocale, fullUpdate, generatePolynomial, getAttribute, getAttributes, getLabelAnchor, getName, getParents, getProperty, getSnapSizes, getTextAnchor, getType, handleSnapToGrid, hasPoint, hide, hideElement, noHighlight, normalize, prepareUpdate, remove, removeAllTicks, removeChild, removeDescendants, removeTicks, resolveShortcuts, setArrow, setAttribute, setDash, setDisplayRendNode, setLabel, setLabelText, setName, setParents, setPosition, setPositionDirectly, setProperty, show, showElement, snapToPoints, update, updateRenderer, updateVisibility, useLocale
Events borrowed from class JXG.GeometryElement:
attribute, attribute:key, down, drag, keydrag, mousedown, mousedrag, mousemove, mouseout, mouseover, mouseup, move, out, over, pendown, pendrag, penup, touchdown, touchdrag, touchup, up
Element Detail
Legend
This element has no direct constructor. To create an instance of this element you have to call JXG.Board#create with type "legend".

Possible parent array combinations are:
{Number} x

Horizontal coordinate of the left top point of the legend


{Number} y

Vertical coordinate of the left top point of the legend


Throws:
{Exception}
If the element cannot be constructed with the given parent objects an exception is thrown.
Examples:
var board = JXG.JSXGraph.initBoard('jxgbox', {axis:true,boundingbox:[-4,48.3,12.0,-2.3]});
var x       = [-3,-2,-1,0,1,2,3,4,5,6,7,8];
var dataArr = [4,7,7,27,33,37,46,22,11,4,1,0];

colors = ['green', 'yellow', 'red', 'blue'];
board.create('chart', [x,dataArr], {chartStyle:'bar', width:1.0, labels:dataArr, colors: colors} );
board.create('legend', [8, 45], {labels:dataArr, colors: colors, strokeWidth:5} );



				
				
  var inputFun, cf = [], cf2 = [], niveaunum,
    niveauline = [], niveauopac = [],legend;

  inputFun = "x^2/2-2*x*y+y^2/2";
  niveauline = [-3,-2,-1,-0.5, 0, 1,2,3];
  niveaunum = niveauline.length;
  for (let i = 0; JXG.Math.lt(i, niveaunum); i++) {
    let niveaui = niveauline[i];
    niveauopac.push(((i + 1) / (niveaunum + 1)));
    cf.push(board.create("implicitcurve", [
      inputFun + "-(" + niveaui.toFixed(2) + ")", [-2, 2], [-2, 2]], {
      strokeWidth: 2,
      strokeColor: JXG.palette.red,
      strokeOpacity: niveauopac[i],
      needsRegularUpdate: false,
      name: "niveau"+i,
      visible: true
    }));
  }
  legend = board.create('legend', [-1.75, 1.75], {
    labels: niveauline,
    colors: [cf[0].visProp.strokecolor],
    strokeOpacity: niveauopac,
    linelength: 0.2,
    frozen:true
  }
  );





				
                

				


			

			


			
				

    				 Attribute Detail
				

				
					 
					


					{Array}
					colors

					

					

						(Circular) array of label colors.
						
							

							Defined in:  options.js.
						
						
					


					

						
						
						
						
							

							
Default Value:

							

								"['#B02B2C', '#3F4C6B', '#C79810', '#D15600', '#FFFF88', '#c3d9ff', '#4096EE', '#008C00']"
							

							

						

					

				
					 
					


					{Boolean}
					frozen

					

					

						The element is fixed and can not be dragged around. The legend will even stay at its position on zoom and
moveOrigin events.
						
							

							Defined in:  options.js.
						
						
					


					

						
						
						
							

							
See:

							
							
JXG.GeometryElement#frozen

							
							

						
						
							

							
Default Value:

							

								false
							

							

						

					

				
					 
					


					{Array}
					labels

					

					

						Label names of a legend element.
						
							

							Defined in:  options.js.
						
						
					


					

						
						
						
						
							

							
Default Value:

							

								"['1', '2', '3', '4', '5', '6', '7', '8']"
							

							

						

					

				
					 
					


					{Number}
					lineLength

					

					

						Length of line in one legend entry
						
							

							Defined in:  options.js.
						
						
					


					

						
						
						
						
							

							
Default Value:

							

								1
							

							

						

					

				
					 
					


					{Number}
					rowHeight

					

					

						Height (in px) of one legend entry
						
							

							Defined in:  options.js.
						
						
					


					

						
						
						
						
							

							
Default Value:

							

								20
							

							

						

					

				
					 
					


					{Array}
					strokeOpacity

					

					

						(Circular) array of opacity for legend line stroke color for one legend entry.
						
							

							Defined in:  options.js.
						
						
					


					

						
						
						
						
							

							
Default Value:

							

								[1]
							

							

						

					

				
					 
					


					{Number}
					strokeWidth

					

					

						Height (in px) of one legend entry
						
							

							Defined in:  options.js.
						
						
					


					

						
						
						
						
							

							
Default Value:

							

								5
							

							

						

					

				
					 
					


					{String}
					style

					

					

						Default style of a legend element. The only possible value is 'vertical'.
						
							

							Defined in:  options.js.
						
						
					


					

						
						
						
						
							

							
Default Value:

							

								'vertical'
							

							

						

					
				
			


			


			


			

			


			
                
                

                    Attributes borrowed from other Elements
                


                

                
Attributes borrowed from class JXG.GeometryElement: 
aria, cssClass, dash, dashScale, draft, dragToTopOfLayer, element3D, fillColor, fillOpacity, fixed, gradient, gradientAngle, gradientCX, gradientCY, gradientEndOffset, gradientFR, gradientFX, gradientFY, gradientR, gradientSecondColor, gradientSecondOpacity, gradientStartOffset, highlight, highlightCssClass, highlightFillColor, highlightFillOpacity, highlightStrokeColor, highlightStrokeOpacity, highlightStrokeWidth, isLabel, layer, lineCap, needsRegularUpdate, nonnegativeOnly, precision, priv, rotatable, scalable, shadow, snapToGrid, strokeColor, tabindex, trace, traceAttributes, transitionDuration, transitionProperties, visible, withLabel

                

                

                


				
				

					Fields borrowed from other Elements
				


				

				
Fields borrowed from class JXG.GeometryElement: 
_org_type, _pos, ancestors, baseElement, board, childElements, descendants, dump, elementClass, elType, hasLabel, highlighted, id, inherits, isDraggable, isReal, lastDragTime, methodMap, mouseover, name, needsUpdate, notExistingParents, numTraces, parents, quadraticform, rendNode, stdform, subs, symbolic, traces, transformations, type, visProp, visPropCalc

				

				

				

				
				

					Methods borrowed from other Elements
				

				

				
Methods borrowed from class JXG.Legend: 
drawVerticalLegend
Methods borrowed from class JXG.GeometryElement: 
_set, addChild, addDescendants, addParents, addParentsFromJCFunctions, addRotation, addTicks, addTransform, animate, bounds, clearTrace, cloneToBackground, countChildren, createGradient, createLabel, draggable, eval, evalVisProp, formatNumberLocale, fullUpdate, generatePolynomial, getAttribute, getAttributes, getLabelAnchor, getName, getParents, getProperty, getSnapSizes, getTextAnchor, getType, handleSnapToGrid, hasPoint, hide, hideElement, noHighlight, normalize, prepareUpdate, remove, removeAllTicks, removeChild, removeDescendants, removeTicks, resolveShortcuts, setArrow, setAttribute, setDash, setDisplayRendNode, setLabel, setLabelText, setName, setParents, setPosition, setPositionDirectly, setProperty, show, showElement, snapToPoints, update, updateRenderer, updateVisibility, useLocale

				

				

                

                
   				

    				Events borrowed from other Elements
                

                

                
Events borrowed from class JXG.GeometryElement: 
attribute, attribute:key, down, drag, keydrag, mousedown, mousedrag, mousemove, mouseout, mouseover, mouseup, move, out, over, pendown, pendrag, penup, touchdown, touchdrag, touchup, up

                

                

            

		




		

			
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