javascript - How to get rid of old data and of old graph in Chart.js? -


i'm using chart.js make graph.

i encounter problem when use graph. old graph old values not gone when hover cursor on graph. according doc, tried use .destroy() or .clear() rid of old data, doesn't work.

here following codes:

<!doctype html>  <html>  <head>  	<title>hp mp</title>  	<meta charset="utf-8">  	<script src="https://cdnjs.cloudflare.com/ajax/libs/chart.js/2.1.3/chart.min.js"></script>  </head>    <body onload="hpmpgraph()">  	<script>  		function hpmpgraph() {  			var hp = document.hpmpform.hp.value,  				mp = document.hpmpform.mp.value,  				ctx = document.getelementbyid('hpmpratio').getcontext('2d');  				  			var	data = {  				labels: ["hp","mp"],  				datasets:   					[{  						data: [hp,mp],  						backgroundcolor: ["#ef0000","#0000ef"],  						hoverbackgroundcolor: ["#ff0000","#0000ff"]  					}]  			};  			var options = {};    			var mypiechart = new chart(ctx, {  				type: 'pie',  				data: data,  				options: options  			});  		}  	</script>    	<h1>hp & mp</h1>  	<form name=hpmpform method=post>  		hp : <input type="text" name="hp" value="100"><br>  		mp : <input type="text" name="mp" value="100"><br>  		<button type="button" onclick="hpmpgraph();">click</button>  		<h2>pie graph</h2>  		<canvas id="hpmpratio" height="50"></canvas>  	</form>  </body>  </html>

hp , mp both set @ 100. try set 1000 hp. put cursor on graph , move in circle. sometime, old graph show up.

you should not recreate chart since not allowed in v2, instead need replace data:

<!doctype html>  <html>  <head>  	<title>hp mp</title>  	<meta charset="utf-8">  	<script src="https://cdnjs.cloudflare.com/ajax/libs/chart.js/2.1.3/chart.min.js"></script>  </head>    <body onload="hpmpgraph()">  	<script>    	var mypiechart = null          var config = {options:{},type:'pie'}  		function hpmpgraph() {  			var hp = document.hpmpform.hp.value,  				mp = document.hpmpform.mp.value,  				ctx = document.getelementbyid('hpmpratio').getcontext('2d');  			                          config.data = {  				labels: ["hp","mp"],  				datasets:   					[{  						data: [hp,mp],  						backgroundcolor: ["#ef0000","#0000ef"],  						hoverbackgroundcolor: ["#ff0000","#0000ff"]  					}]  			};  			if(mypiechart == null){                              mypiechart = new chart(ctx, config);                          }else{                              mypiechart.update()                          }                   		}  	</script>    	<h1>hp & mp</h1>  	<form name=hpmpform method=post>  		hp : <input type="text" name="hp" value="100"><br>  		mp : <input type="text" name="mp" value="100"><br>  		<button type="button" onclick="hpmpgraph();">click</button>  		<h2>pie graph</h2>  		<canvas id="hpmpratio" height="50"></canvas>  	</form>  </body>  </html>

<!doctype html>  <html>  <head>  	<title>hp mp</title>  	<meta charset="utf-8">  	<script src="https://cdnjs.cloudflare.com/ajax/libs/chart.js/2.1.3/chart.min.js"></script>  </head>    <body onload="hpmpgraph()">  	<script>  		function hpmpgraph() {  			var hp = document.hpmpform.hp.value,  				mp = document.hpmpform.mp.value,  				ctx = document.getelementbyid('hpmpratio').getcontext('2d');  				  			var	data = {  				labels: ["hp","mp"],  				datasets:   					[{  						data: [hp,mp],  						backgroundcolor: ["#ef0000","#0000ef"],  						hoverbackgroundcolor: ["#ff0000","#0000ff"]  					}]  			};  			var options = {};    			var mypiechart = new chart(ctx, {  				type: 'pie',  				data: data,  				options: options  			});  		}  	</script>    	<h1>hp & mp</h1>  	<form name=hpmpform method=post>  		hp : <input type="text" name="hp" value="100"><br>  		mp : <input type="text" name="mp" value="100"><br>  		<button type="button" onclick="hpmpgraph();">click</button>  		<h2>pie graph</h2>  		<canvas id="hpmpratio" height="50"></canvas>  	</form>  </body>  </html>


-

Comments

Post a Comment

Popular posts from this blog

PySide and Qt Properties: Connecting signals from Python to QML -

i trying run simple pyside appliccation design made in qml. call function in qml python in separated thread. i have following qml view: import qt 4.7 rectangle { visible: true width: 100; height: 100 color: "lightgrey" text { id: datestr objectname: "datestr" x: 10 y: 10 text: "init text" font.pixelsize: 12 function updatedata(text) { datestr.text = qstr(text) console.log("you said: " + text) } } } here application: some imports.... #!/usr/bin/python import sys import time pyside import qtdeclarative, qtcore pyside.qtgui import qapplication pyside.qtdeclarative import qdeclarativeview the qthread worker.... #worker thread class worker(qtcore.qthread): updateprogress = qtcore.signal(int) def __init__(self, child): qtcore.qthread.__init__(self) self.child = child def run(self):
Read more

c# - DevExpress.Wpf.Grid.InfiniteGridSizeException was unhandled -

Image
when using devexpress, see error: devexpress.wpf.grid.infinitegridsizeexception unhandled message="by default, infinite grid height not allowed since grid rows rendered , hence grid work slowly. fix issue, should place grid container give finite height grid, or should manually specify grid's height or maxheight. note can avoid exception setting gridcontrol.allowinfinitegridsize static property true, in case grid run slowly." the problem dxgrid has infinite height. to fix, set height non-infinite. snoop absolutely invaluable this: if "height" xaml element infinite (i.e. 0 or nan ), can set using one of following: option 1: height="{binding path=actualheight, relativesource={relativesource mode=findancestor, ancestortype=uielement}}" option 2: verticalalignment="stretch" option 3: height="auto" hint: use verticalalignment="stretch" if child of grid <rowdefinition height=
Read more

scala - 'wrong top statement declaration' when using slick in IntelliJ -

Image
i'm porting project scala 2.9 2.10, therefore have use slick instead of scalaquery. i'm using slick 2.1.0 since supports ms access. according this tutorial , upgrade guide changed robs object class , added val robs : why error message wrong top statement declaration , how rid of it? edit: i'm new scala... according this question seems can't put val outside of methods or classes, right? code above directly in packge. right approach slick then? should move code in class or trait? according this changed val robs = tablequery[robs] to object robs extends tablequery(new robs(_)) {} . no warnings or errors anymore. :)
Read more