canvas 圓形進度條

"canvas" width=

"800" height=
"800" style=
"border:1px solid #ccc"
>
<
/canvas>
const can = document.
getelementbyid
('canvas');
const van = can.
getcontext
('2d');
let currentdeg =0;
// 度從0開始
// 先繪製背景，這裡只繪製一次，跟水平進度條不一樣呢
drawcircle()
;drawarc
(currentdeg++);
function
drawarc
(deg),10
)}}function
drawcircle()
<
/script>

"canvas" width=

"500" height=
"500" style=
"background:#000;"
>
<
/canvas>
window.
onload
=function()
//繪製白色外圈
function
whitecircle()
//百分比文字繪製
function
text
(n)//動畫迴圈
(function
drawframe()
());
}

="process" width=

"48px" height=
"48px"
>61%
<
/canvas>
function
drawprocess()

="time-graph"

>
"time-graph-canvas" width=
"160" height=
"160"
>
<
/canvas>
<
/div>
.time-graph 
#time-graph-canvas 
drawmain
(drawing_elem, percent, forecolor, bgcolor)
//繪製運動圓環
function
foregroundcircle
(n)//繪製文字
function
text
(n)//執行動畫
(function
drawframe()
());
},var time_canvas = document.
getelementbyid
("time-graph-canvas");
this
.drawmain
(time_canvas,70,
"#85d824"
,"#eef7e4");
var weather_canvas = document.
getelementbyid
("weather-graph-canvas");
this
.drawmain
(weather_canvas,90,
"#2ba0fb"
,"#e5f1fa"
);

"runcanvas" id=

"runcanvas"
class
='canvas'
>
<
/canvas>
const ctx2 = wx.
createcanvascontext
(id)
;wx.
createselectorquery()
.select
('#'
+id)
.boundingclientrect
(function
(rect)).
exec()
;run
(c, w, h)
,canvastap
(start, end, time, w, h)
that.
run(start, w, h)
;//呼叫run方法
settimeout
(function()
, time);}
,

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