按照官方教程说的主屏绘制sharedCanvas的方式 开发者工具出现警告

An unsecure canvas can't take an secure canvas as arugment of drawImage When using subcontext

看意思是 不安全的 canvas 不能携带安全canvas作为参数

let canvas = wx.createCanvas()

let ctx   = canvas.getContext('2d')

let open_context = wx.getOpenDataContext()

let shared_canvas = open_context.canvas

ctx.clearRect(0, 0, canvas.width, canvas.height)

ctx.drawImage(shared_canvas, 0, 0)

主要是最后一步 ctx.drawImage(shared_canvas, 0, 0)

只能通过这种方式把离屏canvas绘制到上屏canvas吧？