[代码]// src/myOpenDataContext/index.js[代码][代码]let sharedCanvas = wx.getSharedCanvas();[代码][代码]let context = sharedCanvas.getContext([代码][代码]"2d"[代码][代码]);[代码] [代码]context.fillStyle = [代码][代码]"#fff"[代码][代码];[代码][代码]context.fillRect(0, 0, 100, 100);[代码] [代码]context.fillText([代码][代码]"获取的数据"[代码][代码], 0, 0);[代码] [代码]//game.js[代码] [代码]let openDataContext = wx.getOpenDataContext();[代码][代码]let sharedCanvas = openDataContext.canvas;[代码]  [代码]let canvas = wx.createCanvas();[代码][代码]let context = canvas.getContext([代码][代码]"2d"[代码][代码]);[代码][代码]context.drawImage(sharedCanvas, 0, 0);[代码] [代码]// new Main();[代码]我想让开放域上的离屏canvas在主域上显示，但是完全没效果，全部是黑色，这是为什么