在使用camera拍照后调用draw和canvasToTempFilePath后回调里面可以看到有照片，但是显示在页面上的时候image为空白 开发者工具使用camera拍照后拿到的照片无法显示，真机可以显示 调试基础库为2.12.2 代码片段如下： _this.ctx.takePhoto({       quality: 'high',       success: (res) => {         let tempImagePath = res.tempImagePath;         let cas = wx.createCanvasContext('canvas-' + _this.data.type,this);         let picWidth = _this.data.width - 2 * _this.data.gap[_this.data.type],           picHeight = _this.data.width - 2 * _this.data.gap[_this.data.type],           x,           y;         if (_this.data.type != 'peo') {           x = _this.data.gap[_this.data.type] * 0.625;           y = _this.data.gap[_this.data.type] * 0.625;           picWidth = picWidth * 1.59 * 0.625;           picHeight = picHeight * 0.625;           cas.scale(0.625, 0.625);           cas.translate(0, _this.data.width);           cas.rotate((270 * Math.PI) / 180);           cas.drawImage(tempImagePath,0,0,_this.data.width,_this.data.height);         } else {           x = 0;           y = 70;           cas.drawImage(             tempImagePath,             0,             0,             _this.data.width,             _this.data.height           );         }         cas.draw(false,            () => {             console.log('draw done')             setTimeout(() => {               wx.canvasToTempFilePath({                 canvasId: 'canvas-' + _this.data.type,                 x: x,                 y: y,                 width: picWidth,                 height: picHeight,                 destWidth: picWidth * 3,                 destHeight: picHeight * 3,                 success: (result) => {                   console.log('toTempFile done',result)                   let tempPath = result.tempFilePath,                     img = 'imgList.' + _this.data.type;                   if (_this.data.type != 'peo') {                     _this.ocrIden(_this.data.type, tempPath);                   } else {                     _this.setData({                       showPoup: false,                       [img]: tempPath,                     });                     wx.hideLoading({});                   }                   if (                     _this.data.imgList.peo &&                     _this.data.imgList.idcardFront &&                     _this.data.imgList.idcardBack                   ) {                     _this.setData({                       disabled: false,                     });                   }                 },                 fail: (res) => {                   console.log('fail');                 },               })             },1000)           }         );       },       fail: (err) => {         console.log(err);       },     });