canvas隐藏时wx.canvasToTempFilePath有时会出现fail:illegal arguments（android手机）

wxml:

<canvas wx:if=’{{!showImage}}’ style=‘width: {{canvasWidth}}px; height: {{canvasHeight}}px’ canvas-id=“canvas”>

js:

…

ctx.draw()

wx.canvasToTempFilePath({

canvasId: ‘canvas’,

success: function (res) {

that.setData({ imageUrl: res.tempFilePath, showImage: true })

},

fail: function (err) {

console.error(‘wx.canvasToTempFilePath fail’, err)

}

})

有时会成功，有时会报错