uni-app中微信小程序的addGroundOverlay方法的使用问题

uni-app中微信小程序的addGroundOverlay方法加载图片图层回调函数都显示成功了，真机上测试还是没有显示图层

            this.mapCtx = wx.createMapContext('map');
            this.mapCtx.addGroundOverlay({
                id:1,
                src:'https://mapapi.qq.com/web/lbs/javascriptGL/demo/img/bg.jpg',
                zIndex:999,
                bounds:{
                    northEast: {
                      latitude:'39.995685',
                      longitude: '116.737649'
                    },
                    southWest: {
                      latitude: '39.876225',
                      longitude: '116.251341'
                    }
                },
                success: res => {
                        console.log('成功',res)
                },
                fail: err => {
                    console.log("失败：", err)
                },
            })