调用5+ api uploader.createUpload无法暂停上传文件

<template>  
    <view class="page">  
        <progress percent="80" active />  
        {{GethasLogin}}  
        <view class="title">  
            {{title}}  
        </view>  
        <view>{{msg}}</view>  
        <button type="primary" @tap="start">start upload</button>  
        <button type="primary" @tap="pause">pause upload</button>  
        <button type="primary" @tap="resume">resume upload</button>  
        <button type="primary" @tap="abort">abort upload</button>  
        <view class="page-body">  
            <view class="btn-area">  
                <navigator url="/pages/API/action-sheet/action-sheet" hover-class="navigator-hover">  
                    <button type="default">ction-sheet</button>  
                </navigator>  
            </view>  
        </view>  
    </view>  
</template>  

<script>  
    import {  
        mapGetters  
    } from 'vuex';  
    export default {  
        data() {  
            return {  
                title: `this is test tabbar`,  
                msg: '',  
                path: '',  
                task: null  
            }  
        },  
        onShow: function() {  
            console.log(`test onLoad page...`);  
        },  
        methods: {  
            start(){  
                this.createUpload(this.path);  
            },  
            pause(){  
                console.log('===pause===', JSON.stringify(this.task));  
                this.msg = '上传暂停';  
                this.task.pause();  
            },  
            resume(){  
                this.msg = '继续上传中';  
                this.task.resume();  
            },  
            abort(){  
                this.msg = '取消上传';  
                this.task.abort();  
            },  
            previewImage() {  
                plus.nativeUI.previewImage([  
                    "http://img-cdn-qiniu.dcloud.net.cn/icon1.png",  
                    "http://img-cdn-qiniu.dcloud.net.cn/icon2.png",  
                    "http://img-cdn-qiniu.dcloud.net.cn/icon3.png"  
                ]);  
            },  
            createUpload(path) {  
                let that = this;  
                // plus.nativeUI.showWaiting( "上传中..." );  
                that.msg = '上传中';  
                that.task = plus.uploader.createUpload("http://192.168.1.141:7021/xinglan-web/uploadFile/upload", {  
                        method: "POST",  
                        blocksize: 1048576  
                    }, function(t, status) {  
                        console.log(JSON.stringify(t), t.responseText.message);  
                        // 上传完成  
                        if (status == 200) {  
                            plus.nativeUI.alert("Upload success: " + t.url);  
                            that.msg = '上传完成';  
                            // plus.nativeUI.closeWaiting();  
                        } else {  
                            plus.nativeUI.alert("Upload failed: " + status);  
                            console.log('error==', status);  
                            that.msg = '上传出错';  
                        }  
                    }  
                );  
                that.task.addFile(path, {  
                    key: "uploadFile"  
                });  
                that.task.addData( "string_key", "string_value");  
                that.task.addEventListener( "statechanged", function(upload, status){  
                    console.log('==statechanged==', upload.state)  
                    console.log('===status===', status);  
                }, false );  
                that.task.start();  
            },  
            chooseFile() {  
                uni.chooseImage({  
                    success: (chooseImageRes) => {  
                        plus.nativeUI.alert(chooseImageRes.tempFilePaths[0]);  
                        uni.setStorageSync('storage_key','uuid123456');  
                        plus.nativeUI.alert('storage_key='+uni.getStorageSync('storage_key'));  
                    }  
                });  
            }  
        },  
        onNavigationBarButtonTap(e) {  
            let that = this;  
            // 监听原生标题栏按钮点击事件，参数为Object  
            this.title = e.index;  

            // that.chooseFile();  

            // 单选  
            plus.gallery.pick(function(path) {  
                that.path = path;  
                // that.createUpload(path)  
            }, function(e) {  
                console.log("取消选择了");  
                that.path = '';  
            }, {  
                filter: "video"  
            });  
            //多选  
            //          plus.gallery.pick(function(e) {  
            //              for (var i in e.files) {  
            //                  console.log(e.files[i]);  
            //                  plus.nativeUI.alert(e.files[i]);  
            //              }  
            //          }, function(e) {  
            //              console.log("取消选择图片");  
            //          }, {  
            //              filter: "image",  
            //              multiple: true  
            //          });  
            // this.previewImage()  
        }  
    }  
</script>  

<style lang="scss">  
    .page {  
        padding: 10upx;  

        .page-body {  
            // background: blue;  

            .btn-area {  
                font-size: 24upx;  
            }  
        }  
    }  
</style>