Perform the post request manually to be able to send the folder id with it

Modules/Media/Assets/js/components/UploadButton.vue

@@ -20,14 +20,19 @@
             :on-remove="handleRemove"
             :on-success="handleSuccess"
             :file-list="fileList"
-            :headers="requestHeaders"
+            :http-request="uploadFile"
             style="display: inline-block; margin-right: 10px;">
         <el-button size="small" type="primary" style="padding: 11px 9px;">Upload File</el-button>
     </el-upload>
 </template>
 
 <script>
+    import axios from 'axios'
+
     export default {
+        props: {
+            parentId: {type: Number}
+        },
         data() {
             return {
                 fileList: [],
@@ -49,6 +54,16 @@
                 this.$events.emit('fileWasUploaded', response);
                 this.fileList = [];
             },
+            uploadFile(event) {
+                let data = new FormData();
+                data.append('parent_id', this.parentId);
+                data.append('file', event.file);
+                axios.post(route('api.media.store'), data)
+                    .then(response => {
+                        this.fileList = [];
+                        this.$events.emit('fileWasUploaded', response);
+                    });
+            },
             handleRemove() {},
         },
         mounted() {