Introduce more events (VPU/Apps/Signature#1)

packages/file-handling/src/demo.js

@@ -24,7 +24,7 @@ class FileUploadDemo extends LitElement {
         this.updateComplete.then(() => {
             this.shadowRoot.querySelectorAll('vpu-fileupload')
                 .forEach(element => {
-                    element.addEventListener('vpu-fileupload-finished', this.addLogEntry.bind(this));
+                    element.addEventListener('vpu-fileupload-file-finished', this.addLogEntry.bind(this));
                 });
         });
     }

packages/file-handling/src/vpu-fileupload.js

@@ -107,8 +107,14 @@ class VPUFileUpload extends VPULitElement {
     async handleFiles(files) {
         console.log('handleFiles: files.length = ' + files.length);
 
+        this.dispatchEvent(new CustomEvent("vpu-fileupload-all-start",
+            { "detail": {}, bubbles: true, composed: true }));
+
         // we need to wait for each upload until we start the next one
         await this.asyncForEach(files, async (file) => this.uploadFile(file));
+
+        this.dispatchEvent(new CustomEvent("vpu-fileupload-all-finished",
+            { "detail": {}, bubbles: true, composed: true }));
     }
 
     async sendFinishedEvent(response, file, sendFile = false) {
@@ -132,15 +138,25 @@ class VPUFileUpload extends VPULitElement {
             data.file = file;
         }
 
-        const event = new CustomEvent("vpu-fileupload-finished", { "detail": data, bubbles: true, composed: true });
+        const event = new CustomEvent("vpu-fileupload-file-finished", { "detail": data, bubbles: true, composed: true });
         this.dispatchEvent(event);
     }
 
+    sendStartEvent(file) {
+        let data =  {
+            filename: file.name,
+        };
+
+        this.dispatchEvent(new CustomEvent("vpu-fileupload-file-start",
+            { "detail": data, bubbles: true, composed: true }));
+    }
+
     /**
      * @param file
      * @returns {Promise<void>}
      */
     async uploadFile(file) {
+        this.sendStartEvent(file);
         let url = this.url;
         let formData = new FormData();