---
title: Quasar
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pagination_next: demos/desktop/index
sidebar_position: 3
sidebar_custom_props:
  summary: VueJS + Web View
---
import current from '/version.js';
import CodeBlock from '@theme/CodeBlock';
The [NodeJS Module](/docs/getting-started/installation/nodejs) can be imported
from the main entrypoint or any script in the project.
The "Complete Example" creates an app that looks like the screenshots below:
  | iOS | Android | 
|  |  | 
### Integration Details
This demo will use the Quasar ViteJS starter project with VueJS and Cordova.
The complete solution uses `cordova-plugin-file` for file operations.  It can
be installed like any other Cordova plugin:
```bash
cd src-cordova
cordova plugin add cordova-plugin-file
cd ..
```
#### Reading data
The `q-file` component presents an API reminiscent of File Input elements:
```html
```
When binding to the `input` element, the callback receives an `Event` object:
```ts
import { read } from 'xlsx';
// assuming `todos` is a standard VueJS `ref`
async function updateFile(v) { try {
  // `v.target.files[0]` is the desired file object
  const files = (v.target as HTMLInputElement).files;
  if(!files || files.length == 0) return;
  // read first file
  const wb = read(await files[0].arrayBuffer());
  // get data of first worksheet as an array of objects
  const data = utils.sheet_to_json(wb.Sheets[wb.SheetNames[0]]);
  // update state
  todos.value = data.map(row => ({id: row.Index, content: row.Name}));
} catch(e) { console.log(e); } }
```
#### Writing data
The API is shaped like the File and Directory Entries API.  For clarity, since
the code is a "pyramid of doom", the error handlers are omitted:
```ts
import { write } from 'xlsx';
// on iOS and android, `XLSX.write` with type "buffer" returns a `Uint8Array`
const u8: Uint8Array = write(wb, {bookType: "xlsx", type: "buffer"});
// Request filesystem access for persistent storage
window.requestFileSystem(window.PERSISTENT, 0, function(fs) {
  // Request a handle to "SheetJSQuasar.xlsx", making a new file if necessary
  fs.root.getFile("SheetJSQuasar.xlsx", {create: true}, entry => {
    // Request a FileWriter for writing data
    entry.createWriter(writer => {
      // The FileWriter API needs an actual Blob
      const data = new Blob([u8], {type: "application/vnd.ms-excel"});
      // This callback is called if the write is successful
      writer.onwriteend = () => {
        // TODO: show a dialog
      };
      // writer.onerror will be invoked if there is an error in writing
      // write the data
      writer.write(data);
    });
  });
});
```
### Demo
:::note
This demo was tested on an Intel Mac on 2023 April 08. `create-quasar@1.1.2`
was installed during app creation.  The app used Quasar version `2.11.10`.
The iOS simulator runs iOS 16.2 on an iPhone 14 Pro Max.
The Android simulator runs Android 12.0 (S) API 31 on a Pixel 3.
:::
The demo draws from the ViteJS example.  Familiarity with VueJS and TypeScript
is assumed.
0) Ensure all of the dependencies are installed.  Install the CLI globally:
```bash
npm i -g @quasar/cli cordova
```
(you may need to run `sudo npm i -g` if there are permission issues)
1) Create a new app:
```bash
npm init quasar
```
When prompted:
- "What would you like to build?": `App with Quasar CLI`
- "Project folder": `SheetJSQuasar`
- "Pick Quasar version": `Quasar v2 (Vue 3 | latest and greatest)`
- "Pick script type": `Typescript`
- "Pick Quasar App CLI variant": `Quasar App CLI with Vite`
- "Package name": (just press enter, it will use the default `sheetjsquasar`
- "Project product name": `SheetJSQuasar`
- "Project description": `SheetJS + Quasar`
- "Author": (just press enter, it will use your git config settings)
- "Pick a Vue component style": `Composition API`
- "Pick your CSS preprocessor": `None`
- "Check the features needed for your project": Deselect everything
- "Install project dependencies": `No`
2) Install dependencies:
{`\
cd SheetJSQuasar
npm i
npm i --save https://cdn.sheetjs.com/xlsx-${current}/xlsx-${current}.tgz`}
3) Set up Cordova:
```bash
quasar mode add cordova
```
When prompted, enter the app id `org.sheetjs.quasar`.
It will create a new `src-cordova` folder. Continue in that folder:
```bash
cd src-cordova
cordova platform add ios
cordova plugin add cordova-plugin-wkwebview-engine
cordova plugin add cordova-plugin-file
```
:::note pass
If there is an error `Could not load API for iOS project`, it needs to be reset:
```bash
cordova platform rm ios
cordova platform add ios
cordova plugin add cordova-plugin-file
```
:::
Return to the project directory:
```bash
cd ..
```
4) Start the development server:
```bash
quasar dev -m ios
```
:::caution
If the app is blank or not refreshing, delete the app and close the simulator,
then restart the development process.
:::
5) Add the Dialog plugin to `quasar.config.js`:
```js title="quasar.config.js"
    framework: {
      config: {},
// ...
      // Quasar plugins
      // highlight-next-line
      plugins: ['Dialog']
    },
```
6) In the template section of `src/pages/IndexPage.vue`, replace the example
   with a Table, Save button and Load file picker component:
```html title="src/pages/IndexPage.vue"
  
    
    
    
      
      
    
    
  
```
This uses two functions that should be added to the component script:
```ts title="src/pages/IndexPage.vue"
    const meta = ref({
      totalCount: 1200
    });
// highlight-start
    function saveFile() {
    }
    async function updateFile(v: Event) {
    }
    return { todos, meta, saveFile, updateFile };
// highlight-end
  }
});
```
The app should now show two buttons at the bottom:

:::caution
If the app is blank or not refreshing, delete the app and close the simulator,
then restart the development process.
:::
7) Wire up the `updateFile` function:
```ts title="src/pages/IndexPage.vue"
import { defineComponent, ref } from 'vue';
// highlight-start
import { read, write, utils } from 'xlsx';
import { useQuasar } from 'quasar';
// highlight-end
export default defineComponent({
// ...
// highlight-start
    const $q = useQuasar();
    function dialogerr(e: Error) { $q.dialog({title: "Error!", message: e.message || String(e)}); }
// highlight-end
    function saveFile() {
    }
    async function updateFile(v: Event) {
// highlight-start
      try {
        const files = (v.target as HTMLInputElement).files;
        if(!files || files.length == 0) return;
        const wb = read(await files[0].arrayBuffer());
        const data = utils.sheet_to_json(wb.Sheets[wb.SheetNames[0]]);
        todos.value = data.map(row => ({id: row.Index, content: row.Name}));
      } catch(e) { dialogerr(e); }
// highlight-end
    }
```
To test that reading works:
- Download 
- In the simulator, click the Home icon to return to the home screen
- Click on the "Files" icon
- Click and drag `pres.numbers` from a Finder window into the simulator.

- Make sure "On My iPhone" is highlighted and select "Save"
- Click the Home icon again then select the `SheetJSQuasar` app
- Click the "Load" button, then select "Choose File" and select `pres`:

Once selected, the screen should refresh with new contents.
8) Wire up the `saveFile` function:
```ts title="src/pages/IndexPage.vue"
    function saveFile() {
// highlight-start
      /* generate workbook from state */
      const ws = utils.json_to_sheet(todos.value);
      const wb = utils.book_new();
      utils.book_append_sheet(wb, ws, "SheetJSQuasar");
      const u8: Uint8Array = write(wb, {bookType: "xlsx", type: "buffer"});
      const dir: string = $q.cordova.file.documentsDirectory || $q.cordova.file.externalApplicationStorageDirectory;
      /* save to file */
      window.requestFileSystem(window.PERSISTENT, 0, function(fs) {
        try {
          fs.root.getFile("SheetJSQuasar.xlsx", {create: true}, entry => {
            const msg = `File stored at ${dir} ${entry.fullPath}`;
            entry.createWriter(writer => {
              try {
                const data = new Blob([u8], {type: "application/vnd.ms-excel"});
                writer.onwriteend = () => {
                  try {
                    $q.dialog({title: "Success!", message: msg});
                  } catch(e) { dialogerr(e); }
                };
                writer.onerror = dialogerr;
                writer.write(data);
              } catch(e) { dialogerr(e); }
            }, dialogerr);
          }, dialogerr);
        } catch(e) { dialogerr(e) }
      }, dialogerr);
// highlight-end
    }
```
The page should revert to the old contents.
To test that writing works:
- Click "Save File".  You will see a popup with a location:

- Find the file and verify the contents are correct.  Run in a new terminal:
```bash
find ~/Library/Developer/CoreSimulator -name SheetJSQuasar.xlsx |
  while read x; do echo "$x"; npx xlsx-cli "$x"; done
```
Since the contents reverted, you should see
```
SheetJSQuasar
id,content
1,ct1
2,ct2
3,ct3
4,ct4
5,ct5
```
- Use "Load File" to select `pres.numbers` again.  Wait for the app to refresh.
- Click "Save File", then re-run the command:
```bash
find ~/Library/Developer/CoreSimulator -name SheetJSQuasar.xlsx |
  while read x; do echo "$x"; npx xlsx-cli "$x"; done
```
The contents from `pres.numbers` should show up now, with a new header row:
```
SheetJSQuasar
id,content
42,Bill Clinton
43,GeorgeW Bush
44,Barack Obama
45,Donald Trump
46,Joseph Biden
```
**Android**
9) Create the Android project:
```bash
cd src-cordova
cordova platform add android
cd ..
```
10) Start the simulator:
```bash
quasar dev -m android
```
:::note
In local testing, the Quasar build process threw an error:
```
  java.lang.IllegalArgumentException: Unsupported class file major version 63
```
This was resolved by rolling back to Java 1.8
:::
To test that reading works:
- Click and drag `pres.numbers` from a Finder window into the simulator.
- Tap "Load", tap the `≡` icon, tap "Downloads" and select `pres.numbers`.
To test that writing works:
- Tap "Save File".  You will see a popup with a location.
- Pull the file from the simulator and verify the contents:
```bash
adb exec-out run-as org.sheetjs.quasar cat files/files/SheetJSQuasar.xlsx > /tmp/SheetJSQuasar.xlsx
npx xlsx-cli /tmp/SheetJSQuasar.xlsx
```