---
title: Quasar
pagination_prev: demos/static/index
pagination_next: demos/desktop/index
sidebar_position: 3
sidebar_custom_props:
summary: VueJS + Web View
---
The [NodeJS Module](/docs/getting-started/installation/nodejs) can be imported
from the main entrypoint or any script in the project.
This demo will use the Quasar ViteJS starter project with VueJS and Cordova.
### Integration Details
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 2022 August 14. Quasar version `2.7.7`.
The iOS simulator runs iOS 15.5 on an iPhone SE 3rd generation.
:::
The demo draws from the ViteJS example. Familiarity with VueJS and TypeScript
is assumed.
Complete Example (click to show)
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:
```bash
cd SheetJSQuasar
npm i
npm i --save https://cdn.sheetjs.com/xlsx-latest/xlsx-latest.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
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"
// Quasar plugins
// highlight-next-line
plugins: ['Dialog']
```
6) In the template section of `src/pages/IndexPage.vue`, add a Save button and
a Load file picker component at the bottom of the page:
```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) {
}
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) { $q.dialog({title: "Error!", message: e.message || String(e)}); }
// highlight-end
function saveFile() {
}
async function updateFile(v) {
// 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:
```js
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"});
/* save to file */
window.requestFileSystem(window.PERSISTENT, 0, function(fs) {
try {
fs.root.getFile("SheetJSQuasar.xlsx", {create: true}, entry => {
const msg = `File stored at ${$q.cordova.file.documentsDirectory} ${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
```