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Quasar

The NodeJS Module 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:

cd src-cordova
cordova plugin add cordova-plugin-file
cd ..

Reading data

The q-file component presents an API reminiscent of File Input elements:

<q-file label="Load File" filled label-color="orange" @input="updateFile"/>

When binding to the input element, the callback receives an Event object:

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:

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:

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:

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-latest/xlsx-latest.tgz

3) Set up Cordova:

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:

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:

cordova platform rm ios
cordova platform add ios
cordova plugin add cordova-plugin-file

Return to the project directory:

cd ..

4) Start the development server:

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.

Quasar Step 4

5) Add the Dialog plugin to quasar.config.js:

quasar.config.js
      // Quasar plugins
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:

src/pages/IndexPage.vue
    <q-btn-group>
<q-file label="Load File" filled label-color="orange" @input="updateFile"/>
<q-btn label="Save File" @click="saveFile" />
</q-btn-group>
</q-page>
</template>

This uses two functions that should be added to the component script:

src/pages/IndexPage.vue
    const meta = ref<Meta>({
totalCount: 1200
});
function saveFile() {
}
async function updateFile(v) {
}
return { todos, meta, saveFile, updateFile };
}
});

The app should now show two buttons at the bottom:

Quasar Step 6

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:

src/pages/IndexPage.vue
import { defineComponent, ref } from 'vue';
import { read, write, utils } from 'xlsx';
import { useQuasar } from 'quasar';

export default defineComponent({
// ...
const $q = useQuasar();
function dialogerr(e) { $q.dialog({title: "Error!", message: e.message || String(e)}); }
function saveFile() {
}
async function updateFile(v) {
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); }
}

To test that reading works:

  • Download https://sheetjs.com/pres.numbers
  • 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.

Quasar Step 7 save file

  • 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:

Quasar Step 7 load file

Once selected, the screen should refresh with new contents:

Quasar Step 7 new data

8) Wire up the saveFile function:

    function saveFile() {
/* 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);
}

The page should revert to the old contents.

To test that writing works:

  • Click "Save File". You will see a popup with a location:

Quasar Step 8

  • Find the file and verify the contents are correct. Run in a new terminal:
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:

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