**Coding level** : Intermediate  

**Duration** : 30 minutes  

**Project type**: Google Workspace add-on

## Objectives

- Understand what the solution does.
- Understand what the Apps Script services do within the solution.
- Set up the script.
- Run the script.

## About this solution

With this solution, you can translate text from within Google Docs,
Sheets, and Slides.

![The Translate Google Workspace add-on](https://developers.google.com/static/workspace/add-ons/images/translate.png)

![The Translate Google Workspace add-on](https://developers.google.com/static/workspace/add-ons/images/translate.png)

### How it works

When you select text in
Docs, Sheets, or
Slides and click **Get Selection** in the
add-on, the script copies the text into the
add-on, translates it and displays the translated text.

By default, the script detects the source language and translates the text to
English. You can edit the source and target languages.

### Apps Script services

This solution uses the following services:

- [Card service](https://developers.google.com/apps-script/reference/card-service)--Creates the user interface of the add-on.
- [Language service](https://developers.google.com/apps-script/reference/language)--Translates the text using Google Translate.

## Prerequisites

To use this sample, you need the following prerequisites:

- A Google Account (Google Workspace accounts might require administrator approval).
- A web browser with access to the internet.

## Set up the script

### Create the Apps Script project

1. Click the following button to open the **Translate** Apps Script
   project.

   [Open the project](https://script.google.com/d/1IggZ-88Yak6qy-Qlu9oiMVHrAgvR5oP76WvlcqNK2bZlWgGF_eXK1_lb/edit?usp=sharing)

2. Click **Overview** .

3. On the overview page, click Make a copy ![The icon for making a copy](https://fonts.gstatic.com/s/i/short-term/release/googlesymbols/file_copy/default/24px.svg).

### Install a test deployment

1. In your copied Apps Script project, click **Editor** .
2. Open the `Code.gs` file and click **Run**. When prompted, authorize the script.
3. Click **Deploy** \> **Test deployments**.
4. Click **Install** \> **Done**.

## Run the script

1. Open a file in [Google Docs](https://docs.google.com/document/u/0/), [Sheets](https://docs.google.com/spreadsheets/u/0/) or [Slides](https://docs.google.com/presentation/u/0/?tgif=d), or create a new one.
2. On the right sidebar open the Translate add-on .
3. If prompted, authorize the add-on.
4. Select text in your file.
5. In the add-on, click **Get Selection** \> **Translate**.

## Review the code

To review the Apps Script code for this solution, click
**View source code**:

#### View source code

### Code.gs

```
const DEFAULT_INPUT_TEXT = '';
const DEFAULT_OUTPUT_TEXT = '';
const DEFAULT_ORIGIN_LAN = ''; // Empty string means detect langauge
const DEFAULT_DESTINATION_LAN = 'en' // English

const LANGUAGE_MAP =
  [
    { text: 'Detect Language', val: '' },
    { text: 'Afrikaans', val: 'af' },
    { text: 'Albanian', val: 'sq' },
    { text: 'Amharic', val: 'am' },
    { text: 'Arabic', val: 'ar' },
    { text: 'Armenian', val: 'hy' },
    { text: 'Azerbaijani', val: 'az' },
    { text: 'Basque', val: 'eu' },
    { text: 'Belarusian', val: 'be' },
    { text: 'Bengali', val: 'bn' },
    { text: 'Bosnian', val: 'bs' },
    { text: 'Bulgarian', val: 'bg' },
    { text: 'Catalan', val: 'ca' },
    { text: 'Cebuano', val: 'ceb' },
    { text: 'Chinese (Simplified)', val: 'zh-CN' },
    { text: 'Chinese (Traditional)', val: 'zh-TW' },
    { text: 'Corsican', val: 'co' },
    { text: 'Croatian', val: 'hr' },
    { text: 'Czech', val: 'cs' },
    { text: 'Danish', val: 'da' },
    { text: 'Dutch', val: 'nl' },
    { text: 'English', val: 'en' },
    { text: 'Esperanto', val: 'eo' },
    { text: 'Estonian', val: 'et' },
    { text: 'Finnish', val: 'fi' },
    { text: 'French', val: 'fr' },
    { text: 'Frisian', val: 'fy' },
    { text: 'Galician', val: 'gl' },
    { text: 'Georgian', val: 'ka' },
    { text: 'German', val: 'de' },
    { text: 'Greek', val: 'el' },
    { text: 'Gujarati', val: 'gu' },
    { text: 'Haitian Creole', val: 'ht' },
    { text: 'Hausa', val: 'ha' },
    { text: 'Hawaiian', val: 'haw' },
    { text: 'Hebrew', val: 'he' },
    { text: 'Hindi', val: 'hi' },
    { text: 'Hmong', val: 'hmn' },
    { text: 'Hungarian', val: 'hu' },
    { text: 'Icelandic', val: 'is' },
    { text: 'Igbo', val: 'ig' },
    { text: 'Indonesian', val: 'id' },
    { text: 'Irish', val: 'ga' },
    { text: 'Italian', val: 'it' },
    { text: 'Japanese', val: 'ja' },
    { text: 'Javanese', val: 'jv' },
    { text: 'Kannada', val: 'kn' },
    { text: 'Kazakh', val: 'kk' },
    { text: 'Khmer', val: 'km' },
    { text: 'Korean', val: 'ko' },
    { text: 'Kurdish', val: 'ku' },
    { text: 'Kyrgyz', val: 'ky' },
    { text: 'Lao', val: 'lo' },
    { text: 'Latin', val: 'la' },
    { text: 'Latvian', val: 'lv' },
    { text: 'Lithuanian', val: 'lt' },
    { text: 'Luxembourgish', val: 'lb' },
    { text: 'Macedonian', val: 'mk' },
    { text: 'Malagasy', val: 'mg' },
    { text: 'Malay', val: 'ms' },
    { text: 'Malayalam', val: 'ml' },
    { text: 'Maltese', val: 'mt' },
    { text: 'Maori', val: 'mi' },
    { text: 'Marathi', val: 'mr' },
    { text: 'Mongolian', val: 'mn' },
    { text: 'Myanmar (Burmese)', val: 'my' },
    { text: 'Nepali', val: 'ne' },
    { text: 'Norwegian', val: 'no' },
    { text: 'Nyanja (Chichewa)', val: 'ny' },
    { text: 'Pashto', val: 'ps' },
    { text: 'Persian', val: 'fa' },
    { text: 'Polish', val: 'pl' },
    { text: 'Portuguese (Portugal, Brazil)', val: 'pt' },
    { text: 'Punjabi', val: 'pa' },
    { text: 'Romanian', val: 'ro' },
    { text: 'Russian', val: 'ru' },
    { text: 'Samoan', val: 'sm' },
    { text: 'Scots Gaelic', val: 'gd' },
    { text: 'Serbian', val: 'sr' },
    { text: 'Sesotho', val: 'st' },
    { text: 'Shona', val: 'sn' },
    { text: 'Sindhi', val: 'sd' },
    { text: 'Sinhala (Sinhalese)', val: 'si' },
    { text: 'Slovak', val: 'sk' },
    { text: 'Slovenian', val: 'sl' },
    { text: 'Somali', val: 'so' },
    { text: 'Spanish', val: 'es' },
    { text: 'Sundanese', val: 'su' },
    { text: 'Swahili', val: 'sw' },
    { text: 'Swedish', val: 'sv' },
    { text: 'Tagalog (Filipino)', val: 'tl' },
    { text: 'Tajik', val: 'tg' },
    { text: 'Tamil', val: 'ta' },
    { text: 'Telugu', val: 'te' },
    { text: 'Thai', val: 'th' },
    { text: 'Turkish', val: 'tr' },
    { text: 'Ukrainian', val: 'uk' },
    { text: 'Urdu', val: 'ur' },
    { text: 'Uzbek', val: 'uz' },
    { text: 'Vietnamese', val: 'vi' },
    { text: 'Welsh', val: 'cy' },
    { text: 'Xhosa', val: 'xh' },
    { text: 'Yiddish', val: 'yi' },
    { text: 'Yoruba', val: 'yo' },
    { text: 'Zulu', val: 'zu' }
  ];


/**
 * Callback for rendering the main card.
 * @return {CardService.Card} The card to show the user.
 */
function onHomepage(e) {
  return createSelectionCard(e, DEFAULT_ORIGIN_LAN, DEFAULT_DESTINATION_LAN, DEFAULT_INPUT_TEXT, DEFAULT_OUTPUT_TEXT);
}

/**
 * Main function to generate the main card.
 * @param {String} originLanguage Language of the original text.
 * @param {String} destinationLanguage Language of the translation.
 * @param {String} inputText The text to be translated.
 * @param {String} outputText The text translated.
 * @return {CardService.Card} The card to show to the user.
 */
function createSelectionCard(e, originLanguage, destinationLanguage, inputText, outputText) {
  var hostApp = e['hostApp'];
  var builder = CardService.newCardBuilder();

  // "From" language selection & text input section
  var fromSection = CardService.newCardSection()
    .addWidget(generateLanguagesDropdown('origin', 'From: ', originLanguage))
    .addWidget(CardService.newTextInput()
      .setFieldName('input')
      .setValue(inputText)
      .setTitle('Enter text...')
      .setMultiline(true));

  if (hostApp === 'docs') {
    fromSection.addWidget(CardService.newButtonSet()
      .addButton(CardService.newTextButton()
        .setText('Get Selection')
        .setOnClickAction(CardService.newAction().setFunctionName('getDocsSelection'))
        .setDisabled(false)))
  } else if (hostApp === 'sheets') {
    fromSection.addWidget(CardService.newButtonSet()
      .addButton(CardService.newTextButton()
        .setText('Get Selection')
        .setOnClickAction(CardService.newAction().setFunctionName('getSheetsSelection'))
        .setDisabled(false)))
  } else if (hostApp === 'slides') {
    fromSection.addWidget(CardService.newButtonSet()
      .addButton(CardService.newTextButton()
        .setText('Get Selection')
        .setOnClickAction(CardService.newAction().setFunctionName('getSlidesSelection'))
        .setDisabled(false)))
  }


  builder.addSection(fromSection);

  // "Translation" language selection & text input section
  builder.addSection(CardService.newCardSection()
    .addWidget(generateLanguagesDropdown('destination', 'To: ', destinationLanguage))
    .addWidget(CardService.newTextInput()
      .setFieldName('output')
      .setValue(outputText)
      .setTitle('Translation...')
      .setMultiline(true)));

  //Buttons section
  builder.addSection(CardService.newCardSection()
    .addWidget(CardService.newButtonSet()
      .addButton(CardService.newTextButton()
        .setText('Translate')
        .setTextButtonStyle(CardService.TextButtonStyle.FILLED)
        .setOnClickAction(CardService.newAction().setFunctionName('translateText'))
        .setDisabled(false))
      .addButton(CardService.newTextButton()
        .setText('Clear')
        .setOnClickAction(CardService.newAction().setFunctionName('clearText'))
        .setDisabled(false))));

  return builder.build();

}

/**
 * Helper function to generate the drop down language menu. It checks what language the user had selected.
 * @param {String} fieldName
 * @param {String} fieldTitle
 * @param {String} previousSelected The language the user previously had selected.
 * @return {CardService.SelectionInput} The card to show to the user.
 */
function generateLanguagesDropdown(fieldName, fieldTitle, previousSelected) {
  var selectionInput = CardService.newSelectionInput().setTitle(fieldTitle)
    .setFieldName(fieldName)
    .setType(CardService.SelectionInputType.DROPDOWN);

  LANGUAGE_MAP.forEach((language, index, array) => {
    selectionInput.addItem(language.text, language.val, language.val == previousSelected);
  })

  return selectionInput;
}

/**
 * Helper function to translate the text. If the originLanguage is an empty string, the API detects the language
 * @return {CardService.Card} The card to show to the user.
 */
function translateText(e) {
  var originLanguage = e.formInput.origin;
  var destinationLanguage = e.formInput.destination;
  var inputText = e.formInput.input;

  if (originLanguage !== destinationLanguage && inputText !== undefined) {
    var translation = LanguageApp.translate(e.formInput.input, e.formInput.origin, e.formInput.destination);
    return createSelectionCard(e, originLanguage, destinationLanguage, inputText, translation);
  }
}

/**
 * Helper function to clean the text.
 * @return {CardService.Card} The card to show to the user.
 */
function clearText(e) {
  var originLanguage = e.formInput.origin;
  var destinationLanguage = e.formInput.destination;
  return createSelectionCard(e, originLanguage, destinationLanguage, DEFAULT_INPUT_TEXT, DEFAULT_OUTPUT_TEXT);
}

/**
 * Helper function to get the text selected.
 * @return {CardService.Card} The selected text.
 */
function getDocsSelection(e) {
  var text = '';
  var selection = DocumentApp.getActiveDocument().getSelection();
  Logger.log(selection)
  if (selection) {
    var elements = selection.getRangeElements();
    for (var i = 0; i < elements.length; i++) {
      Logger.log(elements[i]);
      var element = elements[i];
      // Only modify elements that can be edited as text; skip images and other non-text elements.
      if (element.getElement().asText() && element.getElement().asText().getText() !== '') {
        text += element.getElement().asText().getText() + '\n';
      }
    }
  }

  if (text !== '') {
    var originLanguage = e.formInput.origin;
    var destinationLanguage = e.formInput.destination;
    var translation = LanguageApp.translate(text, e.formInput.origin, e.formInput.destination);
    return createSelectionCard(e, originLanguage, destinationLanguage, text, translation);
  }
}

/**
 * Helper function to get the text of the selected cells.
 * @return {CardService.Card} The selected text.
 */
function getSheetsSelection(e) {
  var text = '';
  var ranges = SpreadsheetApp.getActive().getSelection().getActiveRangeList().getRanges();
  for (var i = 0; i < ranges.length; i++) {
    const range = ranges[i];
    const numRows = range.getNumRows();
    const numCols = range.getNumColumns();
    for (let i = 1; i <= numCols; i++) {
      for (let j = 1; j <= numRows; j++) {
        const cell = range.getCell(j, i);
        if (cell.getValue()) {
          text += cell.getValue() + '\n';
        }
      }
    }
  }
  if (text !== '') {
    var originLanguage = e.formInput.origin;
    var destinationLanguage = e.formInput.destination;
    var translation = LanguageApp.translate(text, e.formInput.origin, e.formInput.destination);
    return createSelectionCard(e, originLanguage, destinationLanguage, text, translation);
  }
}

/**
 * Helper function to get the selected text of the active slide.
 * @return {CardService.Card} The selected text.
 */
function getSlidesSelection(e) {
  var text = '';
  var selection = SlidesApp.getActivePresentation().getSelection();
  var selectionType = selection.getSelectionType();
  if (selectionType === SlidesApp.SelectionType.TEXT) {
    var textRange = selection.getTextRange();
    if (textRange.asString() !== '') {
      text += textRange.asString() + '\n';
    }
  }
  if (text !== '') {
    var originLanguage = e.formInput.origin;
    var destinationLanguage = e.formInput.destination;
    var translation = LanguageApp.translate(text, e.formInput.origin, e.formInput.destination);
    return createSelectionCard(e, originLanguage, destinationLanguage, text, translation);
  }
}
```

### appsscript.json

```
{
  "timeZone": "America/New_York",
  "dependencies": {},
  "exceptionLogging": "STACKDRIVER",
  "oauthScopes": [
    "https://www.googleapis.com/auth/documents.currentonly",
    "https://www.googleapis.com/auth/spreadsheets.currentonly",
    "https://www.googleapis.com/auth/presentations.currentonly"
  ],
  "runtimeVersion": "V8",
  "addOns": {
    "common": {
      "name": "Translate",
      "logoUrl": "https://www.gstatic.com/images/branding/product/1x/translate_24dp.png",
      "layoutProperties": {
        "primaryColor": "#2772ed"
      },
      "homepageTrigger": {
        "runFunction": "onHomepage"
      }
    },
    "docs" : {},
    "slides" : {},
    "sheets" : {}
  }
}
```

<br />

## Contributors

This sample is maintained by Google with the help of Google Developer Experts.

## Next steps

- [Extend Google Workspace with add-ons](https://developers.google.com/workspace/add-ons/overview)
- [Build Google Workspace add-ons](https://developers.google.com/workspace/add-ons/how-tos/building-workspace-addons)
- [Publish an app](https://developers.google.com/workspace/marketplace/how-to-publish)