README.md

i18n-translate-qt-ts

Automatically translates Qt Linguist TS file to different languages via Google Translate API.

Note: Use requires a commercial Google API key.

Usage:

i18n-translate-qt-ts <googleTranslateApiKey> <workingFolder> <inputLanguage>

• <googleTranslateApiKey> - Your commercial Google Translate API key
• <workingFolder> - Folder containing your Qt *.ts files
• <sourceLanguage> - Source strings language abbreviation, for example, 'en'

Example:

i18n-translate-qt-ts myLongSecretApiKey app/i18n en

Qt

A C++ based cross-platform SDK supporting desktops, embedded, Android, and iOS.

• https://www.qt.io/

Qt Linguist

• http://doc.qt.io/qt-5/qtlinguist-index.html

Qt Linguist TS File Format

• http://doc.qt.io/qt-5/linguist-ts-file-format.html

Example

Before Translation

File: myproject_es.ts

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE TS>
<TS version="2.0" language="es">
  <context>
      <name>QPushButton</name>
      <message>
          <source>Hello</source>
          <translation type="unfinished"></translation>
      </message>
  </context>
</TS>

After Translation

File: myproject_es.ts

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE TS>
<TS version="2.0" language="es">
  <context>
      <name>QPushButton</name>
      <message>
          <source>Hello</source>
          <translation type="finished">Hola</translation>          
      </message>
  </context>
</TS>

Development - Getting Started

git clone https://github.com/esutton/i18n-translate-qt-ts.git i18n-translate-qt-ts/source
cd 18n-translate-qt-ts/source
yarn
npm install -g

# Check global installed packages
npm list -g --depth=0

# Use environment variable to store your API key
export API_KEY=AIzy0Vj...

# Generate German (de.ts) and Spanish (es.ts) translations 
# from English (*_en.ts) file 
# found in folder test/i18n..

node index.js ${API_KEY} test/simple/unfinished en

Working with Qt Translation

See: qt-translation-example

• For all displayed and printed string literals in you app use tr().
• The Qt lupdate will serach your project for all tr() and create *.ts files.
  • For example:
    • tr("Hello %1 !").arg(nameFirst)
  • http://doc.qt.io/qt-5/i18n-source-translation.html

1. Add languages you wish to support to your Qt project file (*.pro) and run qmake again

TRANSLATIONS += \
    languages/TranslationExample_en.ts  \
    languages/TranslationExample_de.ts

2. Use Qt lupdate to auto-generate your initial ts files.

   • From Qt Creator menu select:
     • Tools > External > Linguist > Update Translations (lupdate)

3. For each <message> found in each TSL file translate the <source> text and paste into <translation>

   • Manually change translation/@type attribute from "unfinished" to "finished".
   • Or delete translation/@type attribute after translation.
   • When you run lupdate again, it will removed all translation/@type=finished attributes
     • Missing type attribute is same as "finished"
     • Y
   • For small one-by-word projects, use free web browser Google Translate.
     • https://translate.google.com/?
   • I made this node.js script that requires a commercial Google Translate API key:
     • https://github.com/esutton/i18n-translate-qt-ts

4. Use Qt lrelease to generate compressed *.qm files from translated *.ts files

   • From Qt Creator menu select:
     • Tools > External > Linguist > Release Translations (lrelease)

5. Copy *.qm files to the embedded resource folder ./res/translation

   • ToDo: Add code to *.pro file to copy *.qm to ./res/translation

Automated Translation Using Google Translate

i18n-translate-qt-ts

I created this i18n-translate-qt-ts as a node.js command line utility.

I was inspired by another github project i18n-translate-json used to auto-translate a react native app

• i18n-translate-json

Since i18n-translate-json was so helpful, I felt obligated to share i18n-translate-qt-ts.

• Ulterior motive: I was hoping someone in the community might help improve on it.

Use requires a commercial Google Translate API key:

• https://github.com/esutton/i18n-translate-qt-ts

To add translations to all ./languages/*.ts files in the qt-translation-example project:

# Use environment variable to store your API key
export API_KEY=AIzy0Vj...AIzy0VjQ
node index.js ${API_KEY} languages en

• Seems to work best if you process in small batches of one or two *.ts files.
  • Too many async queries active?
• If errors occur, you may need to run multiple times until all strings have translations.
  • Perhaps throttling the API calls might help this.
• If needed, send auto-translations to a native speaker for improvements.
  • i18n-translate-qt-ts will not update a manual translation unless translation/@type=unfinished or source string is non-empty and <translation> is empty.