你可以使用 ML Kit 翻譯語言之間的文字。ML Kit 翻譯超過 50 種語言。
立即體驗
- 試試範例應用程式,查看這個 API 的使用範例。
事前準備
- 在專案層級的
build.gradle
檔案中,請務必在buildscript
和allprojects
區段中加入 Google 的 Maven 存放區。 - 將 ML Kit Android 程式庫的依附元件新增至模組的應用程式層級 Gradle 檔案 (通常為
app/build.gradle
):dependencies { // ... implementation 'com.google.mlkit:translate:17.0.2' }
翻譯文字字串
如何將字串翻譯成兩種語言:
建立
Translator
物件,並以原文和譯文語言進行設定:Kotlin
// Create an English-German translator: val options = TranslatorOptions.Builder() .setSourceLanguage(TranslateLanguage.ENGLISH) .setTargetLanguage(TranslateLanguage.GERMAN) .build() val englishGermanTranslator = Translation.getClient(options)
Java
// Create an English-German translator: TranslatorOptions options = new TranslatorOptions.Builder() .setSourceLanguage(TranslateLanguage.ENGLISH) .setTargetLanguage(TranslateLanguage.GERMAN) .build(); final Translator englishGermanTranslator = Translation.getClient(options);
如果您不知道輸入文字的語言,可以使用 Language Identity API 提供語言標記。接著,使用
TranslateLanguage.fromLanguageTag()
將標記轉換為TranslateLanguage
。避免在裝置上同時儲存過多語言模型。
確認所需的翻譯模型已下載到裝置上。 除非您確定模型可供使用,否則不要呼叫
translate()
。Kotlin
var conditions = DownloadConditions.Builder() .requireWifi() .build() englishGermanTranslator.downloadModelIfNeeded(conditions) .addOnSuccessListener { // Model downloaded successfully. Okay to start translating. // (Set a flag, unhide the translation UI, etc.) } .addOnFailureListener { exception -> // Model couldn’t be downloaded or other internal error. // ... }
Java
DownloadConditions conditions = new DownloadConditions.Builder() .requireWifi() .build(); englishGermanTranslator.downloadModelIfNeeded(conditions) .addOnSuccessListener( new OnSuccessListener
() { @Override public void onSuccess(Void v) { // Model downloaded successfully. Okay to start translating. // (Set a flag, unhide the translation UI, etc.) } }) .addOnFailureListener( new OnFailureListener() { @Override public void onFailure(@NonNull Exception e) { // Model couldn’t be downloaded or other internal error. // ... } }); 語言模型大小約為 30 MB,因此除非使用者另有說明,否則請勿使用無端下載語言模型,並且僅使用 Wi-Fi 下載模型。建議您也刪除不需要的模型。請參閱明確管理翻譯模型。
確認模型下載完畢後,將原文語言文字的字串傳送至
translate()
:Kotlin
englishGermanTranslator.translate(text) .addOnSuccessListener { translatedText -> // Translation successful. } .addOnFailureListener { exception -> // Error. // ... }
Java
englishGermanTranslator.translate(text) .addOnSuccessListener( new OnSuccessListener
() { @Override public void onSuccess(@NonNull String translatedText) { // Translation successful. } }) .addOnFailureListener( new OnFailureListener() { @Override public void onFailure(@NonNull Exception e) { // Error. // ... } }); 系統會以您設定的譯文語言將譯文傳遞至成功事件監聽器。
確認不會再使用
Translator
物件時,系統會呼叫close()
方法。如果您是在 Fragment 或 AppCompatActivity 中使用翻譯工具,最簡單的做法是呼叫 Fragment 或 AppCompatActivity 上的 LifecycleOwner.getLifecycle(),並呼叫 Lifecycle.addObserver。例如:
Kotlin
val options = ... val translator = Translation.getClient(options) getLifecycle().addObserver(translator)
Java
TranslatorOptions options = ... Translator translator = Translation.getClient(options); getLifecycle().addObserver(translator); ... use translator ...
請注意,這會假設程式碼位於實作 LifecycleOwner 的類別內 (例如 Fragment 或 AppCompatActivity)。
明確管理翻譯模型
使用上述翻譯 API 時,ML Kit 會視需要自動將特定語言的翻譯模型下載到裝置上。您也可以使用 ML Kit 的翻譯模型管理 API,明確管理要在裝置上使用的翻譯模型。如果您想預先下載模型,或是從裝置中刪除不需要的模型,這項功能就能派上用場。
Kotlin
val modelManager = RemoteModelManager.getInstance() // Get translation models stored on the device. modelManager.getDownloadedModels(TranslateRemoteModel::class.java) .addOnSuccessListener { models -> // ... } .addOnFailureListener { // Error. } // Delete the German model if it's on the device. val germanModel = TranslateRemoteModel.Builder(TranslateLanguage.GERMAN).build() modelManager.deleteDownloadedModel(germanModel) .addOnSuccessListener { // Model deleted. } .addOnFailureListener { // Error. } // Download the French model. val frenchModel = TranslateRemoteModel.Builder(TranslateLanguage.FRENCH).build() val conditions = DownloadConditions.Builder() .requireWifi() .build() modelManager.download(frenchModel, conditions) .addOnSuccessListener { // Model downloaded. } .addOnFailureListener { // Error. }
Java
RemoteModelManager modelManager = RemoteModelManager.getInstance(); // Get translation models stored on the device. modelManager.getDownloadedModels(TranslateRemoteModel.class) .addOnSuccessListener(new OnSuccessListener>() { @Override public void onSuccess(Set models) { // ... } }) .addOnFailureListener(new OnFailureListener() { @Override public void onFailure(@NonNull Exception e) { // Error. } }); // Delete the German model if it's on the device. TranslateRemoteModel germanModel = new TranslateRemoteModel.Builder(TranslateLanguage.GERMAN).build(); modelManager.deleteDownloadedModel(germanModel) .addOnSuccessListener(new OnSuccessListener () { @Override public void onSuccess(Void v) { // Model deleted. } }) .addOnFailureListener(new OnFailureListener() { @Override public void onFailure(@NonNull Exception e) { // Error. } }); // Download the French model. TranslateRemoteModel frenchModel = new TranslateRemoteModel.Builder(TranslateLanguage.FRENCH).build(); DownloadConditions conditions = new DownloadConditions.Builder() .requireWifi() .build(); modelManager.download(frenchModel, conditions) .addOnSuccessListener(new OnSuccessListener () { @Override public void onSuccess(Void v) { // Model downloaded. } }) .addOnFailureListener(new OnFailureListener() { @Override public void onFailure(@NonNull Exception e) { // Error. } });