Added translation support for the iOS.

README.md

@@ -11,7 +11,7 @@ React Native On-Device Machine Learning w/ Google ML Kit
 | [Face Detection](./face-detection)         |   ✅    | ✅  |
 | [Text Recognition](./text-recognition)     |   ✅    | ✅  |
 | [Barcode Scanning](./barcode-scanning)     |   ✅    | ✅  |
-| [Translate Text](./translate-text)         |   ✅    | ❌  |
+| [Translate Text](./translate-text)         |   ✅    | ✅  |
 | Object Detection and Tracking              |   ❌    | ❌  |
 | Digital Ink Recognition                    |   ❌    | ❌  |
 | Smart Replies                              |   ❌    | ❌  |

translate-text/ios/TranslateText.m

@@ -2,15 +2,72 @@
 
 #import "TranslateText.h"
 
+@import MLKitTranslate;
+@import MLKitCommon;
+
 
 @implementation TranslateText
 
 RCT_EXPORT_MODULE()
 
-RCT_EXPORT_METHOD(sampleMethod:(NSString *)stringArgument numberParameter:(nonnull NSNumber *)numberArgument callback:(RCTResponseSenderBlock)callback)
+RCT_EXPORT_METHOD(translate:(NSDictionary *)optionsMap 
+                  resolver:(RCTPromiseResolveBlock)resolve
+                  rejecter:(RCTPromiseRejectBlock)reject)
 {
-    // TODO: Implement some actually useful functionality
-    callback(@[[NSString stringWithFormat: @"numberArgument: %@ stringArgument: %@", numberArgument, stringArgument]]);
+    NSString *text = [optionsMap objectForKey:@"text"];
+
+    if (text == nil) {
+        reject(@"TEXT_TRANSLATE_FAILED", @"Text cannot be null", nil);
+        return;
+    }
+
+    NSString *sourceLanguage = [optionsMap objectForKey:@"sourceLanguage"];
+    NSString *targetLanguage = [optionsMap objectForKey:@"targetLanguage"];
+
+    if (sourceLanguage == nil) {
+        reject(@"TEXT_TRANSLATE_FAILED", @"Source language cannot be null", nil);
+        return;
+    }
+
+    if (targetLanguage == nil) {
+        reject(@"TEXT_TRANSLATE_FAILED", @"Target language cannot be null", nil);
+        return;
+    }
+
+    MLKTranslatorOptions *options = [[MLKTranslatorOptions alloc]
+                                     initWithSourceLanguage:sourceLanguage
+                                     targetLanguage:targetLanguage];
+
+    MLKTranslator *translator = [MLKTranslator
+                                 translatorWithOptions:options];
+
+    bool hasRequireWifi = [optionsMap objectForKey:@"requireWifi"];
+
+    MLKModelDownloadConditions *conditions = [[MLKModelDownloadConditions alloc]
+                                              initWithAllowsCellularAccess:!hasRequireWifi
+                                              allowsBackgroundDownloading:YES];
+
+    [translator
+     downloadModelIfNeededWithConditions:conditions
+     completion:^(NSError *_Nullable error) {
+
+        if (error != nil) {
+            reject(@"TEXT_TRANSLATE_FAILED", @"Error was found", error);
+            return;
+        }
+
+        [translator
+         translateText:text
+         completion:^(NSString *_Nullable translatedText, NSError *_Nullable error)
+         {
+            if (error != nil || translatedText == nil) {
+                reject(@"TEXT_TRANSLATE_FAILED", @"Error was found", error);
+                return;
+            }
+
+            resolve(translatedText);
+        }];
+    }];
 }
 
 @end