Prompt to confirm number before SMS or call.

core-util/src/main/java/org/signal/core/util/TranslationDetection.java

@@ -0,0 +1,64 @@
+package org.signal.core.util;
+
+import android.content.Context;
+import android.content.res.Configuration;
+import android.content.res.Resources;
+import android.os.Build;
+
+import androidx.annotation.NonNull;
+import androidx.annotation.StringRes;
+
+import java.util.Locale;
+
+/**
+ * Allows you to detect if a string resource is readable by the user according to their language settings.
+ */
+public final class TranslationDetection {
+  private final Resources     resourcesLocal;
+  private final Resources     resourcesEn;
+  private final Configuration configurationLocal;
+
+  /**
+   * @param context Do not pass Application context, as this may not represent the users selected in-app locale.
+   */
+  public TranslationDetection(@NonNull Context context) {
+    this.resourcesLocal     = context.getResources();
+    this.configurationLocal = resourcesLocal.getConfiguration();
+
+    Configuration configurationEn = new Configuration(configurationLocal);
+    configurationEn.setLocale(Locale.ENGLISH);
+
+    this.resourcesEn = context.createConfigurationContext(configurationEn).getResources();
+  }
+
+  /**
+   * Returns true if any of these are true:
+   * - The current locale is English.
+   * - In a multi-locale capable device, the device supports any English locale in any position.
+   * - The text for the current locale does not Equal the English.
+   */
+  public boolean textExistsInUsersLanguage(@StringRes int resId) {
+    if (configSupportsEnglish()) {
+      return true;
+    }
+
+    String stringEn    = resourcesEn.getString(resId);
+    String stringLocal = resourcesLocal.getString(resId);
+
+    return !stringEn.equals(stringLocal);
+  }
+
+  protected boolean configSupportsEnglish() {
+    if (configurationLocal.locale.getLanguage().equals("en")) {
+      return true;
+    }
+
+    if (Build.VERSION.SDK_INT >= 24) {
+      Locale firstMatch = configurationLocal.getLocales().getFirstMatch(new String[]{"en"});
+
+      return firstMatch != null && firstMatch.getLanguage().equals("en");
+    }
+
+    return false;
+  }
+}