User Preference Setting

Use Cases

In addition to system locales and application preferred languages, the system supports setting of user preferences. Currently, the system supports two user preferences: whether to use local digits and whether to use the 12/24-hour format. User preference settings are saved to system locales and application preferred languages as part of the internationalization feature.

How to Develop

User preference setting is implemented by using setUsingLocalDigit and set24HourClock. The development procedure is as follows:

1. Import the intl module.

   import Intl from '@ohos.intl';
   import I18n from '@ohos.i18n';
   import { BusinessError } from '@ohos.base';
   

2. Obtain the preferred language of an application.

   try {
     // Obtain the preferred language of the application. Assume that the current preferred language is ar.
     let appPreferredLanguage: string = I18n.System.getAppPreferredLanguage();
   } catch(error) {
     let err: BusinessError = error as BusinessError;
     console.error(`call System.getAppPreferredLanguage failed, error code: ${err.code}, message: ${err.message}.`);
   }
   

3. Enable display of local digits on the application page.

   try {  
     I18n.System.setUsingLocalDigit(true); // Enable the local digit switch.
   } catch(error) {
     let err: BusinessError = error as BusinessError;
     console.error(`call System.setUsingLocalDigit failed, error code: ${err.code}, message: ${err.message}.`);
   }
   let date = new Date(2023, 9, 25);
   let dateTimeFmt = new Intl.DateTimeFormat(appPreferredLanguage);
   let result = dateTimeFmt.format(date); // result = "٢٠٢٣/١٠/٢٥" (local Arabic digits)
   

4. Set the 24-hour clock format.

   try {  
     I18n.System.set24HourClock(true); // true means to enable the 24-hour clock, and false means to enable the 12-hour clock.
   } catch(error) {
     let err: BusinessError = error as BusinessError;
     console.error(`call System.set24HourClock failed, error code: ${err.code}, message: ${err.message}.`);
   }
   let date = new Date(2023, 9, 25, 16, 48, 0);
   let dateTimeFmt = new Intl.DateTimeFormat(appPreferredLanguage, { timeStyle: "medium" });
   let result = dateTimeFmt.format(date); // result = "16:48:00"