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⇱ How can developers can automatically restart a HarmonyOS app after clearing all app data? - DEV Community

Read the original article：How can developers can automatically restart a HarmonyOS app after clearing all app data?

Question

How can developers automatically restart a HarmonyOS app after clearing all app data, given that ApplicationContext.clearUpApplicationData exits the app without triggering a callback?

Short Answer

ApplicationContext.clearUpApplicationData clears all app data and directly exits the app, so it does not provide a callback for when data is successfully cleared. To achieve the requirement, you need to:

  1. Use appRecovery API to configure app restart behavior.
  2. Manually implement cache/data cleanup with the fs module if you need a completion timing.
  3. Trigger appRecovery.restartApp() only after your cleanup logic completes, instead of relying on clearUpApplicationData.

Solution Code Examples:

1.Configure App Recovery in AbilityStage

 // AbilityStage
 import appRecovery from '@ohos.app.ability.appRecovery';
 import AbilityStage from '@ohos.app.ability.AbilityStage';

 export default class MyAbilityStage extends AbilityStage {
 onCreate() {
 appRecovery.enableAppRecovery(
 appRecovery.RestartFlag.ALWAYS_RESTART,
 appRecovery.SaveOccasionFlag.SAVE_WHEN_ERROR,
 appRecovery.SaveModeFlag.SAVE_WITH_FILE
 );

 let want = {
 bundleName: 'com.example.test',
 abilityName: 'EntryAbility'
 }
 appRecovery.setRestartWant(want)
 }
 }

2.Configure Ability as startup

 "module": {
 "name": "entry",
 "srcEntry": "./ets/AbilityStage/AbilityStage.ets",
 ...
 },
 "abilities": [
 {
 "name": "EntryAbility",
 "recoverable": true,
 ...
 }
 ]

3.Restart App on Button Click

 Button('Restart App')
 .onClick(() => {
 appRecovery.restartApp();
 })

4.Manually Clear Cache with fs (timing control)

 import { storageStatistics } from '@kit.CoreFileKit';
 import fs from '@ohos.file.fs';
 import { Context } from '@kit.AbilityKit';
 import { BusinessError } from '@ohos.base';

 @Entry
 @Component
 struct Clearcache {
 build() {
 Button('Clear cache')
 .onClick(() => {
 const context: Context = getContext(this);
 let cacheDir = context.cacheDir;

 fs.listFile(cacheDir).then((filenames) => {
 for (let i = 0; i < filenames.length; i++) {
 let dirPath = cacheDir + filenames[i];
 try {
 let isDirectory = fs.statSync(dirPath).isDirectory();
 if (isDirectory) {
 fs.rmdirSync(dirPath);
 } else {
 fs.unlink(dirPath).then(() => {
 console.info('remove file succeed');
 }).catch((err: BusinessError) => {
 console.error("remove file failed: " + err.message);
 });
 }
 } catch (e) {
 console.log(e);
 }
 }
 // βœ… Restart app after cleanup completes
 appRecovery.restartApp();
 })
 })
 }
 }

Applicable Scenarios

  • When you want the application to restart automatically after clearing app cache or local data.
  • When you need precise control of the timing after data deletion (e.g., clear user sessions, local storage, or cache).
  • When clearUpApplicationData exits the app immediately and you require a custom solution that ensures restart.
  • Suitable for HarmonyOS applications that must ensure recovery/restart flow after cleanup.

Reference Link

https://developer.huawei.com/consumer/en/doc/harmonyos-references-V5/js-apis-inner-application-applicationcontext-V5

Written by Mehmet Algul