android.app.backup.BackupManager#dataChanged ( )源码实例Demo

public static boolean saveDatabase(Context context, ArrayList<Entry> entries, SecretKey encryptionKey) {
    if (encryptionKey == null) {
        Toast.makeText(context, R.string.toast_encryption_key_empty, Toast.LENGTH_LONG).show();
        return false;
    }

    String jsonString = entriesToString(entries);

    try {
        synchronized (DatabaseHelper.DatabaseFileLock) {
            byte[] data = EncryptionHelper.encrypt(encryptionKey, jsonString.getBytes());

            FileHelper.writeBytesToFile(new File(context.getFilesDir() + "/" + Constants.FILENAME_DATABASE), data);
        }
    } catch (Exception error) {
        error.printStackTrace();
        return false;
    }

    BackupManager backupManager = new BackupManager(context);
    backupManager.dataChanged();

    return true;
}
 

public static String getUserID(Context context) {
    if (uniqueID == null) {
        SharedPreferences sharedPrefs = context.getSharedPreferences(SimpleBackupAgent.PREFS, Context.MODE_PRIVATE);
        uniqueID = sharedPrefs.getString(PREF_UNIQUE_ID, null);
        if (uniqueID == null) {
            uniqueID = UUID.randomUUID().toString();
            SharedPreferences.Editor editor = sharedPrefs.edit();
            editor.putString(PREF_UNIQUE_ID, uniqueID);
            editor.commit();

            //backup the changes
            BackupManager mBackupManager = new BackupManager(context);
            mBackupManager.dataChanged();
        }
    }

    return uniqueID;
}
 

private void setStringUnchecked(String key, int userId, String value) {
    Preconditions.checkArgument(userId != USER_FRP, "cannot store lock settings for FRP user");

    mStorage.writeKeyValue(key, value, userId);
    if (ArrayUtils.contains(SETTINGS_TO_BACKUP, key)) {
        BackupManager.dataChanged("com.android.providers.settings");
    }
}
 

public void onSharedPreferenceChanged(SharedPreferences prefs, String key) {
    BackupManager backupManager = new BackupManager(this);
    backupManager.dataChanged();

    if (key.equals(getString(R.string.settings_key_theme)) ||
            key.equals(getString(R.string.settings_key_locale)) ||
            key.equals(getString(R.string.settings_key_special_features)) ||
            key.equals(getString(R.string.settings_key_backup_location))) {
        recreate();
    } else if(key.equals(getString(R.string.settings_key_encryption))) {
        if (settings.getEncryption() != EncryptionType.PASSWORD) {
            if (settings.getAndroidBackupServiceEnabled()) {
                UIHelper.showGenericDialog(this,
                    R.string.settings_dialog_title_android_sync,
                    R.string.settings_dialog_msg_android_sync_disabled_encryption
                );
            }

            settings.setAndroidBackupServiceEnabled(false);
            if (fragment.useAndroidSync != null) {
                fragment.useAndroidSync.setEnabled(false);
                fragment.useAndroidSync.setChecked(false);
            }
        } else {
            if (fragment.useAndroidSync != null)
                fragment.useAndroidSync.setEnabled(true);
        }
    }

    fragment.updateAutoBackup();
}
 

/** Schedule backups each time the preferences are modified. */
public static SharedPreferences.OnSharedPreferenceChangeListener
    registerOnSharedPreferencesChangeListener(Context applicationContext) {
  SharedPreferences.OnSharedPreferenceChangeListener listener =
      (sharedPreferences, s) ->
          BackupManager.dataChanged("com.google.android.apps.forscience.whistlepunk");
  PreferenceManager.getDefaultSharedPreferences(applicationContext)
      .registerOnSharedPreferenceChangeListener(listener);
  return listener;
}
 

private ChromeBackupWatcher() {
    Context context = ContextUtils.getApplicationContext();
    if (context == null) return;

    mBackupManager = new BackupManager(context);
    // Watch the Java preferences that are backed up.
    SharedPreferences sharedPrefs = ContextUtils.getAppSharedPreferences();
    // If we have never done a backup do one immediately.
    if (!sharedPrefs.getBoolean(FIRST_BACKUP_DONE, false)) {
        mBackupManager.dataChanged();
        sharedPrefs.edit().putBoolean(FIRST_BACKUP_DONE, true).apply();
    }
    sharedPrefs.registerOnSharedPreferenceChangeListener(
            new SharedPreferences.OnSharedPreferenceChangeListener() {

                @Override
                public void onSharedPreferenceChanged(
                        SharedPreferences sharedPreferences, String key) {
                    // Update the backup if the user id or any of the backed up Android
                    // preferences change.
                    if (key.equals(ChromeSigninController.SIGNED_IN_ACCOUNT_KEY)) {
                        onBackupPrefsChanged();
                        return;
                    }
                    for (String pref : ChromeBackupAgent.BACKUP_ANDROID_BOOL_PREFS) {
                        if (key.equals(pref)) {
                            onBackupPrefsChanged();
                            return;
                        }
                    }
                }

            });
}
 

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    identityProvider = DeviceIdentityProvider.getInstance(this);

    // force backup for new device immediately
    if (identityProvider.isNewDevice()) {
        BackupManager backupManager = new BackupManager(this);
        backupManager.dataChanged();
    }
    
    initView();
}
 

@Override
protected void onStop() {
    // allow backup authorized devices only
    if (identityProvider.isAuthorizedDevice()) {
        BackupManager backupManager = new BackupManager(this);
        backupManager.dataChanged();
    }

    super.onStop();
}
 

private ChromeBackupWatcher() {
    Context context = ContextUtils.getApplicationContext();
    if (context == null) return;

    mBackupManager = new BackupManager(context);
    // Watch the Java preferences that are backed up.
    SharedPreferences sharedPrefs = ContextUtils.getAppSharedPreferences();
    // If we have never done a backup do one immediately.
    if (!sharedPrefs.getBoolean(FIRST_BACKUP_DONE, false)) {
        mBackupManager.dataChanged();
        sharedPrefs.edit().putBoolean(FIRST_BACKUP_DONE, true).apply();
    }
    sharedPrefs.registerOnSharedPreferenceChangeListener(
            new SharedPreferences.OnSharedPreferenceChangeListener() {

                @Override
                public void onSharedPreferenceChanged(
                        SharedPreferences sharedPreferences, String key) {
                    // Update the backup if the user id or any of the backed up Android
                    // preferences change.
                    if (key.equals(ChromeSigninController.SIGNED_IN_ACCOUNT_KEY)) {
                        onBackupPrefsChanged();
                        return;
                    }
                    for (String pref : ChromeBackupAgent.BACKUP_ANDROID_BOOL_PREFS) {
                        if (key.equals(pref)) {
                            onBackupPrefsChanged();
                            return;
                        }
                    }
                }

            });
}
 

@Override
public void dataChanged() {
    BackupManager bmgr = new BackupManager(context);
    bmgr.dataChanged();
}
 

private void scheduleBackup() {
    BackupManager backupManager = new BackupManager(context);
    backupManager.dataChanged();
}
 

public static void requestBackup(Context context) {
    Log.d(MyUtil.PACKAGE_NAME, "requestBackup");
    BackupManager backupManager = new BackupManager(context);
    backupManager.dataChanged();
}
 

/**
 * Let the BackupManager know that account sync settings have changed. This will trigger
 * {@link com.android.server.backup.SystemBackupAgent} to run.
 */
public void queueBackup() {
    BackupManager.dataChanged("android");
}