blackberry - Delete Persistent Store data when App is uninstalled/deleted -

i have blackberry application starts (app load) registration screen when app first installed. later, app load home screen. registration screen appears on first load. achieving storing boolean value in persistentstore. if value exists, registration screen not appear.

persistentstorehelper.persistenthashtable.put("flagged",boolean.true); persistentstorehelper.persistentobject.commit(); uiapplication.getuiapplication().pushscreen(new myscreen()); 

i aware of fact in order delete persistent store on deleting/uninstalling app, have make hashtable subclass of own , therefore have declared hashtable in separate class:

public class persistentstorehelper extends hashtable implements persistable{      public static persistentobject persistentobject;     public static final long key = 0x9df9f961bc6d6dal;     public static hashtable persistenthashtable;  } 

however has not helped , boolean value of flag not cleared persistentstore. please advice.

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edit: when change above persistentstorehelper class

public static persistentobject persistentobject =     persistentstore.getpersistentobject(key); 

and remove

persistentstorehelper.persistentobject =      persistentstore.getpersistentobject(persistentstorehelper.key); 

from class b boolean value being saved, observe boolean value removed every time app closed. should not happen , value should removed in case app deleted/uninstalled. pointers?

the way works blackberry os looks @ objects storing in persistentstore. if recognizes objects can used app, delete them when uninstall app. however, if classes of stored objects classes used other apps, data not deleted.

you have declared helper class this:

public class persistentstorehelper extends hashtable implements persistable{ 

but helper class not being stored. helper class helper, stores other things you. in case, storing this:

public static hashtable persistenthashtable; 

but, object of type java.util.hashtable, class used many apps. so, won't deleted when uninstall app. should this:

public class persistentstorehelper implements persistable {  // inner class = persistable      public static persistentobject persistentobject;     public static final long key = 0x9df9f961bc6d6dal;     /**        * persistenthashtable instance of class       * exists in app        */     public static myappshashtable persistenthashtable;      private class myappshashtable extends hashtable implements persistable {         // don't need else ... declaration all!     } } 

i can't see here, i'm assuming somewhere have code:

persistentobject = persistentstore.getpersistentobject(key); 

and when want save data store, you're doing this;

persistenthashtable.put("somekey", somenewdata); persistentobject.setcontents(persistenthashtable); persistentobject.commit(); 

just adding data persistenthashtable doesn't save (permanently). hopefully, had part somewhere.

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note: if make these changes, don't expect line of code work, next time run app:

persistenthashtable = (myappshashtable)persistentobject.getcontents(); 

because last version of code did not use myappshashtable class, loaded data won't of type. 1 reason it's important right first time. in general, wind saving data in persistentstore that's contained in 1 top level hashtable subclass, implements persistable. may later change goes in it, won't ever change signature of top-level storage object. hopefully, haven't released app already.

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update: in response comment/question below:

if (persistentstorehelper.persistentobject.getcontents() == null) {        persistentstorehelper.persistenthashtable = new myappshashtable();         persistentstorehelper.persistentobject.setcontents(persistentstorehelper.persist‌enthashtable);  } else {      persistentstorehelper.persistenthashtable =          (myappshashtable)persistentstorehelper.persistentobject.getcontents();  }