Question

I am working to create a db file in my application. Now I want to create the .db file on application installation just one time.
When I open the app, it just check for the existence of the file.

How can we check for a .db file in sdcard and if it exists before installation than to delete the file.

Answer 1

You can check if file exists or not using following code

 FileConnection fileConnection = (FileConnection)Connector.open("file:///SDCard/foldername/" + "databasename.db");

    boolean result=fileConnection.exists(); 

  if(result)
  {
     //database available
  }else{
       //database not available
  }

and next you want to check this when application first time instalation using

 CodeModuleListener listner=new CodeModuleListener() {

            public void modulesDeleted(String[] moduleNames) {
                // TODO Auto-generated method stub

            }

            public void modulesAdded(int[] handles) {
                // TODO Auto-generated method stub
                //here you can check if database available or not if available then delete 
                try{
                    URI myURI = URI.create("file:///SDCard/foldername/" + "database_name.db"); 
                    DatabaseFactory.delete(myURI);  
                }catch (Exception e) {
                    // TODO: handle exception
                }

            }

            public void moduleDeletionsPending(String[] moduleNames) {
                // TODO Auto-generated method stub

            }
        };
        CodeModuleManager.addListener(this.getApplication(), listner);