AsynkTask is a class that allows for easy use of UI Threading. AsyncTask allows you to preform background tasks in a separate thread with out disrupting the UI thread. In ShotShakr 2.0 I am using AsyncTask to filter the list of shots when a filter is selected. In order to use AsyncTask it must be subclassed and override at least one method (doInBackground(Params… )).

Here is ShotShakr’s UpdateShot Class. Here i am passing in the list of filters and shots.

private class UpdateShots extends AsyncTask<String, Void, ArrayList<Shot>> {

	    	private ArrayList<String> aFilters;
	    	private ArrayList<Shot> aShots;
	   	
	    	public UpdateShots(ArrayList<String> filters, ArrayList<Shot> allShots){
	    	  	aFilters = filters;
	    		aShots = allShots;
	    	}
	   	
	   		
	    	
	    }

doinbackground method does the work of the filtering and after completion postExecute gets fired. Here is where i update the UI Thread with the results.

	@Override
	    	protected void onPostExecute(ArrayList<Shot> result) {
	    		//Update UI Thread
	    		shotpicker.this.filteredShots = result;
	    	}


	    	@Override
	    	protected ArrayList<Shot> doInBackground(String... params) {
	    		ArrayList<Shot> newShots = new ArrayList<Shot>();
	   		
	    			//filter shots
                                // add to new list
	   		
	   		//sends to postexecute
	    		return newShots;
	    	}

Here is how to fire of the AsyncTask

new UpdateShots(filters,allShots).execute();

See a more detailed how to http://developer.android.com/reference/android/os/AsyncTask.html

Cheers