LayerListDialog.java

package edu.purdue.app.map;

import java.util.ArrayList;
import java.util.List;

import android.app.AlertDialog;
import android.app.Dialog;
import android.app.DialogFragment;
import android.content.Context;
import android.content.DialogInterface;
import android.os.Bundle;

public class LayerListDialog extends DialogFragment {
	
	/** Listener that is called when the dialog box is confirmed */
	MapLayersUpdateListener listener;
	Context c;
	
	/** MapData which is used to populate the list of layers */
	MapData mpd;
	
	/** onLayersUpdate is called when the user updates their selection of layers */
	public interface MapLayersUpdateListener {
		void onLayersUpdate(List<String> enabled);
	}
	
	@Override
	public Dialog onCreateDialog(Bundle savedInstanceState) {
		
		// Create the mapdata object
		mpd = new MapData(c);
		
		// Build the alert dialog
		AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
		final List<String> enabledLayers = new ArrayList<String>();
		
		// Convert string list to string array
		String[] layersList = new String[mpd.getLayersList().size()];
		for (int i = 0; i < mpd.getLayersList().size(); i++) {
			layersList[i] = mpd.getLayersList().get(i);
		}
		
		builder.setTitle("Layers");
		builder.setMultiChoiceItems(layersList, null, new DialogInterface.OnMultiChoiceClickListener() {
			
			@Override
			public void onClick(DialogInterface dialog, int which, boolean isChecked) {
				if (isChecked) {
					enabledLayers.add(mpd.getLayersList().get(which));
				} else {
					enabledLayers.remove(mpd.getLayersList().get(which));
				}
			}
			
		});
		
		builder.setPositiveButton("Confirm", new DialogInterface.OnClickListener() {
			@Override
			public void onClick(DialogInterface dialog, int which) {
				listener.onLayersUpdate(enabledLayers);
			}
		});
		
		return builder.create();
		
	}
	
	public void setOnUpdateListener(MapLayersUpdateListener listener, Context c) {
		this.listener = listener;
		this.c = c;
	}

}