OrderFragment.java

package hk.hku.cs.srli.factfinder;

import android.app.AlertDialog;
import android.app.Fragment;
import android.content.Context;
import android.content.DialogInterface;
import android.database.DataSetObserver;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

import com.example.android.swipedismiss.SwipeDismissListViewTouchListener;

import java.util.List;

import hk.hku.cs.srli.factfinder.DataSet.DataItem;

public class OrderFragment extends Fragment {

    private ListView mListView;
    private Order mOrder;
    private OrderAdapter mAdapter;
    
    // flag indicating an item is being removed
    private boolean removing = false;
    
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.fragment_order, container, false);
        mListView = (ListView) rootView.findViewById(R.id.orderListView);
        return rootView;
    }
    
    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);
        
        mOrder = FFApp.getOrder(getActivity());
        mAdapter = new OrderAdapter(getActivity(), mOrder.getItemList()); 
        mOrder.setAdapter(mAdapter);
        mListView.setAdapter(mAdapter);
        mListView.setEmptyView(getView().findViewById(R.id.textEmpty));
        
        // helper to remove item by swipe
        SwipeDismissListViewTouchListener touchListener =
                new SwipeDismissListViewTouchListener(
                        mListView,
                        new SwipeDismissListViewTouchListener.DismissCallbacks() {
                            
                            @Override
                            public void onDismiss(ListView listView, int[] reverseSortedPositions) {
                                for (int position : reverseSortedPositions) {
                                    mAdapter.remove(mAdapter.getItem(position));
                                }
                                removing = true;
                                mAdapter.notifyDataSetChanged();
                            }
                            
                            @Override
                            public boolean canDismiss(int position) {
                                return true;
                            }
                        });
        mListView.setOnTouchListener(touchListener);
        mListView.setOnScrollListener(touchListener.makeScrollListener());
        
        mAdapter.registerDataSetObserver(new DataSetObserver() {
            
            @Override
            public void onChanged() {
                if (!removing) {
                    // when new item is added to order (instead of removing)
                    mListView.post(new Runnable() {
                        @Override
                        public void run() {
                            // scroll list to bottom
                            mListView.smoothScrollToPosition(mAdapter.getCount() - 1);
                        }
                    });
                    removing = false;
                }
                refreshOrder();
            }
        });
        
        Button submitButton = (Button) getView().findViewById(R.id.buttonOrder);
        submitButton.setOnClickListener(new View.OnClickListener() {
            
            @Override
            public void onClick(View v) {
                // show confirmation dialog 
                new AlertDialog.Builder(getActivity())
                    .setTitle("Confirm order")
                    .setMessage("You have ordered " + mAdapter.getCount() + " items. " + 
                            "Total: " + DataSet.formatMoney(mOrder.getSum()) + ".")
                    .setPositiveButton("Confirm", new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialog, int which) {
                            mOrder.submit();
                            // inform the user by toast
                            Toast.makeText(getActivity(), "Order submitted.", Toast.LENGTH_LONG).show();
                        }
                    }).setNeutralButton("Clear", new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialog, int which) {
                            mOrder.clear();
                            dialog.dismiss();
                        }
                    }).setNegativeButton(android.R.string.cancel, new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialog, int which) {
                            dialog.dismiss();
                        }
                    }).show();
            }
        });
        refreshOrder();
    }

    private void refreshOrder() {
        TextView sum = (TextView) getView().findViewById(R.id.textOrderSum);
        if (mOrder.getSum() > 0) {
            sum.setText("Total: " + DataSet.formatMoney(mOrder.getSum()));
        } else {
            // show nothing when order total is zero
            sum.setText("");
        }
        
        Button submitButton = (Button) getView().findViewById(R.id.buttonOrder);
        submitButton.setEnabled(mAdapter.getCount() > 0);
    }

    public static class OrderAdapter extends ArrayAdapter<DataItem> {

        public OrderAdapter(Context context, List<DataItem> objects) {
            super(context, R.layout.order_item, R.id.textViewLeft, objects);
        }
        
        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            View view = super.getView(position, convertView, parent);
            DataItem item = getItem(position);
            
            // name
            TextView text1 = (TextView) view.findViewById(R.id.textViewLeft);
            if (item.name != null && item.name.length() > 0)
                text1.setText(item.name);
            else
                text1.setText(item.title);
            
            // price
            TextView text2 = (TextView) view.findViewById(R.id.textViewRight);
            text2.setText(DataSet.formatMoney(item.price));
            
            // category name
            TextView text3 = (TextView) view.findViewById(R.id.textViewSmall);
            text3.setText(FFApp.getData(getContext()).getCategoryFromItem(item).getName());
            return view;
        }
    }
}