android - Use array adapter with more views in row in listview

Question

I have stumbled upon a problem I can't quite get my head around, so I was hoping perhaps someone here have had the same problem or knew a good way of solving the problem.

I have created a view containing a ListView. This ListView contains two TextView. The problem is that I don't know where I send the values which are meant to go in the second text view using the ArrayAdapter. Is there a way to send with more information to the ArrayAdapter so that I can feed the "todaysmenu" TextView?

The ArrayAdapter method:

private void createList() {
    ListView lv = (ListView) findViewById(R.id.mylist);
    String[] values = new String[] { "Android", "Linux", "OSX", 
            "WebOS", "Windows7", "Ubuntu", "OS/2"
    };
    ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,R.layout.rowlayout, R.id.restaurantname, values);
    lv.setAdapter(adapter);
}

The row markup:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical" >

    <TextView
        android:id="@+id/restaurantname"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@+id/restaurantname"
        android:textSize="23dp" >

    </TextView>

    <TextView
        android:id="@+id/textView1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@+id/todaysmenu" />

</LinearLayout>

The activity layout:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <ListView
    android:id="@+id/mylist"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">
    </ListView>


</LinearLayout>

At the beginning I got everything to work, but when I added the second textfield problems arouse. In advance, thank you for your help!

Answer 1

To achieve this you have to build a custom adapter and inflate your custom row layout. Using ArrayAdapter won't work because

By default this class expects that the provided resource id references a single TextView. If you want to use a more complex layout, use the constructors that also takes a field id. That field id should reference a TextView in the larger layout resource.

So, your custom adapter class could be somthing like:

public class CustomAdapter extends ArrayAdapter {
    private final Activity activity;
    private final List list;

    public CustomAdapter(Activity activity, ArrayList<Restaurants> list) {
        this.activity = activity;
        this.list = list;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        View rowView = convertView;
        ViewHolder view;

        if(rowView == null)
        {
            // Get a new instance of the row layout view
            LayoutInflater inflater = activity.getLayoutInflater();
            rowView = inflater.inflate(R.layout.rowlayout, null);

            // Hold the view objects in an object, that way the don't need to be "re-  finded"
            view = new ViewHolder();
            view.retaurant_name= (TextView) rowView.findViewById(R.id.restaurantname);
            view.restaurant_address= (TextView) rowView.findViewById(R.id.textView1);

            rowView.setTag(view);
        } else {
            view = (ViewHolder) rowView.getTag();
        }

        /** Set data to your Views. */
        Restaurants item = list.get(position);
        view.retaurant_name.setText(item.getTickerSymbol());
        view.restaurant_address.setText(item.getQuote().toString());

        return rowView;
    }

    protected static class ViewHolder{
        protected TextView retaurant_name;
        protected TextView restaurant_address;
    }
}

And your Restaurant.java class could as simple as I describe below:

public class Restaurants {
    private String name;
    private String address;

    public Restaurants(String name, String address) {
        this.name = name;
        this.address = address;
    }
    public void setName(String name) {
        this.name= name;
    }
    public String getName() {
        return name;
    }
    public void setAddress(String address) {
        this.address= address;
    }
    public String getAddress() {
        return address;
    }
}

Now, in you main activity just bind you list with some data, like;

/** Declare and initialize list of Restaurants. */
ArrayList<Restaurants> list = new ArrayList<Restaurants>();

/** Add some restaurants to the list. */
list.add(new Restaurant("name1", "address1"));
list.add(new Restaurant("name2", "address2"));
list.add(new Restaurant("name3", "address3"));
list.add(new Restaurant("name4", "address4"));
list.add(new Restaurant("name5", "address5"));
list.add(new Restaurant("name6", "address6"));

At this point you're able to set the custom adapter to your list

ListView lv = (ListView) findViewById(R.id.mylist);

CustomAdapter adapter = new CustomAdapter(YourMainActivityName.this, list);
lv.setAdapter(adapter);

This is all and it should work nicelly, but I strongly recommend you to google for some better alternatives to implement others Adapters.