Question

I am trying to create a nice layout for my list items, but my code only works when it is simplified like this:

<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:padding="10dp"
    android:textSize="16sp" >
</TextView>

When I add a little bit more it compiles and runs but it force closes on start and gives me the error ArrayAdapter requires ID to be a TextView:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="?android:attr/listPreferredItemHeight"
    android:padding="6dip" >

    <ImageView
        android:id="@+id/icon1"
        android:layout_width="wrap_content"
        android:layout_height="fill_parent"
        android:layout_alignParentBottom="true"
        android:layout_alignParentTop="true"
        android:layout_marginRight="6dip"
        android:src="@drawable/ic_launcher" />

    <TextView
        android:id="@+id/secondLine"
        android:layout_width="fill_parent"
        android:layout_height="26dip"
        android:layout_alignParentBottom="true"
        android:layout_alignParentRight="true"
        android:layout_toRightOf="@id/icon1"
        android:ellipsize="marquee"
        android:singleLine="true"
        android:text="Some more information" />

    <TextView
        android:id="@+id/textView1"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_above="@id/secondLine"
        android:layout_alignParentTop="true"
        android:layout_alignWithParentIfMissing="true"
        android:layout_toRightOf="@id/icon1"
        android:gravity="center_vertical"
        android:text="Some Information" />

    <ImageView
        android:id="@+id/icon2"
        android:layout_width="wrap_content"
        android:layout_height="fill_parent"
        android:layout_alignParentRight="true"
        android:layout_alignParentTop="true"
        android:layout_marginRight="6dip"
        android:src="@drawable/ic_launcher" />

</RelativeLayout>

and

public class FirstLoginActivity extends ListActivity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        String[] testcontacts = getResources().getStringArray(
                R.array.testcontacts_array);
        setListAdapter(new ArrayAdapter<String>(this, R.layout.list_items,
                testcontacts));

        ListView lv = getListView();
        lv.setTextFilterEnabled(true);

        lv.setOnItemClickListener(new OnItemClickListener() {
            public void onItemClick(AdapterView<?> parent, View view,
                    int position, long id) {
                // When clicked, show a toast with the TextView text
                Toast.makeText(getApplicationContext(),
                        ((TextView) view).getText(), Toast.LENGTH_SHORT).show();
            }
        });
    }

I am pretty sure I’m doing this right, I’ve been through numerous tutorials and I’ve found that the fastest and most efficient way is to create a static ViewHolder class. One of the tutorials tried accessing the data directly which is what I was trying to do. I’m still a little confused on how to do so.

    public class FirstLoginActivity extends ListActivity {
    Context mContext;
    List mList;

    String[] testcontacts = getResources().getStringArray(
            R.array.testcontacts_array);

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setListAdapter(new ArrayAdapter<String>(this, R.layout.list_items,
                testcontacts));

        ListView lv = getListView();
        lv.setTextFilterEnabled(true);

        lv.setOnItemClickListener(new OnItemClickListener() {
            public void onItemClick(AdapterView<?> parent, View view,
                    int position, long id) {
                // When clicked, show a toast with the TextView text
                Toast.makeText(getApplicationContext(),
                        ((TextView) view).getText(), Toast.LENGTH_SHORT).show();
            }
        });
    }



    public View getView(int position, View convertview, ViewGroup parent) {
        ViewHolder holder;
        View v = convertview;
        if (v == null) {
            LayoutInflater inflater = (LayoutInflater) LayoutInflater
                    .from(mContext);
            v = inflater.inflate(R.layout.list_items, null);
            holder = new ViewHolder();
            holder.firstLine = (TextView) v.findViewById(R.id.firstLine);
            holder.secondLine = (TextView) v.findViewById(R.id.secondLine);
            holder.icon1 = (ImageView) v.findViewById(R.id.icon1);
            holder.icon2 = (ImageView) v.findViewById(R.id.icon2);
            v.setTag(holder);
        } else {
            holder = (ViewHolder) v.getTag();
        }
        holder.firstLine.setText(testcontacts[position]);
        holder.secondLine.setText(testcontacts[position]);
        // holder.icon1.setImageBitmap((position & 1) == 1 ? mIcon1: mIcon2);
        //call the images directly?
        return v;
    }

    static class ViewHolder {
        TextView firstLine;
        TextView secondLine;
        ImageView icon1;
        ImageView icon2;

    }
}

Answer 1

You are probably using something like this (here the doc):

ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, R.layout.layout_1, values);

in that case your layout must be a simple layout with a TextView.

If you wanna use your own layout you need to write a custom adapter.