Android - Implementing your own adapter

The following uses two images "no.png" and "ok.png". I placed it in the "res/drawable-mdpi" folder. You must create your own icons. In case you do not find any icons just copy "icon.png" and use a drawing program to change it a little bit.

Create the class MySimpleArrayAdapter which will serve as our adapter.

package de.vogella.android.listactivity;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.TextView;

public class MySimpleArrayAdapter extends ArrayAdapter<String> {
  private final Context context;
  private final String[] values;

  public MySimpleArrayAdapter(Context context, String[] values) {
    super(context, R.layout.rowlayout, values);
    this.context = context;
    this.values = values;
  }

  @Override
  public View getView(int position, View convertView, ViewGroup parent) {
    LayoutInflater inflater = (LayoutInflater) context
        .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    View rowView = inflater.inflate(R.layout.rowlayout, parent, false);
    TextView textView = (TextView) rowView.findViewById(R.id.label);
    ImageView imageView = (ImageView) rowView.findViewById(R.id.icon);
    textView.setText(values[position]);
    // Change the icon for Windows and iPhone
    String s = values[position];
    if (s.startsWith("Windows7") || s.startsWith("iPhone")
        || s.startsWith("Solaris")) {
      imageView.setImageResource(R.drawable.no);
    } else {
      imageView.setImageResource(R.drawable.ok);
    }

    return rowView;
  }
} 

To use this adapter, change the activity to the following.

package de.vogella.android.listactivity;

import android.app.ListActivity;
import android.os.Bundle;

public class MyListActivity extends ListActivity {
  public void onCreate(Bundle icicle) {
    super.onCreate(icicle);
    String[] values = new String[] { "Android", "iPhone", "WindowsMobile",
        "Blackberry", "WebOS", "Ubuntu", "Windows7", "Max OS X",
        "Linux", "OS/2" };
    MySimpleArrayAdapter adapter = new MySimpleArrayAdapter(this, values);
    setListAdapter(adapter);
  }

} 

If you run this example you should get a list with different icons for the certain elements.

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