Question

Error – Market cannot be resolved or is not a field.
News cannot be resolved or is not a field.
Weather cannot be resolved or is not a field.

I am trying an example on GridView. I added images named Market, News and Weather to res>>drawable-mdpi>> folder. But Eclipse fails to recognize it. The images are in *jpeg * format. What may be wrong? Can you please help? Here I am posting the code

public class MainActivity extends Activity 
{
    // Images to display-----------------------//
    Integer[] imageIds = {
            R.drawable.Market,
            R.drawable.News,
            R.drawable.Weather
    };
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) 
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        GridView gridView = (GridView) findViewById(R.id.gridview);// Bring gridView into context from main.xml
        gridView.setAdapter(new ImageAdapter(this)); 

        gridView.setOnItemClickListener(new OnItemClickListener()
        {
        public void onItemClick(AdapterView<?> parent,
        View v, int position, long id)
        {
            Toast.makeText(getBaseContext(), "pic " + (position + 1) + " selected",        Toast.LENGTH_SHORT).show();
        }
        });
     }

    public class ImageAdapter extends BaseAdapter
    {
        private Context context; // Context class object - context

        public ImageAdapter(Context c)
        {
            context = c;
        }

        //return number of images
        public int getCount()
        {
            return imageIds.length;
        }

        public Object getItem(int position)     // return type of getItem method is an Object
        {
            return position;
        }

        public long getItemId(int position)
        {
            return position;
        }

        //returns an ImageView view--------------
        public View getView(int position, View convertView, ViewGroup parent)
        {
            ImageView imageView;
            if(convertView == null)
            {
                imageView = new ImageView(context);
                imageView.setLayoutParams(new GridView.LayoutParams(85, 85));
                imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
                imageView.setPadding(5, 5, 5, 5);
            }
            else
            {
                imageView = (ImageView) convertView;
            }
            imageView.setImageResource(imageIds[position]);
            return imageView;
        }       
    }    
}

Answer 1

I tried creating a resource with name Weather (a picture placed in drawable-mdpi) and I got

res\drawable-mdpi\Weather.jpg: Invalid file name: must contain only
[a-z0-9_.]

in Eclipse. I thought the resource names should be snake-styled by restriction, but I found this thread where the guy states that camel case is also all right. This means that the only restriction is not to have the first letter capital.