GridView shows only two columns

Question

I programmatically created a GridView of images to be used inside a Dialog. If I set the columns to autofit, I always get exactly two columns, whatever the size of the images is and whatever the screen size is. If I force the columns to a fixed number, then it works, but I cannot avoid the images to overlap on certain screen sizes, so an automatic management of the number of columns would be much better. Even more, when I try to set streching, it simply does not show anything!

My ImageAdapter:

public class ImageAdapter extends BaseAdapter {
private Context mContext;

// Constructor
public ImageAdapter(Context c){
    mContext = c;
}

public int getCount() {
    return (IconC.Res.length);
}

public Object getItem(int position) {
    return (IconC.Res[position]);
}

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

public View getView(int position, View convertView, ViewGroup parent) {
    ImageView imageView;
    if (convertView == null) {
        imageView = new ImageView(mContext);
        imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
        imageView.setLayoutParams(new GridView.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
    } else {
        imageView = (ImageView) convertView;
    }
    imageView.setImageResource(IconC.Res[position]);
    return (imageView);
}
 }

And the function that creates the Dialog (that is called elsewhere with a .show() )

    private void createPopUp() {
    d_icons = new Dialog(this);
    GridView gv_icons = new GridView(this);

//  gv_icons.setNumColumns(GridView.AUTO_FIT);  // autofit disabled, shows ONLY TWO COLUMNS
    gv_icons.setNumColumns(4); // instead, autofit forced, now it works, but I don't want it fixed!
    gv_icons.setGravity(Gravity.CENTER);
    gv_icons.setHorizontalSpacing(3);
    gv_icons.setVerticalSpacing(1);
//  gv_icons.setStretchMode(GridView.STRETCH_SPACING);  // stretching disabled, shows ZERO COLUMNS
    gv_icons.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
    gv_icons.setAdapter(new ImageAdapter(this));
    gv_icons.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        public void onItemClick (AdapterView<?> parent, View view, int position, long id) {
            eventIcons.set(selectedItem, position);
            updateEventView();
            d_icons.dismiss();
        }
    });

    d_icons.setTitle(R.string.text_chooseicon);
    d_icons.addContentView(gv_icons, new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
    d_icons.setCancelable(true);
}

Can anyone spot why this happens? Thank you!!

Here's how it appears with the 4 fixed columns: i50.tinypic.com/2ebdfec.png

Here's how it is with the autofit: i50.tinypic.com/25jxo9s.png

Here is the layout with autofit on a horizontal tab: i49.tinypic.com/23r7qj5.png

Answer 1

This post answers your question: Android: How does GridView auto_fit find the number of columns?

In order for the auto_fit to work you need to specify the column width: gridView.setColumnWidth( width );

Answer 2

Actually it depends on device size. As you first tested your application with making the no of columns fixed, grid displays only 2 columns because the space for the 3 image is not enough large so that it can fit in.