OnItemClickListener无法在Gridview中工作

Question

我想用一些图片显示gridview。我成功地在gridview中显示图像，但是当我想单击图像以便在Toast中显示文本时，它什么都没发生。 这是我的示例代码。

GridView gridView = (GridView)layout.findViewById(R.id.emoticons_grid);     
gridView.setAdapter(new EmoticonsGridAdapter(getApplicationContext()));

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

然后是适配器。

public EmoticonsGridAdapter(Context c)
    { context = c;

    } 
    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return imageIDs.length; }

    @Override
    public Object getItem(int position) {
        // TODO Auto-generated method stub
        return imageIDs[position]; 
    }
    @Override
    public long getItemId(int position) {
        // TODO Auto-generated method stub
        return 0; 
    }
    @SuppressLint("UseValueOf")
    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        // TODO Auto-generated method stub
        ImageView imageView; 
        if (convertView == null) {
            imageView = new ImageView(context);
            imageView.setLayoutParams(new GridView.LayoutParams(80, 80)); 
            imageView.setScaleType(ImageView.ScaleType.CENTER_CROP); 
            imageView.setPadding(8, 8, 8, 8); 
            } 
        else { 
            imageView = (ImageView) convertView; 
        } 
            imageView.setImageResource(imageIDs[position]);

        return imageView; 
    }

    private Integer[] imageIDs = { 
            R.drawable.emo1, 
            R.drawable.emo2, 
            R.drawable.emo3, 
            R.drawable.emo4, 
            R.drawable.emo5, 
            R.drawable.emo6, 
            R.drawable.emo7, 
            R.drawable.emo8, 
            R.drawable.emo9, 
            R.drawable.emo10,
            R.drawable.emo12, 
            R.drawable.emo13, 
            R.drawable.emo14, 
            R.drawable.emo15, 
            R.drawable.emo16, 
            R.drawable.emo17, 
            R.drawable.emo18, 
            R.drawable.emo19, 
            R.drawable.emo20
    };

你介意解释什么是错的吗？