I'm trying to write BaseAdapter to my GrivView but in
public View getView(int position, View convertView, ViewGroup parent) { ... }
the position while rendering next elements is:
visible elements --------------- | 1 2 3 | | 4 5 6 | <--- screen | 7 8 9 | --------------- nonvisible elements | 1 2 3 | <-- below visible area | 4 5 6 |
where real is:
visible elements --------------- | 1 2 3 | | 4 5 6 | | 7 8 9 | --------------- nonvisible elements | 10 11 12 | | 13 14 15 |
I'm aware it's correct behaviour (it counts only visible elements), but how to get the real position of item on list? Or how to know which layout should I return?
EDIT: However the returned number are much more random than I showed, even on screen.
Using BaseAdapter exactly like Google Documentatnion shows works fine.
My problem was:
I should to use ViewHolder as following:
public View getView(int position, View convertView, ViewGroup parent) { // create holder ViewHolder holder; // check if layout exists if (convertView == null) { // if it's not recycled, initialize some LayoutInflater inflater = LayoutInflater.from(mContext); convertView = (LinearLayout) inflater.inflate(R.layout.card_prev, null); // Create layout elements ImageView image = (ImageView) convertView .findViewById(R.id.imageViewThumbnail); TextView desc = (TextView) convertView .findViewById(R.id.textViewDescription); // Place layout elements in holder holder = new ViewHolder(); holder.id = position; holder.preview = image; holder.text = desc; convertView.setTag(holder); } else { // Get existing holder holder = (ViewHolder) convertView.getTag(); } // Update layout here using layout elements from holder String imageName = "image_" + (position + 1); final int imageId = mContext.getResources().getIdentifier(imageName, "drawable", "com.myapp"); holder.text.setText("" + (position+1)); holder.preview.setImageResource(imageId); holder.preview.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { Intent fullScreenIntent = new Intent(v.getContext(), FullScreenImage.class); fullScreenIntent.putExtra("imageRes", imageId); MainMenuActivity.currentShownActivity .startActivity(fullScreenIntent); } }); return convertView; }
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