Lazy loading onclick listview

Question

I am doing a lazyload code for list view in which i am getting a text and image url in json and putting them in the listview.

The image and text are both shown accordingly as what i wanted.

The problem i am facing is when the list is scrolled downwards or upwards the index of the view gets disturbed.

Suppose if have 10 elements in my list with images previewing sideways. Initially i can see 4 elements on whose onclick action works fine, But when i scrolldown and click the 7th ir 8th element the indexing gets disturbed and results in null pointer exception.

   l2.setOnItemClickListener(new OnItemClickListener() {
    @Override
     public void onItemClick(AdapterView<?> parent, View view,int position, long id) 
        {
            View curr = parent.getChildAt((int) id);
            TextView c = (TextView)curr.findViewById(R.id.text);
            String sel_item = c.getText().toString();
            Intent intent = new Intent(SubCatListActivity.this,GridActivity.class);
             adapter.imageLoader.clearCache();
            intent.putExtra("gall", sel_item);
            intent.putExtra("cate", cate);
            startActivity(intent);
            Toast.makeText(SubCatListActivity.this,sel_item, Toast.LENGTH_SHORT).show();

         }});

the problem seems to be with the textview as i am not able to get the desired text on the onclick of list.

If i touch the 6th element i get the text of 7th or 8th item.

please don't yell at us in the title... – WarrenFaith Jun 05 '13 at 09:57 — WarrenFaith, Jun 05 '13 at 09:57

score 1 · Accepted Answer · answered Jun 05 '13 at 10:02

You can try by changing this line to

TextView c = (TextView) view.findViewById(R.id.text);

and remove your first line View curr = parent.getChildAt((int) id);

l2.setOnItemClickListener(new OnItemClickListener() {
@Override
 public void onItemClick(AdapterView<?> parent, View view,int position, long id) 
    {

        TextView c = (TextView) view.findViewById(R.id.text);
        String sel_item = c.getText().toString();
        Intent intent = new Intent(SubCatListActivity.this,GridActivity.class);
         adapter.imageLoader.clearCache();
        intent.putExtra("gall", sel_item);
        intent.putExtra("cate", cate);
        startActivity(intent);
        Toast.makeText(SubCatListActivity.this,sel_item, Toast.LENGTH_SHORT).show();

     }});

score 1 · Answer 2 · answered Jun 05 '13 at 10:03

1

The onItemClick method passes in the View you are clicking on. In your code above you have it named "view". parent.getChildAt((int)id) is not going to give you the right view.

answered Jun 05 '13 at 10:03

Bradley Campbell

9,298
6
37
47

score 1 · Answer 3 · answered Jun 05 '13 at 10:04

1

Try to switch between positions and get textView text as:

(TextView) view.getText().toString();

you will get the right textView this way

answered Jun 05 '13 at 10:04

Marcis

71
6

score 1 · Answer 4 · answered Jun 05 '13 at 10:11

You should use the view that you get from the parameters:

TextView c = (TextView)view.findViewById(R.id.text);

  l2.setOnItemClickListener(new OnItemClickListener() {
 @Override
 public void onItemClick(AdapterView<?> parent, View view,int position, long id) 
    {

        TextView c = (TextView)view.findViewById(R.id.text);
        String sel_item = c.getText().toString();
        Intent intent = new Intent(SubCatListActivity.this,GridActivity.class);
         adapter.imageLoader.clearCache();
        intent.putExtra("gall", sel_item);
        intent.putExtra("cate", cate);
        startActivity(intent);
        Toast.makeText(SubCatListActivity.this,sel_item, Toast.LENGTH_SHORT).show();

     }});

Lazy loading onclick listview

4 Answers4