ListView Child access problem

Question

I currently have the following adapter to set up my listview:

    public class MyListAdapter extends ArrayAdapter<String> {

    private Context mContext;

    public MyListAdapter(Context context, int resource, int textViewResourceId,String[] objects) {
        super(context, resource, textViewResourceId, objects);
        // TODO Auto-generated constructor stub
    }


    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        // TODO Auto-generated method stub
        Drawable cross = getResources().getDrawable(R.drawable.cross);
        Drawable arrow = getResources().getDrawable(R.drawable.arrow);

        View row = convertView;

         if(row == null){
          LayoutInflater inflater= getLayoutInflater();
          row = inflater.inflate(R.layout.list_view_format2, parent, false);
         }

         TextView text =(TextView)row.findViewById(R.id.list_content2);
         text.setText(list[position]);

         ImageView image = (ImageView)row.findViewById(R.id.rightArrow);
         TextView check = (TextView)row.findViewById(R.id.checker);

         if (item != null && text.getText().toString().equals(item)){
             text.setBackgroundDrawable(cross);
             image.setImageDrawable(arrow);
             check.setText("cross");
         }


         return row;

    }
}

R.layout.list_view_format2: a custom ListView format. It contains an ImageView and a TextView R.id.list_content2: *Id of the Text View within R.id.list_view_format2*

I am trying to change certain parts of a child if the search is successful. However, instead of only one child being modified, when I scroll up or down a ListView the layout of the other children gets modified as well. I don't exactly get what is happening. Can someone please explain?

what is item? it seems `(item != null && text.getText().toString().equals(item))` is always true — Sherif elKhatib, Aug 10 '11 at 00:14
item is a String type that I have hard-coded for testing purposes as: String item = "4 gallons of milk"; — Abhijit, Aug 10 '11 at 00:24

score 1 · Answer 1 · answered Aug 10 '11 at 00:16

1

ArrayAdatper is a very limited class, try moving over to SimpleAdapter which has several more features which will make what you want to do easier. Instead of overriding getView() look at the features of SimpleAdapter.ViewBinder which will allow you to do extensive modifications to the list items based on the underlying data. Here you will be able to make only certain list items to appear different than the others.

answered Aug 10 '11 at 00:16

Dan S

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Thank you! Could you please provide a simple example, so that I can build up on it. I looked at the links but being a newbie, I am having difficulty in using them. – Abhijit Aug 10 '11 at 00:23
Checkout this tutorial for the [SimpleCursorAdapter](http://developer.android.com/resources/samples/ApiDemos/src/com/example/android/apis/view/List3.html), the only difference that you need to worry about is the underlying data is from a `List>` instead of a `Cursor`. – Dan S Aug 10 '11 at 01:12
I tried to use the SimpleAdapter but without much success. However, I managed to find a solution for what I had intended to achieve. I have posted the solution as well. – Abhijit Aug 11 '11 at 00:07
Again, thank you for the response. For the past couple of months, I have been working on android quite a bit. Through this course I have understood adapters far better. Here is a link that might interest you: http://stackoverflow.com/questions/6395246/choose-between-arrayadapter-and-simpleadapter – Abhijit Nov 28 '11 at 16:39

score 0 · Accepted Answer · answered Aug 11 '11 at 00:12

I figured it out. I just had to set the others to null! I did that in the else block. Now it works perfectly.

  @Override
   public View getView(int position, View convertView, ViewGroup parent) {
         // TODO Auto-generated method stub
         Drawable cross = getResources().getDrawable(R.drawable.cross);
         Drawable arrow = getResources().getDrawable(R.drawable.arrow);

     View row = convertView;

     if(row == null){
      LayoutInflater inflater= getLayoutInflater();
      row = inflater.inflate(R.layout.list_view_format2, parent, false);
     }

     TextView text =(TextView)row.findViewById(R.id.list_content2);
     text.setText(list[position]);

     ImageView image = (ImageView)row.findViewById(R.id.rightArrow);
     TextView check = (TextView)row.findViewById(R.id.checker);

     if (item != null && text.getText().toString().equals(item)){
         text.setBackgroundDrawable(cross);
         image.setImageDrawable(arrow);
         check.setText("cross");
     }



   else {    
      text.setBackgroundDrawable(null);
      image.setImageDrawable(null);
      check.setText("none");
   }


  return row;

}

ListView Child access problem

2 Answers2