Read text from a text view inside a list row by id

Question

I have a list which is populated by my database. Each list row has a text view and two buttons. I want to cycle through all list rows and check the text of each text view that is inside the list and change one of the buttons backgrounds depending on the text read in.

Here is my code:

Button fav, trash;
ListView lv;
TextView tv;
Cursor data;
CursorAdapter dataSource;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        this.requestWindowFeature(Window.FEATURE_NO_TITLE);
        super.onCreate(savedInstanceState);
        setContentView(R.layout.hs);


        tv = (TextView) this.findViewById(R.id.first);
        trash = (Button) this.findViewById(R.id.trashButton);
        fav = (Button) this.findViewById(R.id.favButton);



        data.moveToNext();

        dataSource = new SimpleCursorAdapter(this, R.layout.phrasebook, data,
                fields, new int[] { R.id.first}, 0);

        lv = (ListView) findViewById(R.id.list_view);

        lv.setAdapter(dataSource);

You can see that the list is populated by the data source and the text view "first" is filled with strings. I want to loop through each list row read the text view and then change the button background depending on what the text is. My problem is how do you get the id's of the text views and buttons?

I read up and discovered get child and parent but not sure if this is along the right track. I thought if I could access the list rows by id then access its children then I could do it this way but I don't know if this is possible. Any advice is appreciated.

I have experimented with creating a custom adapter, I have it working and also found a way to access positions, I am hoping to exploit this to maybe access the text views.

public class AdapterEx extends SimpleCursorAdapter {

private Context mContext;
private Context appContext;
private int layout;
private Cursor cr;
private final LayoutInflater inflater;
TextView tv;

public AdapterEx(Context context,int layout, Cursor c,String[] from,int[] to) {
    super(context,layout,c,from,to);
    this.layout=layout;
    this.mContext = context;
    this.inflater=LayoutInflater.from(context);
    this.cr=c;
}

@Override
public View newView (Context context, Cursor cursor, ViewGroup parent) {
        return inflater.inflate(layout, null);
}

@Override
public void bindView(View view, Context context, Cursor cursor) {
    super.bindView(view, context, cursor);
     tv=(TextView)view.findViewById(R.id.first);
     if(cursor.getPosition()%2==1) {
         view.setBackgroundColor(Color.rgb(206, 43, 55));
          }
          else {
              view.setBackgroundColor(Color.rgb(0, 146, 70));
          }

}

}

Answer 1

Here is an example:

public class AdapterEx extends ArrayAdapter<String>
{

//You are going to pass a array of String, that you'll use at the textview.

Context context;
int resourceId;
ArrayList<String> tempStrings;

public AdapterEx ( Context context, int resourceId, ArrayList<String> tempStrings) 
{

    super( context, resourceId, tempStrings);

    this.context = context;
    this.resourceId = resourceId;
    this.tempStrings= tempStrings;

}

//In this class you'll declare everything that you'll use from your xml file, like        textview, buttons and etc.
private class ViewHolder
{

    TextView textViewsHere;

    Button buttonsHere;

}

@Override
public View getDropDownView(int position, View convertView,ViewGroup parent) 
{

    return getCustomView(position, convertView, parent);

}

@Override
public View getView( int position, View convertView, ViewGroup parent )
{

    return getCustomView(position, convertView, parent);

}

private View getCustomView( int position, View convertView, ViewGroup parent )
{

    View row = convertView;

    ViewHolder holder = null;

    if( row == null )
    {

        LayoutInflater mInflater = ( ( Activity ) context ).getLayoutInflater();
        row = mInflater.inflate( resourceId, parent, false );

        holder = new ViewHolder();

        //Now you are going to link from layout using your holder. Example:
        holder.textViewsHere = (TextView) row.findViewById( R.id.textViewsHere );

        row.setTag( holder );

    }else
    {

        holder = ( ViewHolder ) row.getTag();

    }

    //After doing the link between java code and xml.
    //You are going to set the value at the textView, buttons and whatever you want.
    //You pass to this class a arrayList<String> with the values that you want at the textview.

    String valueForTheTextView = tempStrings.get(position);

    holder.textViewsHere.setText( valueForTheTextView  );

    if( valueForTheTextView .equals("whatYouWantHere"))
    {

         button.changeTheButtonBackground(); //Example

    }

    return row;

}

}

To use that you do the same with other adapater something like that AdapterEx temp = new AdapterEx( activity.this, R.layout.YOUHAVETOCREATEYOURLAYOUT, theDataHere );

Answer 2

I disagree with Jonas452. If your data is coming from a DB, it does not make sense to force convert your data to an ArrayList simply to use an ArrayAdapter. That defeats the purpose of why CursorAdapter's exist.

Jonas452 is correct that you need to implement a custom view (which is totally possible with CursorAdapters)...however they work slightly different. Here's a great simple example showing and explaining how to do what Jonas452 talked about but with using a SimpleCursorAdapter:

Custom CursorAdapter

Once you have your bindView() method implemented, you will use this method to actually assign the data from the cursor into the TextView. Because you have the data on hand, you can choose how to render the buttons right there. The Cursor will always be at the correct row position to pull the data for. That's because bindView will be called for every item displayed in your list. The cursor passed in there will always represent the data for that given item. So whichever column the string is stored in the cursor, is the string value to use to determine what to do with your buttons.

@Override
public void bindView(View view, Context context, Cursor cursor) {
   tv=(TextView)view.findViewById(R.id.first);
   //...find your other views

   String text = cursor.getString(cursor.getColumnIndex("Your Column Name"));
   tv.setText(text);
   if (text.equals("test here")) {
       //...change button stuff
   } else {
       //...change button stuff
   }

   //....do whatever else you may need
}

Addendum, once you feel comfortable with this, I suggest learning about the ViewHolder paradigm. It's a highly recommended approach with any custom adapter. Here's another link demonstrating on using it with CursorAdapters.