更改列表视图内的文本视图文本时出现的问题

Question

I'm new to this android development and having issues while setting the text of textview inside listview.

Issue:

Listview in activity 1

====================
Model
====================
Color
====================
Style
====================
Make
====================

When I click on "Model" view in listview. the below shows up

Listview in activity 2

====================
Toyota
====================
Jaguar
====================
Honda
====================
Suburu
====================

Result In activity 1

====================
Model
====================
Color -------------- Toyota
====================
Style
====================
Make
====================

What I was looking for:

====================
Model -------------- Toyota
====================
Color
====================
Style
====================
Make
====================

Here the initial activity. when I click on "Model" inside listview another activity will be shown with list of car models. (new activity is called using startactivtiyforresult())

In the second activity when I click on any model name it closes this current activity and passes the selected model name to first activity. this model name is set to the textview in OnActivityResult method

My CustomAdapter

class CustomAdapter extends ArrayAdapter<String> {

    Context context;
    String[] titles;


    public CustomAdapter(Context context, String[] titles) {
        super(context, R.layout.dashboard_row_layout, R.id.row_textview, titles);

        this.context = context;
        this.titles = titles;
    }

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

        View row = convertView;
        ViewHolder holder;
        if(row==null)
        {
            LayoutInflater inflater = (LayoutInflater)context.getSystemService(context.LAYOUT_INFLATER_SERVICE);
            row = inflater.inflate(R.layout.dashboard_row_layout, parent, false);
            holder = new ViewHolder(row);
            row.setTag(holder);
        }
        //((TextView)row.findViewById(R.id.row_textview)).setText(titles[position]);
        else
        {
            holder = (ViewHolder)row.getTag();
        }
        holder.textview.setText(titles[position].toString());

        return row;
    }
}

class ViewHolder
{
    TextView textview;
    ViewHolder(View v)
    {
        textview = (TextView) v.findViewById(R.id.row_textview);
    }
}

OnActivityResultMethod

@Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        switch (resultCode)
            {
                case Activity.RESULT_OK:
                    //selectedModel = data.getStringExtra("response");
                      setDateTextView.setText(data.getStringExtra("response"));
            }
    }

OnCreateView of the Fragment

@Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        final View rootView = inflater.inflate(R.layout.fragment_vehicle_information, container, false);

        SeparatedListAdapter adapter = new SeparatedListAdapter(this.getActivity());
        adapter.addSection("Plate Information", new CustomAdapter(this.getActivity(),getResources().getStringArray(R.array.plateInformationArrayList)));
        adapter.addSection("Vehicle Information", new CustomAdapter(this.getActivity(),getResources().getStringArray(R.array.vehicleInformationArrayList)));
        ((ListView)rootView.findViewById(R.id.veh_information_listView)).setAdapter(adapter);

        //Click Listener for listview with custom view
        ((ListView)rootView.findViewById(R.id.veh_information_listView)).setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                if(((TextView)view.findViewById(R.id.row_textview)).getText().toString().equalsIgnoreCase("Expiration")){
                    DateDialog dialog = new DateDialog(getActivity(), (TextView)view.findViewById(R.id.statename_textView));
                    dialog.returnDateDialog().show();
                }
                else if(((TextView)view.findViewById(R.id.row_textview)).getText().toString().equalsIgnoreCase("Model")){
                    setDateTextView = (TextView)view.findViewById(R.id.statename_textView);
                    startActivityForResult(new Intent(getActivity(), VehicleInformationDetails.class),  1);
                }

            }
        });


        return rootView;
    }

SecondActivity

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

    View rootView = inflater.inflate(R.layout.fragment_searchable_listview, container, false);
    ListView listview = (ListView)rootView.findViewById(R.id.searchable_listView);
    MyAdapter adapter = new MyAdapter(context, array);
    listview.setAdapter(adapter);
    listview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            TextView textView = (TextView)view.findViewById(R.id.list_item_title);
            Intent returnIntent = new Intent();
            returnIntent.putExtra("response", textView.getText().toString());
            getActivity().setResult(Activity.RESULT_OK, returnIntent);
            getActivity().finish();
        }
    });
    SetActionBarTitle(this.actionBarTitle);

    return rootView;

}

Hope this explanation is helpful. Please help me.

Answer 1

It is not reliable to try to directly change the text of a text view that's inside a list item from outside of the adapter. For one thing, the view will not be matching the backing data of your adapter. Also, your adapter does not attempt to clear any existing contents of the secondary text view, so you are going to run into a lot of unusual problems like this as your list view recycles its views.

So get rid of all the lines referring to setDateTextView . Instead, you need a custom class that represents all of the possible data for a list item, like this:

public class MyListItem {
    public String title;
    public String state;

    public MyListItem(String title){
        this(title, "");
    }

    public MyListItem(String title, String state){
        this.title = title;
        this.state = state;
    }
}

Then use this as the object type of your custom adapter:

class CustomAdapter extends ArrayAdapter<MyListItem> {

    public CustomAdapter(Context context, MyListItem[] listItems) {
        super(context, R.layout.dashboard_row_layout, listItems);
    }

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

        View row = convertView;
        ViewHolder holder;
        if(row==null)
        {
            LayoutInflater inflater = (LayoutInflater)getContext().getSystemService(context.LAYOUT_INFLATER_SERVICE);
            row = inflater.inflate(R.layout.dashboard_row_layout, parent, false);
            holder = new ViewHolder(row);
            row.setTag(holder);
        }
        else
        {
            holder = (ViewHolder)row.getTag();
        }

        holder.titleTextview.setText(getItem(position).title);
        holder.stateTextview.setText(getItem(position).state);

        return row;
    }
}

class ViewHolder
{
    TextView titleTextview;
    TextView stateTextview;
    ViewHolder(View v)
    {
        titleTextview= (TextView) v.findViewById(R.id.row_textview);
        stateTextview= (TextView) v.findViewById(R.id.statename_textView);
    }
}

Finally, in your onActivityResult() , tell the adapter to change the value of the content array for the appropriate row. You'll have to set these variables up as member variables, but do it something like this:

switch (resultCode)
{
    case Activity.RESULT_OK:
        mListAdapter.getItem(mModelItemPosition).state = data.getStringExtra("response");
        mListAdapter.notifyDataSetChanged();
        break;
}