Question

Possible Duplicate:
How to refresh Android listview?

I am looking for using Refresh button refreshing the listview data.. DES:In my app there is refresh button when i onclick on it Listview data which coming from server must get refresh & show update listview data.
And I have no idea how to do that. plz suggest me with example.. Thanks in advance. below is my code.

Mainactivity.java

listView = (ListView) findViewById(R.id.homelistView);
listView.setTextFilterEnabled(true);   
final EfficientAdapter objectAdapter = new EfficientAdapter(this);
listView.setAdapter(objectAdapter);


Button refreshButton= (Button)findViewById(R.id.refreshButton);
 refreshButton.setOnClickListener(new OnClickListener() {
    @Override
    public void onClick(View v) {
    objectAdapter.notifyDataSetChanged();

    }
});

EfficientAdapter.java

public static class EfficientAdapter extends BaseAdapter {
    private LayoutInflater mInflater;
    private Context context;

    public EfficientAdapter(Context context) {
        mInflater = LayoutInflater.from(context);
        this.context=context;

    }


    public int getCount() {
        return CountriesList.name.length;
    }

    public Object getItem(int position) {

        return position;
    }

    public long getItemId(int position) {
        return position;
    }

    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder;
        if (convertView == null) {
            convertView = mInflater.inflate(R.layout.homemplebrowview, null);
            holder = new ViewHolder();
            holder.text1 = (TextView) convertView
                    .findViewById(R.id.name);
            holder.text2 = (TextView) convertView
                    .findViewById(R.id.mrn);
            holder.text3 = (TextView) convertView
                    .findViewById(R.id.date);
            holder.text4 = (TextView) convertView
                    .findViewById(R.id.age);
            holder.text5 = (TextView) convertView
                    .findViewById(R.id.gender);
            holder.text6 = (TextView) convertView
                    .findViewById(R.id.wardno);
            holder.text7 = (TextView) convertView
                    .findViewById(R.id.roomno);
            holder.text8 = (TextView) convertView
                    .findViewById(R.id.bedno);                  
            holder.btnList = (Button)convertView.findViewById(R.id.listbutton);
         //   holder.btnList.setOnClickListener(this);

            holder.btnList.setOnClickListener(new OnClickListener() {

                @Override
                public void onClick(View v) {                       
                    Intent next=new Intent(context, SeviceDetails.class);
                    context.startActivity(next);
                }
            });


            convertView.setTag(holder);
        } else {
            holder = (ViewHolder) convertView.getTag();
        }

        holder.text1.setText(CountriesList.name[position]);
        holder.text2.setText(CountriesList.mrn[position]);
        holder.text3.setText(CountriesList.actualstart[position]);
        holder.text4.setText(CountriesList.age[position]);
        holder.text5.setText(CountriesList.gender[position]);
        holder.text6.setText(CountriesList.wardNo[position]);
        holder.text7.setText(CountriesList.roomNo[position]);
        holder.text8.setText(CountriesList.bedNo[position]);

        return convertView;
    }


    static class ViewHolder {
        public Button btnList;
        public TextView text8;
        public TextView text7;
        public TextView text6;
        public TextView text5;
        public TextView text4;
        public TextView text1;
        public TextView text2;
        public TextView text3;
    }

    @Override
    public void notifyDataSetChanged() // Create this function in your adapter class
    {
        super.notifyDataSetChanged();
    }


}



}

Answer 1

Add new values in your adapter and call notifyDataSetChanged .

Follow the step to update listview.

1) First Add new values to your CountriesList .
2) Before Assign EfficientAdapter to listiew, make one object of it and then assign that object.
3) Create one function in your  EfficientAdapter class called notifyDataSetChanged().
4) Call notifyDataSetChanged() function using EfficientAdapter object.

Example

EfficientAdapter objectAdapter = new EfficientAdapter(this);
listView.setAdapter(objectAdapter);

@Override
public void notifyDataSetChanged() // Create this function in your adapter class
{
    super.notifyDataSetChanged();
}

Now call objectAdapter.notifyDataSetChanged() on onClick event of refresh button.