ListView OnItemClickListner

Yes, in this article we did two things,

1. Adding Items to ListView
2. Register ListView to event(OnItemClickListner) to find which item is clicked.

Adding Items to ListView

In Add(onclick) adding items to Listview at runtime using ArrayList, ArrayAdapter of string type.

ArrayAdapter will take String[] as a parameter as a source. so i taken arraylist(al). arraylist can take string item.

String item=edt.getText().toString().trim();
al.add(item); then adapter will be updated automatically using predefined event

adapter.notifyDataSetChanged();   at onCreate method it taken al as input/source.

adapter=new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1,al);

Register OnItemClickListener

import android.widget.AdapterView.OnItemClickListener;

MainActivity implement OnItemClickListerner also. which fires whenever an item is clicked on ListView.

this event has 4 parameters.

onItemClick(AdapterView<?> parent, View view, int position,long id);

parent  :  is Listview,Gridview,spinner,...ect who currently binding Adapterview data.

as well we can check (Listview1, Listview2..also)

view :   view with in the AdapterView.  

position :  item position in the adapterview.

args3   : the Row id of the item was clicked.

ListView Databinding, add remove items

yes, we know Listview a component to bind list of items, if items are more it will show items in scrollview behaviour.

in this demo: we added 2 string-array files(awords,bwords). awords added at design time, and bwords are added at runtime(button click--Bind items).

blistwords items are,we can't get at class declaration time because bwords are not available resources are loaded. so added that onclick event.

public class MainActivity extends Activity implements OnClickListener,OnItemClickListener
{
    Button addbtn,delbtn;
    ListView listview;
    EditText edt;
    ArrayList<String> al;
    ArrayAdapter<String> arrayadapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
edt=(EditText)findViewById(R.id.editText1);
listview=(ListView)findViewById(R.id.listView1);
addbtn=(Button)findViewById(R.id.button1);
delbtn=(Button)findViewById(R.id.button2);
al=new ArrayList<String>();
arrayadapter=new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1,al);
listview.setAdapter(arrayadapter);
addbtn.setOnClickListener(this);
delbtn.setOnClickListener(this);
listview.setOnItemClickListener(this);
}
Add and remove items

public void onClick(View v)
{
if(v==addbtn)
{
String item=edt.getText().toString().trim();
if(item.length()>0)
{
al.add(item);
arrayadapter.notifyDataSetChanged();
edt.setText("");
edt.requestFocus();
}
}
if(v==delbtn)
{
String item=edt.getText().toString().trim();
if(item.length()>0)
{
al.remove(item);
arrayadapter.notifyDataSetChanged();
edt.setText("");
edt.requestFocus();
}
}
}

AdapterView event : this event supports of listview, spinner...ect

public void onItemClick(AdapterView<?> parent, View view, int position,long id)

{

TextView tv=(TextView)view;

String item=tv.getText().toString();

edt.setText(item);

}