android - Delete item by clicking any item in listview

Question

I made a listview where at the header an edit text field to add list.And it works fine and successfully add item. Then I try to call this listview and set the adapter. Now what I want is when I click the item it should be deleted, but its getting force closed. Here is my code:

public class AddDeleteItemActivity extends ListActivity {
public ListView listViewCity;
public Context ctx;

ArrayList list = new ArrayList();

ArrayAdapter adapter;

@Override
public void onCreate(Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);

   setContentView(R.layout.main);

   Button btn = (Button) findViewById(R.id.btnAdd);
   ctx=this;


   adapter = new ArrayAdapter(this, android.R.layout.simple_list_item_multiple_choice, list);

   OnClickListener listener = new OnClickListener() {
       @Override
       public void onClick(View v) {
           EditText edit = (EditText) findViewById(R.id.txtItem);
           list.add(edit.getText().toString());
           edit.setText("");
           adapter.notifyDataSetChanged();
       }
   };


   listViewCity = ( ListView ) findViewById( R.id.list);
   listViewCity.setAdapter(adapter);

   listViewCity.setOnItemClickListener(new OnItemClickListener() {
       @Override
       public void onItemClick(AdapterView<?> a, View v, int position, long id) { 

               Toast.makeText(getApplicationContext(), " " +position , Toast.LENGTH_LONG).show();
               SparseBooleanArray checkedItemPositions = getListView().getCheckedItemPositions();
               int itemCount = getListView().getCount();

               for(int i=itemCount-1; i >= 0; i--){
                   if(checkedItemPositions.get(i)){
                       adapter.remove(list.get(i));
                   }
               }
               adapter.notifyDataSetChanged();
       }

   });


   btn.setOnClickListener(listener);

   setListAdapter(adapter);
}
}

Answer 1

试试这个方法

listViewCity.setOnItemClickListener(new OnItemClickListener() {
       @Override
       public void onItemClick(AdapterView<?> a, View v, int position, long id) { 

               Toast.makeText(getApplicationContext(), " " +position , Toast.LENGTH_LONG).show();
               list.remove(position);
               adapter.notifyDataSetChanged();
               adapter.notifyDataSetInvalidated();
       }

   });

从列表中删除并使用适配器通知刷新您的列表

已编辑

为什么在扩展 ListActivity 时使用此语句

listViewCity = ( ListView ) findViewById( R.id.list);

您可以使用 getListView() 扩展 ListActivity 或扩展 Activity 而不是 ListActivity 来获取 ListView 对象。