Android可点击列表视图崩溃

Question

我正在尝试让Listview变为可点击，但如果有任何方法/函数被调用，它会立即崩溃，如toast（）;

    listAdapter = new ArrayAdapter<String>(this, R.layout.simplerow, arrayListCarros);  
    mainListView.setAdapter( listAdapter );      
    db.close();



    mainListView.setClickable(true);
    mainListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        public void onItemClick(AdapterView<?> arg0, View arg1, int position, long arg3) {
            toast(position);

      }
    }); 

Answer 1

 mainListView.setClickable(true);
    mainListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        public void onItemClick(AdapterView<?> arg0, View arg1, int position, long arg3) {
            Toast.makeText(activityname.this, String.valueOf(position), Toast.LENGTH_SHORT).show();

            Intent intent = new intent(activityName.this,targerActivity.class);
            activityName.this.startActivity(intent);    
  }