单击列表视图项后如何更改文本视图中的文本？

Question

I am new to android programming. For my android app what I want to do is when a user clicks on an item in listView, a new page is opened with a title of the item's text. here is my code:

protected void onListItemClick(ListView l, View v, int position, long id) {
    String item = (String) getListAdapter().getItem(position);
    TextView tv = (TextView)findViewById(R.id.TextView1);
    tv.setText("Some new text");
    Intent intent = new Intent(TypeListActivity.this, List_vaccine_info.class );
    startActivity(intent);
    //Toast.makeText(this, item + " selected", Toast.LENGTH_LONG).show();
}

but it won't run. when I remove:

TextView tv = (TextView)findViewById(R.id.TextView1);
    tv.setText("Some new text");

it works but this isn't what I want, I want to change the title based on the item's text in listView that the user clicked any help would be appreciated

Answer 1

If you are using some default layout for each item in the textview (and a default ArrayAdapter), you need to change the string that is in the ArrayList that the ArrayAdapter is using.

If you are using a custom layout, you still need to do the above and have your getView() method get the TextView in that item and set its text.

Answer 2

You have to implement onItemClick to get clicked item:

   public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
                long arg3) {
         String text = ArrayList.get[arg2];  //where arg2 is position where you had click and ArrayList is List with which you have initialized your Listview 

          Intent i=new Intent(this,NextActivity.class);
          i.putExtra("Text",text);            
          startActivity(i);

    }

In Next Screen,use this code in onCreate() method:

      Bundle extras = getIntent().getExtras();
      String title=extras.getString("Text");
      setTitle(title);