How to delete a specific Listview item?

Question

I would like to ask a question: I have one ListView, in which his Adapter is clarified in the same Activity and the content of Adapter (as strings) are in another class, in another package. How do I delete a specific item from ListView, same code, no user interaction? (for example, an application update where an item will no longer appear).

In the case I am studying, the user will click on an item from listView, and a string inside Activity will be filled with the string in otherClass.lista and depending on the position (position) clicked, a different text will appear.

EDITED

Follow the Listview click action:

ListView listView = (ListView) findViewById(R.id.lista);
listView.setAdapter(new listAdapter(this));

listView.setOnItemClickListener(new OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> arg0, View arg1,
                int position, long arg3) {

                nome.setText(otherClass.string.get(position));

            }
});

Follow the Adapter I’m using:

public class listAdapter extends BaseAdapter implements ListAdapter {

    public Context context;
    public ArrayList<String> lug;
    public Typeface fonte;

    public listAdapter(Context context) {



        lug = otherClass.string;


        this.context = context;
    }

    @Override
    public int getCount() {
        return lug.size();
    }

    @Override
    public Object getItem(int position) {
        return lug[position];
    }

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

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {

            TextView title = new TextView(context);     
            title.setText(lug.get(position));
            title.setTextSize(18);

        return title;
    }

}

Now follow the Array in the class that is in another package

public class otherClass {

public static ArrayList<String> string = new ArrayList<String>();{
    string.add("primeiro item");
    string.add("Segundo item");
}
} 

The current problem is that the Arraylist items above are not being printed... and I would like to know (when to print the items) how to delete the items.

The intention, as follows the images, would be that in the otherClass have the items that will appear on listView and clicking on some item will appear the respective information of the clicked item (these declared in the same class not to get confused all separate). More items will be added to each app update, so it needs to be a dynamic and organized mode. Ideas? (since Strings doesn’t seem like a good shape)

Answer 1

Come on @GH_ see if this helps.

Create a class called Others, this class will persist the data you want for a particular object, let’s assume it is a person, car, or anything. In your case will persist two Strings: first item and second item.

/**
 * Classe que irá persistir dados de um objeto para ser usado em uma lista de Strings.
 */
public class Outros {
    private String primeiroItem;
    private String segundoItem;

    public Outros( String primeiroItem, String segundoItem ) {
        this.primeiroItem = primeiroItem;
        this.segundoItem = segundoItem;
    }

    public String getPrimeiroItem() {
        return primeiroItem;
    }

    public void setPrimeiroItem( String primeiroItem ) {
        this.primeiroItem = primeiroItem;
    }

    public String getSegundoItem() {
        return segundoItem;
    }

    public void setSegundoItem( String segundoItem ) {
        this.segundoItem = segundoItem;
    }
}

Your Adapter can take the next shape:

public class MeuCustomAdapter extends BaseAdapter {
    /** Lista de objetos outros, contendo duas Strings. */
    private List<Outros> listOutros;
    /** Contexto usado para acessar recursos de string */
    private Context contexto;

    /**
     * Metodo construtor que recebe o contexto e uma lista de objetos instrumentos para popular o ListView personalizado.
     *
     * @param contexto Contexto uasdo para acessar o recurso de layout.
     * @param listOutros  Lista de objetos da representacao de cada item de lista (linha do ListView).
     */
    public MeuCustomAdapter( Context contexto, List<Outros> listOutros ) {
        this.contexto = contexto;
        this.listOutros = listOutros;
    }

    @Override
    public int getCount() {
        return listOutros.size();
    }

    @Override
    public Object getItem( int position ) {
        return listOutros.get( position );
    }

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

    /**
     * Chamado toda vez que e necessario mostrar um item da ListView.
     *
     * @param position    A posicao do item de ListView.
     * @param convertView O elemento View que representa o item de ListView.
     * @param parent      Elemento pai do elemento view.
     */
    @Override
    public View getView( int position, View convertView, ViewGroup parent ) {
        TextView textViewTitle = new TextView( contexto );
        // Aqui é definido como texto do TextView o primeiro item do objeto Outros.
        textViewTitle.setText( listOutros.get( position ).getPrimeiroItem() );
        textViewTitle.setTextSize(18);

        // Para exibir o item você tem que retornar uma VIEW e não uma String.
        return textViewTitle;
    }
}

In Your Love you do so:

    ListView listView = findViewById( R.id.meuListView );

    Outros outros1 = new Outros( "Outros 1", "Item 1" );
    Outros outros2 = new Outros( "Outros 2", "Item 2" );
    Outros outros3 = new Outros( "Outros 3", "Item 3" );

    List<Outros> listOutros = new ArrayList<Outros>();
    listOutros.add( outros1 );
    listOutros.add( outros2 );
    listOutros.add( outros3 );

    MeuCustomAdapter meuCustomAdapter = new MeuCustomAdapter( getAplicationContext(), listOutros );
    listView.setAdapter( meuCustomAdapter );

I do not know if it will help, you have to give an extra study in Lists, Adapters, Viewholder pattern...

---

EDICT : And to delete a specific Listview item just do so:

To remove an item from an Arraylist you have the following options:

1. seuArrayList.clear() - Removes all elements of the array leaving it empty;
2. seuArrayList.remove(index) - Removes the object at the position specified in the list;
3. seuArrayList.remove(Object) - Removes the instance of the specified object if it is contained.

Answer 2

You can use adapter.remove() and then call the method notifyDataSetChanged() to have the changes reflected in the Listview.

Behold:

adapter.remove(adapter.getItem(index)); // Índice do item a ser deletado
adapter.notifyDataSetChanged();