java - Android ListView selected item stay highlighted

Question

I have an XML with two ListView, one with a list of clients filled by a select query (lv_cli) and the other with the details of the client selected (lv_cli_det). I would like to keep the client selected in the lv_cli while the lv_cli_det show the details.

XML:

<ListView
    android:id="@+id/cli_lista"
    android:layout_width="512dp"
    android:layout_height="wrap_content"
    android:fadeScrollbars="false"
    >
</ListView>

<ListView
    android:id="@+id/cli_lista_det"
    android:layout_width="512dp"
    android:layout_height="wrap_content"
    android:layout_toRightOf="@+id/cli_lista"
    android:fadeScrollbars="false" >
</ListView>

Java:

Cursor cursor = db.rawQuery("Select NrCl||';'||Nome From Clientes", null);
final ListView t = (ListView)findViewById(R.id.cli_lista);
ArrayAdapter<String> myarrayAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_expandable_list_item_1, listItems);
t.setAdapter(myarrayAdapter);

final ListView td = (ListView)findViewById(R.id.cli_lista_detalhe);
final ArrayAdapter<String> myarrayAdapter2 = new ArrayAdapter<String>(this, android.R.layout.simple_expandable_list_item_1, listItems2);

t.setOnItemClickListener(new OnItemClickListener() {
    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
        String item = ((TextView)view).getText().toString();
        String[] strArray = item.split("\;");

        cli.load(strArray[0].toString());
        td.setAdapter(myarrayAdapter2);
        listItems2.clear();
        listItems2.add("Nome: " + cli.getNome());
        listItems2.add("Morada: " + cli.getMorada());
        listItems2.add("Localidade: " + cli.getLoca());
        listItems2.add("Código Postal: " + cli.getCp());
        listItems2.add("Pais: " + cli.getPais());
        listItems2.add("Nif: " + cli.getNif());
        listItems2.add("Tel: " + cli.getTel());
        listItems2.add("Tlm: " + cli.getTlm());
        listItems2.add("Tipo Pre?o: " + cli.getTipoPvn());
        listItems2.add("Cond. Pagamento: " + cli.getCpg());
        listItems2.add("Obs: " + cli.getObs());
        td.setAdapter(myarrayAdapter2);
        myarrayAdapter2.notifyDataSetChanged(); 
    }
});

Answer 1

I found the proper way. It's very simple. In resource describe following:

android:choiceMode="singleChoice"
android:listSelector="#666666"

(or you may specify a resource link instead of color value)

Programmatical:

listView.setSelector(Drawable selector);
listView.setSelector(int resourceId);
listView.setChoiceMode(int mode);

mode can be one of these: AbsListView.CHOICE_MODE_SINGLE, AbsListView.CHOICE_MODE_MULTIPLE, AbsListView.CHOICE_MODE_NONE (default)

(AbsListView is the abstract ancestor for the ListView class)

P.S. manipulations with onItemClick and changing view background are bankrupt, because a view itself is a temporary object. Hence you must not to track a view.

If our list is long enough, the views associated with scrolled out items will be removed from hierarchy, and will be recreated when those items will shown again (with cached display options, such as background). So, the view we have tracked is now not an actual view of the item, and changing its background does nothing to the actual item view. As a result we have multiple items selected.