Question

I’m pretty new to Android dev and still working out a lot of things.

I’ve got a main menu showing using the following code, but can’t work out how to disable selected items in the menu. Can anybody help me with some sample code?

public class listTest extends ListActivity {

    @Override
    public void onCreate(Bundle savedState) {
        super.onCreate(savedState);
        setListAdapter(ArrayAdapter.createFromResource(this, R.array.mainMenu,
                android.R.layout.simple_list_item_1)); 
        //not sure how to disable list items here
    }

    protected void onListItemClick(ListView list, View view, int position, long id) {
        // can disable items when they are clicked on
        view.setEnabled(false);
    }   

}

and I have a string-array in my strings.xml file:

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string-array name="mainMenu">
        <item>Item 1</item>
        <item>Item 2</item>
        <item>Item 3</item>
    </string-array> 
</resources>

Thank you

Answer 1

In order to disable list items on list creation you have to subclass from ArrayAdapter. You have to override the following methods: isEnabled(int position) and areAllItemsEnabled(). In former you return true or false depending is list item at given position enabled or not. In latter you return false.

If you want to use createFromResource() you will have to implement that method as well, since the ArrayAdapter.createFromResource() still instantiates ArrayAdapter instead of your own adapter.

Finally, the code would look something like the following:

class MenuAdapter extends ArrayAdapter<CharSequence> {

    public MenuAdapter(
            Context context, int textViewResId, CharSequence[] strings) {
        super(context, textViewResId, strings);
    }

    public static MenuAdapter createFromResource(
            Context context, int textArrayResId, int textViewResId) {

        Resources      resources = context.getResources();
        CharSequence[] strings   = resources.getTextArray(textArrayResId);

        return new MenuAdapter(context, textViewResId, strings);
    }

    public boolean areAllItemsEnabled() {
        return false;
    }

    public boolean isEnabled(int position) {
        // return false if position == position you want to disable
    }
}