Question

I use Objects (beans) that we’ll call Category.
These Category objects contain a set of attributes including a list of Category objects.

public class Category {
     private List<Category> categoryList;
     ...
     private Strings anAttribute;
}

At compilation, I do not know the depth of the root Category object, meaning : how many Category are in the list of the root Category and how many Category objects are in each one of the list and so go on. I actually get the root Category object by parsing an XML file.

I have an activity, which, to resume, shows a set of buttons. Each button represents a root Category object (each from an XML file). I would like that once I click on one of these buttons, I get a new “window” showing a set of buttons (a button per Category in the List) and each of this button shows recursively a new “window” showing a set of buttons…

How could I do that knowing I’d like to use XML files for the contents I want to display ? I guess the point is not to create an activity per Category (even dynamically).

Thank you for your help.

Answer 1

You could use the following structure:

private LinearLayout myLayout;

protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.something);

    myLayout = (LinearLayout) findViewById(R.id.my_layout);
    createBtns( loadFirstCategory() );
}

private void createBtns(Category c)
{
    List<Category> c_list = c.getCategoryList();
    for (int i=0; i<c_list.size(); i++)
    {
        Button btn = new Button(this);
        btn.setText( c_list.get(i).getName() );
        myLayout.addView(btn);

        btn.setOnClickListener(new OnClickListener() {
            public void onClick()
            {
                myLayout.removeAll();
                createBtns( c_list.get(i) );
            }
        });
    }
}