Adding ListView Sub Item Text in Android

Question

I have created an RSS reader that lists items in a listview. I also want a date below each item, but I have no idea how to do that. I need someone\'s help to make the Sub

Answer 1

The simplest solution is probably to substitute the ArrayAdapter and the android.R.layout.simple_list_item_1 that you are using with a SimpleAdapter and the android.R.layout.simple_list_item_2 predefined layout. This layout is composed by two TextViews, with an id of android.R.id.text1 (the "item") and android.R.id.text2 (the "sub item") respectively, which you will need as a reference for the SimpleAdapter to work.

By looking at the constructor for SimpleAdapter you will notice that, apart from a Context instance and the id of a layout resource, it takes three parameters that may be new to you:

• a List> instance where you put the elements you want the ListView to show. Elements are in the form of a Map, i.e. something akin to a struct composed by properties in form of name/value pairs. For example, you may use "title" and "date" as keys for the title and date of each RSS item, respectively.
• an array of strings, where to put the names of the keys in each map that you want to show on the ListView.
• an array of integers where you need to put the ids of the parts in the list item view where you want the single elements referenced by the keys in the preceding array of strings to be shown. For example, if you want to show the title and date of a RSS item in the "item" and "sub item" views respectively, you use new String[] { "title", "date" } as the array of strings argument, and new int[] { android.R.id.text1, android.R.id.text2 } as this argument.

A rough code example, just to give you the idea:

List> data = new ArrayList>();
for (RSSItem item : feed.getAllItems()) {
    Map datum = new HashMap(2);
    datum.put("title", item.getTitle());
    datum.put("date", item.getDate().toString());
    data.add(datum);
}
SimpleAdapter adapter = new SimpleAdapter(this, data,
                                          android.R.layout.simple_list_item_2,
                                          new String[] {"title", "date"},
                                          new int[] {android.R.id.text1,
                                                     android.R.id.text2});
itemList.setAdapter(adapter);

The documentation states that "the maps contain the data for each row, and should include all the entries specified in the from parameter", so both title and date should always be present.

Please note that this is all off the top of my head. I haven't actually tested all the code, so you may very well encounter some quirk or bug that you need to adjust or fix on your way up.