How to remove listview all items

Question

In my app, if you click on a button then i want to remove all the listview items. Here, i am using the base adapter for adding the items to the list view.

How can i remove the listview items dynamically.

Answer 1

Call setListAdapter() again. This time with an empty ArrayList.

Answer 2

ListView operates based on the underlying data in the Adapter. In order to clear the ListView you need to do two things:

1. Clear the data that you set from adapter.
2. Refresh the view by calling notifyDataSetChanged

For example, see the skeleton of SampleAdapter below that extends the BaseAdapter

public class SampleAdapter extends BaseAdapter {

    ArrayList<String> data;

    public SampleAdapter() {
        this.data = new ArrayList<String>();
    }

    public int getCount() {
        return data.size();
    }

    public Object getItem(int position) {
        return data.get(position);
    }

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

    public View getView(int position, View convertView, ViewGroup parent) {
        // your View
        return null;
    }
}

Here you have the ArrayList<String> data as the data for your Adapter. While you might not necessary use ArrayList, you will have something similar in your code to represent the data in your ListView

Next you provide a method to clear this data, the implementation of this method is to clear the underlying data structure

public void clearData() {
    // clear the data
    data.clear();
}

If you are using any subclass of Collection, they will have clear() method that you could use as above.

Once you have this method, you want to call clearData and notifyDataSetChanged on your onClick thus the code for onClick will look something like:

// listView is your instance of your ListView
SampleAdapter sampleAdapter = (SampleAdapter)listView.getAdapter();
sampleAdapter.clearData();

// refresh the View
sampleAdapter.notifyDataSetChanged();

Answer 3

if you used List object and passed to the adapter you can remove the value from the List object and than call the notifyDataSetChanged() using adapter object.

for e.g.

List<String> list = new ArrayList<String>();
ArrayAdapter adapter;


adapter = new ArrayAdapter<String>(DeleteManyTask.this, 
            android.R.layout.simple_list_item_1,
            (String[])list.toArray(new String[0]));

listview = (ListView) findViewById(R.id.list);
listview.setAdapter(adapter);

listview.setAdapter(listAdapter);

for remove do this way

list.remove(index); //or
list.clear();
adpater.notifyDataSetChanged();

or without list object remove item from list.

adapter.clear();
adpater.notifyDataSetChanged();

Answer 4

You can only use

 lv.setAdapter(null);

Answer 5

You can do this:

listView.setAdapter(null);