Android creating AlertDialog using values from ArrayList?

Question

I am using following code to create a Dialog aleart box with lists item from studentNames ArrayList.I am creating this ArrayList by reading childfile array.But when this code runs it just display a Dialog box with zero list item.I have even check my studentNames for null but it has values in it.According to documentation I need to set ListAdapter for showing list items in Dialog box , but that's also not working for me.Please help me finding the problem.

ArrayList<String> studentNames  = new ArrayList<String>();
            for (File file2 : childfile) {
                studentNames.add(file2.getName());
            }

    AlertDialog.Builder builder = new AlertDialog.Builder(context);
            builder.setTitle(student.getName()).setAdapter(new ArrayAdapter(context, android.R.layout.simple_list_item_1, studentNames),
                    new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int which) {

                            switch (which) {

                               cases
                            }

                        }
                    });
            builder.create();
            builder.show();

Answer 1

This is how you can achieve it:

final CharSequence[] items = {"1", "2", "3"};

AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Select");
builder.setItems(items, new DialogInterface.OnClickListener() {
    public void onClick(DialogInterface dialog, int item) {
        // Do something with the selection
        dialog.dismiss();
    }
});
builder.show();