1 /* 2 * Copyright (C) 2012 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package com.example.android.fragments; 17 18 import android.app.Activity; 19 import android.os.Bundle; 20 import android.support.v4.app.ListFragment; 21 import android.view.View; 22 import android.widget.ArrayAdapter; 23 import android.widget.ListView; 24 25 public class HeadlinesFragment extends ListFragment { 26 OnHeadlineSelectedListener mCallback; 27 28 // The container Activity must implement this interface so the frag can deliver messages 29 public interface OnHeadlineSelectedListener { 30 /** Called by HeadlinesFragment when a list item is selected */ onArticleSelected(int position)31 public void onArticleSelected(int position); 32 } 33 34 @Override onCreate(Bundle savedInstanceState)35 public void onCreate(Bundle savedInstanceState) { 36 super.onCreate(savedInstanceState); 37 38 // We need to use a different list item layout for devices older than Honeycomb 39 int layout = Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB ? 40 android.R.layout.simple_list_item_activated_1 : android.R.layout.simple_list_item_1; 41 42 // Create an array adapter for the list view, using the Ipsum headlines array 43 setListAdapter(new ArrayAdapter<String>(getActivity(), layout, Ipsum.Headlines)); 44 } 45 46 @Override onStart()47 public void onStart() { 48 super.onStart(); 49 50 // When in two-pane layout, set the listview to highlight the selected list item 51 // (We do this during onStart because at the point the listview is available.) 52 if (getFragmentManager().findFragmentById(R.id.article_fragment) != null) { 53 getListView().setChoiceMode(ListView.CHOICE_MODE_SINGLE); 54 } 55 } 56 57 @Override onAttach(Activity activity)58 public void onAttach(Activity activity) { 59 super.onAttach(activity); 60 61 // This makes sure that the container activity has implemented 62 // the callback interface. If not, it throws an exception. 63 try { 64 mCallback = (OnHeadlineSelectedListener) activity; 65 } catch (ClassCastException e) { 66 throw new ClassCastException(activity.toString() 67 + " must implement OnHeadlineSelectedListener"); 68 } 69 } 70 71 @Override onListItemClick(ListView l, View v, int position, long id)72 public void onListItemClick(ListView l, View v, int position, long id) { 73 // Notify the parent activity of selected item 74 mCallback.onArticleSelected(position); 75 76 // Set the item as checked to be highlighted when in two-pane layout 77 getListView().setItemChecked(position, true); 78 } 79 }