public class HomeFragment extends Fragment {
private ListView listView;
private DatabaseHelper databaseHelper;
private SQLiteDatabase db;
public class HomeFragment extends Fragment {
private ListView listView;
private TextView text_home;
private DatabaseHelper databaseHelper;
private SQLiteDatabase db;
private ArrayList<Books> listData;
private BookAdapter bookAdapter;
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View root = inflater.inflate(R.layout.fragment_home, container, false);
return root;
}
@Override
public void onActivityCreated(@Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
databaseHelper = new DatabaseHelper(getContext());
listView = (ListView) getActivity().findViewById(R.id.home_list);
db = databaseHelper.getWritableDatabase();
Cursor c = db.query("books", new String[]{"_id", "book_id", "book_name", "book_author", "book_type", "book_pub", "book_num"}, null, null, null, null, null);
if (c.getCount() > 0) {
SimpleCursorAdapter adapter = new SimpleCursorAdapter(getContext(), R.layout.book_list, c,
new String[]{"_id", "book_id", "book_name", "book_author", "book_type", "book_pub", "book_num"},
new int[]{R.id.id, R.id.book_id, R.id.book_name, R.id.book_author, R.id.book_type, R.id.book_pub, R.id.book_num});
this.listView.setAdapter(bookAdapter);
this.registerForContextMenu(listView);
Toast.makeText(getContext(),"查询成功",Toast.LENGTH_SHORT).show();
}else {
Toast.makeText(getContext(),"网络不佳，获取信息失败",Toast.LENGTH_SHORT).show();
}
}
}
“查询成功”，都能显示出来，就是显示不出来结果
