我的viewpager中有8个具有相同布局的片段。该片段包含回收器视图和文本视图。我的问题是，当我启动viewpager片段时，所有数据都会加载到第一个片段本身上，并且其余的片段中都没有显示任何内容。以下是我在片段中设置适配器和viewpager的方法。
adapter = new SelectPlayerAdapter(getActivity(), getChildFragmentManager());
//Set up the view pager.
setupViewPager(pager);
private void setupViewPager(ViewPager viewPager) {
adapter.addFragment(new PlayersFragment(), "BATSMAN 1", batsman_1);
adapter.addFragment(new PlayersFragment(), "BATSMAN 2", batsman_2);
adapter.addFragment(new PlayersFragment(), "BATSMAN 3", batsman_3);
adapter.addFragment(new PlayersFragment(), "ALL-ROUNDER 1", all_rounder_1);
adapter.addFragment(new PlayersFragment(), "ALL-ROUNDER 2", all_rounder_2);
adapter.addFragment(new PlayersFragment(), "WICKET-KEEPER", wicket_keeper);
adapter.addFragment(new PlayersFragment(), "BOWLER 1", bowler_1);
adapter.addFragment(new PlayersFragment(), "BOWLER 2", bowler_2);
viewPager.setAdapter(adapter);
}
这是我的Adapter类。
public class SelectPlayerAdapter extends FragmentStatePagerAdapter {
Context context = null;
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
private final ArrayList<String> player_list = new ArrayList<>();
Gson gson;
public SelectPlayerAdapter(Context context, android.support.v4.app.FragmentManager mgr) {
super(mgr);
this.context = context;
}
@Override
public int getCount() {
return mFragmentList.size();
}
@Override
public android.support.v4.app.Fragment getItem(int position) {
Fragment player_fragment = mFragmentList.get(position);
Bundle bundle = new Bundle();
bundle.putString("player_position_string", player_list.get(position));
player_fragment.setArguments(bundle);
return player_fragment;
}
public void addFragment(android.support.v4.app.Fragment fragment, String title, ArrayList<Player> players_position_list) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
gson = new Gson();
String players_position_string = gson.toJson(players_position_list);
player_list.add(players_position_string);
}
@Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
我在添加片段并将它们添加到我的适配器中的不同arraylist时传递不同的arraylists，当调用get item时我从arraylist获取项目并将其作为参数传递给该片段但是当我运行它时，我最初只获取所有参数，当我更改选项卡时没有任何反应。我试过调试，看到getitem最初只调用8次，当我更改viewpager选项卡时没有任何反应。我已尝试过片段newinstance方法和addonpagechangelistener，但得到了相同的结果。请帮忙。
这是我的Players Fragment课程。
public class PlayersFragment extends Fragment {
private TextView player_position_text;
private TextView player_position_number_text;
private RecyclerView players_list_view;
Bundle extra;
private String players_string;
private ArrayList<Player> player_position_list;
Gson gson;
public PlayersFragment() {
// Required empty public constructor
}
public static Fragment newInstance(Context context) {
PlayersFragment playersFragment = new PlayersFragment();
return playersFragment;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.select_player_layout, container, false);
//Get the bundle from previous fragment.
extra = this.getArguments();
//If bundle contains the key players string then retrieve it.
if(extra.containsKey("player_position_string")){
players_string = extra.getString("player_position_string", "0");
System.out.println("players string is " + players_string);
gson = new Gson();
Type type = new TypeToken<List<Player>>() {
}.getType();
player_position_list = gson.fromJson(players_string, type);
System.out.println("players list is " + player_position_list);
System.out.println("players name is " + player_position_list.get(1).getName());
}
//If bundle does not contain string it then display a toast.
else
{
// Display toast with exception.
Toast.makeText(getActivity(), "There was some error with getting the details. Please try again later.",
Toast.LENGTH_LONG).show();
}
player_position_text = view.findViewById(R.id.player_position_text);
player_position_number_text = view.findViewById(R.id.player_position_number_text);
players_list_view = view.findViewById(R.id.players_list_view);
return view;
}
答案 0 :(得分：0)
编辑：
我添加了一个工作演示。请您检查一下，如果有效，请告诉我。
Player.java
public class Player implements Parcelable {
private String name;
private int age;
public Player(String name, int age) {
this.name = name;
this.age = age;
}
public String getName() {
return name;
}
public int getAge() {
return age;
}
protected Player(Parcel in) {
name = in.readString();
age = in.readInt();
}
public static final Creator<Player> CREATOR = new Creator<Player>() {
@Override
public Player createFromParcel(Parcel in) {
return new Player(in);
}
@Override
public Player[] newArray(int size) {
return new Player[size];
}
};
@Override
public int describeContents() {
return 0;
}
@Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeString(name);
dest.writeInt(age);
}
@Override
public String toString() {
return "Player{" +
"name='" + name + '\'' +
", age=" + age +
'}';
}
}
PlayerFragment.java
public class PlayerFragment extends Fragment {
private static final String ARG_PLAYERS = "arg_player";
private Player player;
public static PlayerFragment newInstance(Player players) {
Bundle args = new Bundle();
args.putParcelable(ARG_PLAYERS, players);
PlayerFragment fragment = new PlayerFragment();
fragment.setArguments(args);
return fragment;
}
public PlayerFragment() {
// Required empty public constructor
}
@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Bundle args = getArguments();
if (args != null){
this.player = args.getParcelable(ARG_PLAYERS);
}
if (player == null){
throw new IllegalArgumentException("Player list can not be null");
}
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_player, container, false);
}
@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
((TextView)view.findViewById(R.id.txt_player)).setText(player.toString());
}
}
StatePagerAdapter.java
public class StatePagerAdapter extends FragmentStatePagerAdapter {
private ArrayList<Player> players;
private List<String> titles;
public StatePagerAdapter(FragmentManager fm, ArrayList<Player> players, List<String> titles) {
super(fm);
if (players.size() != titles.size())
throw new IllegalArgumentException("Sizes must be equal");
this.players = players;
this.titles = titles;
}
@Override
public Fragment getItem(int position) {
return PlayerFragment.newInstance(players.get(position));
}
@Override
public int getCount() {
return players.size();
}
@Override
public CharSequence getPageTitle(int position) {
return titles.get(position);
}
}
MainActivity.java
public class MainActivity extends AppCompatActivity {
ViewPager viewPager;
@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ArrayList<Player> players = new ArrayList<>();
players.add(new Player("a", 1));
players.add(new Player("b", 2));
players.add(new Player("c", 3));
List<String> titles = new ArrayList<>(Arrays.asList("Title1", "Title2", "Title3"));
StatePagerAdapter adapter = new StatePagerAdapter(getSupportFragmentManager(), players, titles);
viewPager = findViewById(R.id.view_pager);
viewPager.setAdapter(adapter);
}
}
上一篇：
您能否请分享您的PlayersFragment课程并尝试以下代码。
@Override
public android.support.v4.app.Fragment getItem(int position) {
Fragment player_fragment = new PlayerFragment();
Bundle bundle = new Bundle();
bundle.putString("player_position_string", player_list.get(position));
player_fragment.setArguments(bundle);
return player_fragment;
}