Question

我有一个带有listFragments的应用程序，我希望以更好的方式将Realm中的数据显示在它们中。例如，我有拥有大量数据的用户（姓名，喜欢的体育等...）

用户类：

public class User extends RealmObject {
@PrimaryKey
private long id;
private String firstName;
private String lastName;
private String email;
private RealmList<UserSport> sports = new RealmList<>();
private RealmList<User> friends= new RealmList<>();
private RealmList<User> sportmates= new RealmList<>();
{and some other, and getters and setters} 
}

用户可以选择“用户”菜单，其中有3个ListFragments在不同的标签中（朋友，运动员，其他）

朋友片段：

public class FriendsFragment extends ListFragment {
List<User> users;
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup    container, @Nullable Bundle savedInstanceState) {
    View v = inflater.inflate(R.layout.my_team, container, false);
    users=new ArrayList<>();           
        long userid=/*The currently logged in users id.*/
        Realm realm = Realm.getInstance(getContext());
        users.addAll(realm.where(User.class).equalTo("id",userid).findFirst().getFriends());
    MySportmateListAdapter adapter = new   MySportmateListAdapter(getContext(), users);
    setListAdapter(adapter);
    return v;
}

@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);

    final ListView listView = getListView();
    final SwipeRefreshLayout swipeRefreshLayout = (SwipeRefreshLayout) view.findViewById(R.id.swipe_refresh_layout);
    // swipeRefreshLayout.setOnRefreshListener();
    swipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
        //TODO implement
    });
    listView.setOnScrollListener(new AbsListView.OnScrollListener() {
        @Override
        public void onScrollStateChanged(AbsListView view, int scrollState) {

        }

        @Override
        public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
            int topRowVerticalPosition = (listView == null || listView.getChildCount() == 0) ? 0 : listView.getChildAt(0).getTop();
            swipeRefreshLayout.setEnabled(firstVisibleItem == 0 && topRowVerticalPosition >= 0);
        }

    });
}

@Override
public void onListItemClick(ListView l, View v, int position, long id) {
    super.onListItemClick(l, v, position, id);
    Toast.makeText(getContext(), "Here is " + position + ". item " + v.getTag(), Toast.LENGTH_LONG).show();

}

MyListAdapter从baseadapter扩展（并实现可过滤，但它用于其他用途，因此现在不需要）：

package teammeup.com.teammeup.ListAdapters;

import android.content.Context;
import android.graphics.drawable.Drawable;
import android.support.v4.app.ListFragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Filter;
import android.widget.Filterable;
import android.widget.ImageView;
import android.widget.TextView;

import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.List;

import retrofit.Call;
import retrofit.JacksonConverterFactory;
import retrofit.Retrofit;
import teammeup.com.teammeup.API.RestService;
import teammeup.com.teammeup.R;
import teammeup.com.teammeup.domain.User;

public class MySportmateListAdapter extends BaseAdapter implements Filterable {


Context context;
List<User> users;
ListFragment parentFragment;

public MySportmateListAdapter(Context context, List<User> users) {
    super();
    this.context = context;
    this.users = users;
}
/*This is for the other usage!*/
public MySportmateListAdapter(Context context, ListFragment fragment) {
    super();
    this.context = context;
    parentFragment=fragment;
}


@Override
public int getCount() {
    return users.size();
}

@Override
public Object getItem(int position) {
    return users.get(position);
}

@Override
public long getItemId(int position) {
    return users.indexOf(getItem(position));
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    if (convertView == null) {
        LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = inflater.inflate(R.layout.user_on_list, parent, false);
    }
User user = users.get(position);
   /*Here are some textviews and other for a custom layout... and I sett hem with the datas from the user.*/   

    convertView.setTag(user.getId());
    return convertView;
}

@Override
public Filter getFilter() {
    Filter filter = new Filter() {
       /*For other usage, so it not neccessary now*/


    return filter;
}

}

所以我的问题是我想将该适配器用于Sportmates和Others片段，这些片段几乎相同但具有不同的数据。我认为在这种情况下我必须从ListFragments将数据传递给适配器。

我的问题是，如何以更好的方式处理这个领域？在哪里打开/关闭它？我在菜单上有一个注销选项，我想删除所有数据（整个Realm）。

我认为onResume / onPause打开/关闭将无效，因为注销。

我使用slidingtablayout作为选项卡，如果我是正确的，它会在打开的片段附近准备碎片，因此还有另外一个原因可以打开/关闭onResume / onPause。

你能帮助我，以正确的方式做到吗？

Answer 1

我们最近在我们的文档中添加了一个关于控制Realm生命周期的最佳实践部分：https://realm.io/docs/java/latest/#best-practices

除了尝试在注销时删除Realm文件，您还可以通过执行此处描述的操作来删除Realm中的所有数据：https://github.com/realm/realm-java/issues/1796

如何在Android上的ListFragment中显示Realm对象？

1 个答案: