Question

我的回收者视图没有显示我的问题，我想知道我是否忽略了某些东西。以下是相关课程。

SingleFragmentActivity

public abstract class SingleFragmentActivity  extends AppCompatActivity {

protected abstract Fragment createFragment();

@Override
public void onCreate(@Nullable Bundle savedInstanceState, @Nullable PersistableBundle persistentState) {
    super.onCreate(savedInstanceState, persistentState);
    setContentView(R.layout.activity_fragment);
    FragmentManager fm = getSupportFragmentManager();
    Fragment fragment = fm.findFragmentById(R.id.fragment_container);

    if (fragment == null) {
        fragment = createFragment();
        fm.beginTransaction().add(R.id.fragment_container, fragment).commit();
    }
}
}

ContactListActivity

import android.support.v4.app.Fragment;

import ...fragment.ContactListFragment;

public class ContactListActivity extends SingleFragmentActivity{

   @Override
   protected Fragment createFragment() {
       return new ContactListFragment();
   }
}

ContactListFragment

import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

public class ContactListFragment extends Fragment {

private RecyclerView mContactRecyclerView;
private ContactAdapter mAdapter;

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    View v = inflater.inflate(R.layout.fragment_contact_list, container, false);
    mContactRecyclerView = (RecyclerView) v.findViewById(R.id.contact_recycler_view);
    mContactRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
    updateUI();

    return v;
}

private void updateUI() {
    ContactList contactList = ContactList.get(getActivity());
    List<Contact> contacts = contactList.getContacts();
    mAdapter = new ContactAdapter(contacts);
    mContactRecyclerView.setAdapter(mAdapter);
}

private class ContactHolder extends RecyclerView.ViewHolder {

    private TextView mNameTextView;
    private TextView mPhoneNumberTextView;
    private Contact mContact;

    public ContactHolder(LayoutInflater inflater, ViewGroup parent) {
        super(inflater.inflate(R.layout.list_item_contact, parent, false));
        mNameTextView = (TextView) itemView.findViewById(R.id.contact_list_name);
        mPhoneNumberTextView = (TextView) itemView.findViewById(R.id.contact_list_phone);
    }

    public void bind(Contact contact) {
        mContact = contact;
        mNameTextView.setText(mContact.getmName());
        mPhoneNumberTextView.setText(mContact.getmPhone().getmWork());
    }
}

private class ContactAdapter extends RecyclerView.Adapter<ContactHolder> {

    private List<Contact> mContacts;

    public ContactAdapter(List<Contact> contacts) {
        mContacts = contacts;
    }

    @Override
    public ContactHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        LayoutInflater layoutInflater = LayoutInflater.from(getActivity());

        return new ContactHolder(layoutInflater, parent);
    }

    @Override
    public void onBindViewHolder(ContactHolder holder, int position) {
        Contact contact = mContacts.get(position);
        holder.bind(contact);
    }

    @Override
    public int getItemCount() {
        return mContacts.size();
    }
}
}

ContactList

public class ContactList {

private static ContactList sContactList;
private List<Contact> mContacts;

public static ContactList get(Context context) {
    if (sContactList == null) {
        sContactList = new ContactList(context);
    }
    return sContactList;
}

private ContactList(Context context) {
    mContacts = new ArrayList<>();
    for (int i = 0; i < 20; i++) {
        Contact contact = new Contact();
        Phone phone = new Phone();
        phone.setmWork("222-333-7676");
        contact.setmName("Andy Android");
        contact.setmPhone(phone);
        contact.setmSmallImageURL("www.purple.com");
        mContacts.add(contact);
    }
}

public List<Contact> getContacts() {
    return mContacts;
}

@Nullable
public Contact getContact(Phone phone) {
    for (Contact contact: mContacts) {
        if (contact.getmPhone().equals(phone)) {
            return contact;
        }
    }
    return null;
}
}

fragment_contact_list

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.RecyclerView
   xmlns:android="http://schemas.android.com/apk/res/android"
   android:id="@+id/contact_recycler_view"
   android:layout_width="match_parent"
   android:layout_height="match_parent"/>

list_item_contact

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <android.support.v7.widget.CardView
        xmlns:card_view="http://schemas.android.com/apk/res-auto"
        android:id="@+id/card_view"
        android:layout_width="match_parent"
        android:layout_height="@dimen/contact_list_card_height"
        android:background="@color/cardview_light_background"
        android:layout_margin="@dimen/contact_list_card_margin"
        card_view:cardCornerRadius="@dimen/contact_list_card_rounded_corner">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:weightSum="4"
            android:orientation="horizontal">

            <ImageView
                android:id="@+id/contact_list_image"
                android:layout_width="0dp"
                android:layout_height="match_parent"
                android:layout_margin="8dp"
                android:layout_weight="1"
                android:src="@drawable/favorite_not_selected"/>

            <LinearLayout
                android:layout_width="0dp"
                android:layout_height="match_parent"
                android:orientation="vertical"
                android:layout_weight="3">

                <TextView
                    android:id="@+id/contact_list_name"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:textStyle="bold"
                    android:textSize="@dimen/contact_list_name_size"
                    android:layout_marginStart="@dimen/contact_list_card_text_margin"
                    android:text=""/>

                <TextView
                    android:id="@+id/contact_list_phone"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_marginStart="@dimen/contact_list_card_text_margin"
                    android:text=""/>

            </LinearLayout>

        </LinearLayout>

    </android.support.v7.widget.CardView>

</LinearLayout>

注意省略了一些import语句。

谢谢！ Otterman

Answer 1

原来它与我的回收者视图无关。我的通用SingleFragmentActivity存在缺陷，应该是：

public abstract class SingleFragmentActivity  extends AppCompatActivity {

protected abstract Fragment createFragment();

@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);
   setContentView(R.layout.activity_fragment);
   FragmentManager fm = getSupportFragmentManager();
   Fragment fragment = fm.findFragmentById(R.id.fragment_container);
   if (fragment == null) {
      fragment = createFragment();
      fm.beginTransaction().add(R.id.fragment_container, fragment).commit();
   }
 }
}

没有显示的Recycler视图

1 个答案: