java - 无法通过数据绑定(bind)在 Fragment 上使用 RecyclerView

Question

现在我尝试使用数据绑定(bind)实现 RecyclerView。并且这个 RecyclerView 实例附加在 Fragment 中。

我有关于 this web page 的引用，此代码有效，但我的无效。我不知道为什么我有错误。此外，我的应用程序没有收到任何错误消息。它只是不起作用。

也许，这可能是一个错误信息，但我无法调试这个问题

E/AndroidRuntime: FATAL EXCEPTION: main
                                                 Process: net.azurewebsites.irrationnelle.testandroidstudio, PID: 3828
                                                 android.content.res.Resources$NotFoundException: String resource ID #0xa
                                                     at android.content.res.Resources.getText(Resources.java:335)
                                                     at android.widget.TextView.setText(TextView.java:4555)
                                                     at net.azurewebsites.irrationnelle.testandroidstudio.databinding.MainRecyclerItemsBinding.executeBindings(MainRecyclerItemsBinding.java:113)
                                                     at android.databinding.ViewDataBinding.executeBindingsInternal(ViewDataBinding.java:379)
                                                     at android.databinding.ViewDataBinding.executePendingBindings(ViewDataBinding.java:351)
                                                     at android.databinding.ViewDataBinding$6.run(ViewDataBinding.java:178)
                                                     at android.databinding.ViewDataBinding$7.doFrame(ViewDataBinding.java:251)
                                                     at android.view.Choreographer$CallbackRecord.run(Choreographer.java:872)
                                                     at android.view.Choreographer.doCallbacks(Choreographer.java:686)
                                                     at android.view.Choreographer.doFrame(Choreographer.java:618)
                                                     at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:860)
                                                     at android.os.Handler.handleCallback(Handler.java:751)
                                                     at android.os.Handler.dispatchMessage(Handler.java:95)
                                                     at android.os.Looper.loop(Looper.java:154)
                                                     at android.app.ActivityThread.main(ActivityThread.java:6119)
                                                     at java.lang.reflect.Method.invoke(Native Method)
                                                     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
                                                     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)

下面是我的代码。

我需要你的帮助，我花了大约 3 天的时间来解决这个问题......谢谢。

main_recycler_items.xml

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android">
    <data>

        <variable
            name="item"
            type="net.azurewebsites.irrationnelle.testandroidstudio.vo.MainItem"/>
    </data>

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

        <TextView
            android:id="@+id/band_name"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="5"
            android:gravity="center_vertical"
            android:padding="10dp"
            android:text="@{item.bandName}" />

        <TextView
            android:id="@+id/music_count"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:gravity="center"
            android:text="@{item.bandCount}"
            android:textAlignment="center" />

        <ImageView
            android:id="@+id/scroll_button"
            android:layout_width="3dp"
            android:layout_height="30dp"
            android:layout_gravity="center"
            android:layout_weight="1"
            android:src="@drawable/ic_keyboard_arrow_down_black_36dp" />

    </LinearLayout>
</layout>

/vo/MainItem.java

package net.azurewebsites.irrationnelle.testandroidstudio.vo;

public class MainItem {
    private int bandCount;
    private String bandName;

    public MainItem(int bandCount, String bandName) {
        this.bandCount = bandCount;
        this.bandName = bandName;
    }

    public int getBandCount() {
        return bandCount;
    }

    public void setBandCount(int bandCount) {
        this.bandCount = bandCount;
    }

    public String getBandName() {
        return bandName;
    }

    public void setBandName(String bandName) {
        this.bandName = bandName;
    }
}

fragment _main.xml

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <android.support.v7.widget.RecyclerView
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:id="@+id/main_recylcer_view"
            android:scrollbars="vertical">

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

    </LinearLayout>
</layout>

MainViewHolder.java

package net.azurewebsites.irrationnelle.testandroidstudio;

import android.databinding.DataBindingUtil;
import android.support.v7.widget.RecyclerView;
import android.view.View;

import net.azurewebsites.irrationnelle.testandroidstudio.databinding.MainRecyclerItemsBinding;
import net.azurewebsites.irrationnelle.testandroidstudio.vo.MainItem;

public class MainViewHolder extends RecyclerView.ViewHolder {
    private MainRecyclerItemsBinding binding;

    public MainViewHolder(View itemView) {
        super(itemView);
        binding = DataBindingUtil.bind(itemView);
    }

    public void bind(MainItem item) {
        binding.setItem(item);
    }
}

MainRecyclerViewAdapter.java

package net.azurewebsites.irrationnelle.testandroidstudio;

import android.content.Context;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import net.azurewebsites.irrationnelle.testandroidstudio.vo.MainItem;

import java.util.List;

public class MainRecyclerViewAdapter extends RecyclerView.Adapter<MainViewHolder> {
    private List<MainItem> items;

    public MainRecyclerViewAdapter(List<MainItem> items) {
        this.items = items;
    }

    @Override
    public MainViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        Context context = parent.getContext();
        LayoutInflater inflater = LayoutInflater.from(context);
        View statusContainer = inflater.inflate(R.layout.main_recycler_items, parent, false);
        return new MainViewHolder(statusContainer);
    }

    @Override
    public void onBindViewHolder(MainViewHolder holder, int position) {
        MainItem status = items.get(position);
        holder.bind(status);
    }

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

主要 fragment .java

package net.azurewebsites.irrationnelle.testandroidstudio;

import android.app.Fragment;
import android.content.Context;
import android.databinding.DataBindingUtil;
import android.os.Bundle;
import android.support.annotation.Nullable;
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 net.azurewebsites.irrationnelle.testandroidstudio.databinding.FragmentMainBinding;
import net.azurewebsites.irrationnelle.testandroidstudio.databinding.MainRecyclerItemsBinding;
import net.azurewebsites.irrationnelle.testandroidstudio.vo.MainItem;

import java.util.ArrayList;
import java.util.List;

public class MainFragments extends Fragment {
    private FragmentMainBinding binding;

    private RecyclerView recyclerView;
    private MainRecyclerViewAdapter adapter;
    private List<MainItem> items;

    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {
        binding = DataBindingUtil.inflate(inflater, R.layout.fragment_main, container, false);
        View view = binding.getRoot();

        recyclerView = binding.mainRecylcerView;
        recyclerView.setLayoutManager(new LinearLayoutManager(getActivity(), LinearLayoutManager.VERTICAL, false));

        items = new ArrayList<>();

        items.add(new MainItem(10, "Les Hiers"));
        items.add(new MainItem(5, "Zakuro"));

        adapter = new MainRecyclerViewAdapter(items);

        recyclerView.setAdapter(adapter);

        return view;
    }
}

主 Activity .java

package net.azurewebsites.irrationnelle.testandroidstudio;

import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.databinding.DataBindingUtil;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.design.widget.BottomNavigationView;
import android.support.v7.app.AppCompatActivity;
import android.view.MenuItem;
import android.view.View;
import android.widget.TextView;

import com.getbase.floatingactionbutton.FloatingActionButton;

import net.azurewebsites.irrationnelle.testandroidstudio.databinding.ActivityMainBinding;
import net.azurewebsites.irrationnelle.testandroidstudio.databinding.FabTestBinding;

public class MainActivity extends AppCompatActivity {
    private ActivityMainBinding activityMainBinding;

    private TextView mTextMessage;

    private MainFragments mainFragments;

    private BottomNavigationView.OnNavigationItemSelectedListener mOnNavigationItemSelectedListener
            = new BottomNavigationView.OnNavigationItemSelectedListener() {

        @Override
        public boolean onNavigationItemSelected(@NonNull MenuItem item) {
            switch (item.getItemId()) {
                case R.id.navigation_home:
                    mTextMessage.setText(R.string.title_home);
                    return true;
                case R.id.navigation_dashboard:
                    mTextMessage.setText(R.string.title_dashboard);
                    return true;
                case R.id.navigation_notifications:
                    mTextMessage.setText(R.string.title_notifications);
                    return true;
            }
            return false;
        }

    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        activityMainBinding = DataBindingUtil.setContentView(this, R.layout.activity_main);

        mainFragments = new MainFragments();

        FragmentManager fm = getFragmentManager();
        FragmentTransaction fragmentTransaction = fm.beginTransaction();
        fragmentTransaction.replace(R.id.main_fragment, mainFragments);
        fragmentTransaction.commit();

    }

}

Answer 1

你还没有用ViewHolder绑定(bind)数据，在onBindViewHolder()中绑定(bind)它

@Override
public void onBindViewHolder(MainViewHolder holder, int position) {
    MainItem status = items.get(position);

    holder.bind(status);
}

更新

badgeCount 是int值，需要和String拼接

android:text="@{`` + item.bandCount}"

或

android:text="@{String.valueOf(item.bandCount)}"