Question

我有一个基本导航抽屉活动，它会加载一个片段。片段。该片段在其布局中具有回收器视图。回收站视图有一个适配器，使用Glide从互联网加载图像。我无法加载图像。（已在清单中添加了Internet权限）。我的基地活动是：

import android.net.Uri;
import android.os.Bundle;
import android.support.design.widget.NavigationView;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentTransaction;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.RelativeLayout;
import android.widget.Toast;

public class BaseActivity extends AppCompatActivity
        implements NavigationView.OnNavigationItemSelectedListener, Item1Fragment.OnFragmentInteractionListener {

    /**
     * Frame layout: Which is going to be used as parent layout for child activity layout.
     * This layout is protected so that child activity can access this
     */
    protected RelativeLayout relativeLayout;


    @Override
    protected void onCreate(Bundle savedInstanceState) {

        relativeLayout = (RelativeLayout) findViewById(R.id.content_frame);

        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_base);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
                this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
        drawer.setDrawerListener(toggle);
        toggle.syncState();

        NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
        navigationView.setNavigationItemSelectedListener(this);


        //Add the Very First i.e Squad Fragment to the Container
        Fragment item1Fragment = new Item1Fragment();
        FragmentTransaction fragmentTransaction = getSupportFragmentManager().beginTransaction();
        fragmentTransaction.add(R.id.content_frame, item1Fragment, null);
        fragmentTransaction.commit();
    }

    @Override
    public void onFragmentInteraction(Uri uri) {

    }

    @Override
    public void onBackPressed() {
        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        if (drawer.isDrawerOpen(GravityCompat.START)) {
            drawer.closeDrawer(GravityCompat.START);
        } else {
            super.onBackPressed();
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.base, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }

    @SuppressWarnings("StatementWithEmptyBody")
    @Override
    public boolean onNavigationItemSelected(MenuItem item) {
        // Handle navigation view item clicks here.
        int id = item.getItemId();
        FragmentTransaction fragmentTransaction = this.getSupportFragmentManager().beginTransaction();
        if (id == R.id.nav_camera) {
            Fragment item1Fragment = new Item1Fragment();
            fragmentTransaction.replace(R.id.content_frame, item1Fragment);
            fragmentTransaction.commit();
        } else if (id == R.id.nav_gallery) {
            Fragment item2Fragment = new Item2Fragment();
            fragmentTransaction.replace(R.id.content_frame, item2Fragment);
            fragmentTransaction.commit();
        } else if (id == R.id.nav_slideshow) {
            Toast.makeText(getApplicationContext(), "333", Toast.LENGTH_SHORT).show();
        } else if (id == R.id.nav_manage) {
            Toast.makeText(getApplicationContext(), "444", Toast.LENGTH_SHORT).show();
        } else if (id == R.id.nav_share) {
            Toast.makeText(getApplicationContext(), "555", Toast.LENGTH_SHORT).show();
        } else if (id == R.id.nav_send) {
            Toast.makeText(getApplicationContext(), "666", Toast.LENGTH_SHORT).show();
        }

        DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
        drawer.closeDrawer(GravityCompat.START);
        return true;
    }

    // Container Activity must implement this interface
    public interface OnHeadlineSelectedListener {
        public void onArticleSelected(int position);
    }
}

活动布局是：

<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true" android:background="@color/colorPrimary"
    tools:openDrawer="start">

    <RelativeLayout
        android:id="@+id/content_frame"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <include
        layout="@layout/app_bar_base"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

    <android.support.design.widget.NavigationView
        android:id="@+id/nav_view"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:fitsSystemWindows="true"
        app:headerLayout="@layout/nav_header_base"
        app:menu="@menu/activity_base_drawer" />
</android.support.v4.widget.DrawerLayout>

片段：

import android.content.Context;
import android.content.res.Configuration;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v7.widget.GridLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import java.util.ArrayList;

public class Item1Fragment extends Fragment {

    private OnFragmentInteractionListener mListener;
    private ArrayList<ImageModel> data = new ArrayList<>();
    private GalleryAdapter mAdapter;
    private RecyclerView mRecyclerView;

    public static String IMGS[] = {
            "https://images.unsplash.com/photo-1444090542259-0af8fa96557e?q=80&fm=jpg&w=1080&fit=max&s=4b703b77b42e067f949d14581f35019b",
            "https://images.unsplash.com/photo-1439546743462-802cabef8e97?dpr=2&fit=crop&fm=jpg&h=725&q=50&w=1300",
            "https://images.unsplash.com/photo-1441155472722-d17942a2b76a?q=80&fm=jpg&w=1080&fit=max&s=80cb5dbcf01265bb81c5e8380e4f5cc1",
            "https://images.unsplash.com/photo-1437651025703-2858c944e3eb?dpr=2&fit=crop&fm=jpg&h=725&q=50&w=1300",
            "https://images.unsplash.com/photo-1431538510849-b719825bf08b?dpr=2&fit=crop&fm=jpg&h=725&q=50&w=1300",
            "https://images.unsplash.com/photo-1434873740857-1bc5653afda8?dpr=2&fit=crop&fm=jpg&h=725&q=50&w=1300",
            "https://images.unsplash.com/photo-1439396087961-98bc12c21176?dpr=2&fit=crop&fm=jpg&h=725&q=50&w=1300",
            "https://images.unsplash.com/photo-1433616174899-f847df236857?dpr=2&fit=crop&fm=jpg&h=725&q=50&w=1300",
            "https://images.unsplash.com/photo-1438480478735-3234e63615bb?dpr=2&fit=crop&fm=jpg&h=725&q=50&w=1300",
            "https://images.unsplash.com/photo-1438027316524-6078d503224b?dpr=2&fit=crop&fm=jpg&h=725&q=50&w=1300"
    };

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        for (int i = 0; i < IMGS.length; i++) {

            ImageModel imageModel = new ImageModel();
            imageModel.setName("Image " + i);
            imageModel.setUrl(IMGS[i]);
            data.add(imageModel);
        }

        View view = inflater.inflate(R.layout.fragment_item1,container,false);
        mRecyclerView = (RecyclerView)view.findViewById(R.id.list);
        if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE) {
            mRecyclerView.setLayoutManager(new GridLayoutManager(getActivity(), 3));
        }else{
            mRecyclerView.setLayoutManager(new GridLayoutManager(getActivity(), 2));
        }

        mRecyclerView.setHasFixedSize(true);
        mAdapter = new GalleryAdapter(getActivity().getApplicationContext(), data);
        mRecyclerView.setAdapter(mAdapter);

        return view;
    }

    //
    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
        if (context instanceof OnFragmentInteractionListener) {
            mListener = (OnFragmentInteractionListener) context;
        } else {
            throw new RuntimeException(context.toString()
                    + " must implement OnFragmentInteractionListener");
        }
    }

    @Override
    public void onDetach() {
        super.onDetach();
        mListener = null;
    }

    public interface OnFragmentInteractionListener {
        // TODO: Update argument type and name
        void onFragmentInteraction(Uri uri);
    }
}

片段布局：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    tools:context="com.akl.nav2.Item1Fragment">

    <android.support.v7.widget.RecyclerView
        android:id="@+id/list" android:background="#FFBB00"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="@string/appbar_scrolling_view_behavior" />
</RelativeLayout>

适配器：

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

import com.bumptech.glide.Glide;
import com.bumptech.glide.load.engine.DiskCacheStrategy;

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

/**
 * Created by akl on 3/12/2016.
 */
public class GalleryAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {

    Context context;
    List<ImageModel> data = new ArrayList<>();

    public GalleryAdapter(Context context, List<ImageModel> data) {
        this.context = context;
        this.data = data;
    }

    @Override
    public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        RecyclerView.ViewHolder viewHolder;
        View v;
        v = LayoutInflater.from(parent.getContext()).inflate(
                R.layout.list_item, parent, false);
        viewHolder = new MyItemHolder(v);

        return viewHolder;
    }

    @Override
    public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {

        Glide.with(context).load(data.get(position).getUrl())
                .thumbnail(0.5f)
                .override(200, 200)
                .crossFade()
                .diskCacheStrategy(DiskCacheStrategy.ALL)
                .into(((MyItemHolder) holder).mImg);
    }

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

    public static class MyItemHolder extends RecyclerView.ViewHolder {
        ImageView mImg;

        public MyItemHolder(View itemView) {
            super(itemView);

            mImg = (ImageView) itemView.findViewById(R.id.item_img);
        }
    }
}

清单：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.akl.nav2">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity
            android:name=".BaseActivity"
            android:label="@string/app_name"
            android:theme="@style/AppTheme.NoActionBar">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category
                    android:name="android.intent.category.LAUNCHER"
                    android:theme="@style/AppTheme.NoActionBar" />
            </intent-filter>
        </activity>

    </application>
    <uses-permission android:name="android.permission.INTERNET" />
</manifest>

Answer 1

代码很好。 @HoangNguyen建议的干净构建足以使代码运行。

recyclerview没有在片段中加载适配器值

1 个答案: