Android Studio中带有imageview的listview

Question

我是Android Studio的新手，我想尝试使用左侧显示的列表视图，如下所示。 我设法用一个简单的列表项创建了这样的列表，但是当我用ActivityList更改简单的项列表时，它不再起作用。

如何更改ArrayList以将图像视图与名称组合在一起？ 我认为可以通过使用包含imageview和name而不是string的新类来实现。

码：

public class MainActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ListView friendsListView = findViewById(R.id.friendListView);
        final ArrayList<String> myFriends = new ArrayList<String>(asList("Mark","Jane","Sussy","Jan"));
        ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(this,android.R.layout.activity_list_item
                , myFriends);
        friendsListView.setAdapter(arrayAdapter);
        friendsListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
                Toast.makeText(getApplicationContext(), "Hello " + myFriends.get(i), Toast.LENGTH_LONG).show();
            }
        });
    }
}

Answer 1

没错，您需要为列表项创建一个模型类； 该模型类包含的内容因项目而异； 例如，在您共享的图片中，列表项具有图片的典型名称和标题； 所以你的模型课。

接下来，使用ArrayList<Item>代替ArrayList<String> ArrayList<Item> ； 其中Item是模型类

第三，您需要创建一个自ArrayAdapter<Item>扩展的自定义适配器； 那是因为您不能使用内置列表项布局“ android.R.layout.activity_list_item”，因为它只为您提供单个字符串； 现在您需要伴随它。

下面是一个简单的演示

模型类（Item.java）

class Item {

    private int mPicture;
    private String mTitle;

    int getPicture() {
        return mPicture;
    }

    Item(int picture, String title) {
        mPicture = picture;
        mTitle = title;
    }

    String getTitle() {
        return mTitle;
    }

}

列表视图适配器（ListViewAdapter.java）

public class ListViewAdapter extends ArrayAdapter<Item> {

    ListViewAdapter(@NonNull Context context, ArrayList<Item> items) {
        super(context, 0, items);
    }

    @NonNull
    @Override
    public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent) {

        View listItem = convertView;
        if (listItem == null) {
            listItem = LayoutInflater.from(getContext()).inflate(R.layout.list_item, parent, false);
        }

        // Get the {@link Word} object located at this position in the list
        Item currentItem = getItem(position);

        ImageView picture = listItem.findViewById(R.id.IvPicture);
        picture.setBackgroundResource(currentItem.getPicture());

        TextView title = listItem.findViewById(R.id.tvTitle);
        title.setText(currentItem.getTitle());

        return listItem;
    }

}

活动课

 public class MainActivity extends AppCompatActivity{

       @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);

            ArrayList<Item> items = new ArrayList<>();
            items.add(new Item(R.drawable.item1, "Item1"));
            items.add(new Item(R.drawable.item2, "Item2"));
            items.add(new Item(R.drawable.item3, "Item3"));

            ListViewAdapter adapter = new ListViewAdapter(this, items);
            ListView listView = findViewById(R.id.listView);
            listView.setAdapter(adapter);

        }
}

活动布局（activity_main.xml）

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

    <ListView
        android:id="@+id/listView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
    </ListView>

</LinearLayout>

列表项布局（list_item.xml）

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

    <ImageView
        android:id="@+id/IvPicture"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

    <TextView
        android:id="@+id/tvTitle"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="item" />

</LinearLayout>

您必须在res / drawable中将3张图像分别命名为item1，item2和item3

希望这能满足您的需求。

Answer 2

activity_main.xml中

<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"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity"
    android:background="@color/grey_300"
    >

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

</RelativeLayout>

cards_layout.xml代码：

<android.support.v7.widget.CardView
    android:id="@+id/card_view"
    xmlns:card_view="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    card_view:cardBackgroundColor="@color/color_white"
    card_view:cardCornerRadius="10dp"
    card_view:cardElevation="5dp"
    card_view:cardUseCompatPadding="true">

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

        <ImageView
            android:id="@+id/imageView"
            android:tag="image_tag"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_margin="5dp"
            android:layout_weight="1"
            android:src="@drawable/ic_launcher"/>

        <LinearLayout
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_marginTop="12dp"
            android:layout_weight="2"
            android:orientation="vertical"
            >

            <TextView
                android:id="@+id/textViewName"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center_horizontal"
                android:layout_marginTop="10dp"
                android:text="Android Name"
                android:textAppearance="?android:attr/textAppearanceLarge"/>

            <TextView
                android:id="@+id/textViewVersion"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center_horizontal"
                android:layout_marginTop="10dp"

                android:text="Android Version"
                android:textAppearance="?android:attr/textAppearanceMedium"/>

        </LinearLayout>
    </LinearLayout>

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

menu_main.xml代码：

<menu 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"
    tools:context=".MainActivity">
    <item android:id="@+id/add_item"
        android:title="Add"
        android:orderInCategory="100"
        app:showAsAction="always"/>
</menu>

MainActivity.java

包com.journaldev.recyclerviewcardview;

import android.content.Context;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.DefaultItemAnimator;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {

    private static RecyclerView.Adapter adapter;
    private RecyclerView.LayoutManager layoutManager;
    private static RecyclerView recyclerView;
    private static ArrayList<DataModel> data;
    static View.OnClickListener myOnClickListener;
    private static ArrayList<Integer> removedItems;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        myOnClickListener = new MyOnClickListener(this);

        recyclerView = (RecyclerView) findViewById(R.id.my_recycler_view);
        recyclerView.setHasFixedSize(true);

        layoutManager = new LinearLayoutManager(this);
        recyclerView.setLayoutManager(layoutManager);
        recyclerView.setItemAnimator(new DefaultItemAnimator());

        data = new ArrayList<DataModel>();
        for (int i = 0; i < MyData.nameArray.length; i++) {
            data.add(new DataModel(
                    MyData.nameArray[i],
                    MyData.versionArray[i],
                    MyData.id_[i],
                    MyData.drawableArray[i]
            ));
        }

        removedItems = new ArrayList<Integer>();

        adapter = new CustomAdapter(data);
        recyclerView.setAdapter(adapter);
    }


    private static class MyOnClickListener implements View.OnClickListener {

        private final Context context;

        private MyOnClickListener(Context context) {
            this.context = context;
        }

        @Override
        public void onClick(View v) {
            removeItem(v);
        }

        private void removeItem(View v) {
            int selectedItemPosition = recyclerView.getChildPosition(v);
            RecyclerView.ViewHolder viewHolder
                    = recyclerView.findViewHolderForPosition(selectedItemPosition);
            TextView textViewName
                    = (TextView) viewHolder.itemView.findViewById(R.id.textViewName);
            String selectedName = (String) textViewName.getText();
            int selectedItemId = -1;
            for (int i = 0; i < MyData.nameArray.length; i++) {
                if (selectedName.equals(MyData.nameArray[i])) {
                    selectedItemId = MyData.id_[i];
                }
            }
            removedItems.add(selectedItemId);
            data.remove(selectedItemPosition);
            adapter.notifyItemRemoved(selectedItemPosition);
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        super.onCreateOptionsMenu(menu);
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        super.onOptionsItemSelected(item);
        if (item.getItemId() == R.id.add_item) {
           //check if any items to add
            if (removedItems.size() != 0) {
                addRemovedItemToList();
            } else {
                Toast.makeText(this, "Nothing to add", Toast.LENGTH_SHORT).show();
            }
        }
        return true;
    }

    private void addRemovedItemToList() {
        int addItemAtListPosition = 3;
        data.add(addItemAtListPosition, new DataModel(
                MyData.nameArray[removedItems.get(0)],
                MyData.versionArray[removedItems.get(0)],
                MyData.id_[removedItems.get(0)],
                MyData.drawableArray[removedItems.get(0)]
        ));
        adapter.notifyItemInserted(addItemAtListPosition);
        removedItems.remove(0);
    }
}

CustomAdapter.java

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

import java.util.ArrayList;

public class CustomAdapter extends RecyclerView.Adapter<CustomAdapter.MyViewHolder> {

    private ArrayList<DataModel> dataSet;

    public static class MyViewHolder extends RecyclerView.ViewHolder {

        TextView textViewName;
        TextView textViewVersion;
        ImageView imageViewIcon;

        public MyViewHolder(View itemView) {
            super(itemView);
            this.textViewName = (TextView) itemView.findViewById(R.id.textViewName);
            this.textViewVersion = (TextView) itemView.findViewById(R.id.textViewVersion);
            this.imageViewIcon = (ImageView) itemView.findViewById(R.id.imageView);
        }
    }

    public CustomAdapter(ArrayList<DataModel> data) {
        this.dataSet = data;
    }

    @Override
    public MyViewHolder onCreateViewHolder(ViewGroup parent,
                                           int viewType) {
        View view = LayoutInflater.from(parent.getContext())
                .inflate(R.layout.cards_layout, parent, false);

        view.setOnClickListener(MainActivity.myOnClickListener);

        MyViewHolder myViewHolder = new MyViewHolder(view);
        return myViewHolder;
    }

    @Override
    public void onBindViewHolder(final MyViewHolder holder, final int listPosition) {

        TextView textViewName = holder.textViewName;
        TextView textViewVersion = holder.textViewVersion;
        ImageView imageView = holder.imageViewIcon;

        textViewName.setText(dataSet.get(listPosition).getName());
        textViewVersion.setText(dataSet.get(listPosition).getVersion());
        imageView.setImageResource(dataSet.get(listPosition).getImage());
    }

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

DataModel.java

public class DataModel {

    String name;
    String version;
    int id_;
    int image;

    public DataModel(String name, String version, int id_, int image) {
        this.name = name;
        this.version = version;
        this.id_ = id_;
        this.image=image;
    }

    public String getName() {
        return name;
    }

    public String getVersion() {
        return version;
    }

    public int getImage() {
        return image;
    }

    public int getId() {
        return id_;
    }
}

MyData.java

public class MyData {

    static String[] nameArray = {"Cupcake", "Donut", "Eclair", "Froyo", "Gingerbread", "Honeycomb", "Ice Cream Sandwich","JellyBean", "Kitkat", "Lollipop", "Marshmallow"};
    static String[] versionArray = {"1.5", "1.6", "2.0-2.1", "2.2-2.2.3", "2.3-2.3.7", "3.0-3.2.6", "4.0-4.0.4", "4.1-4.3.1", "4.4-4.4.4", "5.0-5.1.1","6.0-6.0.1"};

    static Integer[] drawableArray = {R.drawable.cupcake, R.drawable.donut, R.drawable.eclair,
            R.drawable.froyo, R.drawable.gingerbread, R.drawable.honeycomb, R.drawable.ics,
            R.drawable.jellybean, R.drawable.kitkat, R.drawable.lollipop,R.drawable.marsh};

    static Integer[] id_ = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
}

Answer 3

public class MainActivity extends AppCompatActivity {


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        ListView friendsListView = findViewById(R.id.friendListView);

        final ArrayList<Item> items = new ArrayList<>();
        items.add(new Item(R.drawable.abc, "Item1"));
        items.add(new Item(R.drawable.def, "Item2"));


        ListViewAdapter adapter = new ListViewAdapter(this, items);

        ListView.setAdapter(adapter);

        friendsListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {

                Toast.makeText(getApplicationContext(), "Hello " + items.get(i), Toast.LENGTH_LONG).show();

            }
        });
    }
}