如何将图标添加到导航抽屉中的列表项

Question

我是 android 开发的初学者，所以请帮我做这件事 我想为导航抽屉中的项目添加图标。 我正在关注此网页上的教程http://www.androidhive.info/2015/04/android-getting-started-with-material-design/

这里是 NavDrawerItem.java ：

package info.androidhive.materialdesign.model;

/**
 * Created by Ravi on 29/07/15.
 */
public class NavDrawerItem {
    private boolean showNotify;
    private String title;


    public NavDrawerItem() {

    }

    public NavDrawerItem(boolean showNotify, String title) {
        this.showNotify = showNotify;
        this.title = title;
    }

    public boolean isShowNotify() {
        return showNotify;
    }

    public void setShowNotify(boolean showNotify) {
        this.showNotify = showNotify;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }
}

这里是 nav_drawer_row.xml

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

    <TextView
        android:id="@+id/title"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:paddingLeft="30dp"
        android:paddingTop="10dp"
        android:paddingBottom="10dp"
        android:textSize="15dp"
        android:textStyle="bold" />

</RelativeLayout>

这里是 srings.xml

strings.xml
<resources>
    <string name="app_name">Material Design</string>
    <string name="action_settings">Settings</string>
    <string name="action_search">Search</string>
    <string name="drawer_open">Open</string>
    <string name="drawer_close">Close</string>

    <string name="nav_item_home">Home</string>
    <string name="nav_item_friends">Friends</string>
    <string name="nav_item_notifications">Messages</string>

    <!-- navigation drawer item labels  -->
    <string-array name="nav_drawer_labels">
        <item>@string/nav_item_home</item>
        <item>@string/nav_item_friends</item>
        <item>@string/nav_item_notifications</item>
    </string-array>

    <string name="title_messages">Messages</string>
    <string name="title_friends">Friends</string>
    <string name="title_home">Home</string>
</resources>

这里是导航抽屉adapter.java：

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.TextView;

import java.util.Collections;
import java.util.List;

/**
 * Created by Ravi Tamada on 12-03-2015.
 */
public class NavigationDrawerAdapter extends RecyclerView.Adapter<NavigationDrawerAdapter.MyViewHolder> {
    List<NavDrawerItem> data = Collections.emptyList();
    private LayoutInflater inflater;
    private Context context;

    public NavigationDrawerAdapter(Context context, List<NavDrawerItem> data) {
        this.context = context;
        inflater = LayoutInflater.from(context);
        this.data = data;
    }

    public void delete(int position) {
        data.remove(position);
        notifyItemRemoved(position);
    }

    @Override
    public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View view = inflater.inflate(R.layout.nav_drawer_row, parent, false);
        MyViewHolder holder = new MyViewHolder(view);
        return holder;
    }

    @Override
    public void onBindViewHolder(MyViewHolder holder, int position) {
        NavDrawerItem current = data.get(position);
        holder.title.setText(current.getTitle());
    }

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

    class MyViewHolder extends RecyclerView.ViewHolder {
        TextView title;

        public MyViewHolder(View itemView) {
            super(itemView);
            title = (TextView) itemView.findViewById(R.id.title);
        }
    }
}

Answer 1

如果图标没有要执行的任务，只需为xml中的每个项目设置drawableLeft，图像就会自行添加。要提供一点填充，请在 xml 本身中使用 drawablePadding 属性。