方法listview使用

来源：互联网发布：第二梦软件编辑：程序博客网时间：2024/06/05 18:47

最近学习安卓，学了一段时间，感觉很乱，现在开始把每一个功能单独集合一下

这篇博文介绍listview，完整代码很适合我这样的新手看，

1、首先是activity_main.xml里面添加ListView控件

<ListView        android:id="@+id/list_book"        android:layout_width="fill_parent"        android:layout_weight="1"        android:layout_height="0dp"/>

这里还需要一个装item的视图文件list_one.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="horizontal"    android:padding="10dp">    <TextView        android:id="@+id/txt_bname"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="《第一行代码Android》"        android:textColor="#F3684A"        android:textSize="18sp" />    <TextView        android:id="@+id/txt_bauthor"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_marginLeft="20dp"        android:text="郭霖"        android:textColor="#44BDED"        android:textSize="18sp" /></LinearLayout>

然后编写一个类表示item的类型；这里示例为Book.java

package jay.com.listviewdemo4;/** * Created by Jay on 2015/9/22 0022. */public class Book {    private String bName;    private String bAuthor;    public Book() {    }    public Book(String bName, String bAuthor) {        this.bName = bName;        this.bAuthor = bAuthor;    }    public String getbName() {        return bName;    }    public String getbAuthor() {        return bAuthor;    }    public void setbName(String bName) {        this.bName = bName;    }    public void setbAuthor(String bAuthor) {        this.bAuthor = bAuthor;    }}

然后编写一个自己的Adapter（适配器的意思）类命名为MyAdapter.java

package jay.com.listviewdemo4;import android.content.Context;import android.util.SparseArray;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.ImageView;import android.widget.TextView;import java.util.ArrayList;/** * Created by Jay on 2015/9/22 0022. */public abstract class MyAdapter<T> extends BaseAdapter {    private ArrayList<T> mData;    private int mLayoutRes;           //布局id    public MyAdapter() {    }    public MyAdapter(ArrayList<T> mData, int mLayoutRes) {        this.mData = mData;        this.mLayoutRes = mLayoutRes;    }    @Override    public int getCount() {        return mData != null ? mData.size() : 0;    }    @Override    public T getItem(int position) {        return mData.get(position);    }    @Override    public long getItemId(int position) {        return position;    }    @Override    public View getView(int position, View convertView, ViewGroup parent) {        ViewHolder holder = ViewHolder.bind(parent.getContext(), convertView, parent, mLayoutRes                , position);        bindView(holder, getItem(position));        return holder.getItemView();    }    public abstract void bindView(ViewHolder holder, T obj);    //添加一个元素    public void add(T data) {        if (mData == null) {            mData = new ArrayList<>();        }        mData.add(data);        notifyDataSetChanged();    }    //往特定位置，添加一个元素    public void add(int position, T data) {        if (mData == null) {            mData = new ArrayList<>();        }        mData.add(position, data);        notifyDataSetChanged();    }    public void remove(T data) {        if (mData != null) {            mData.remove(data);        }        notifyDataSetChanged();    }    public void remove(int position) {        if (mData != null) {            mData.remove(position);        }        notifyDataSetChanged();    }    public void clear() {        if (mData != null) {            mData.clear();        }        notifyDataSetChanged();    }    public static class ViewHolder {        private SparseArray<View> mViews;   //存储ListView 的 item中的View        private View item;                  //存放convertView        private int position;               //游标        private Context context;            //Context上下文        //构造方法，完成相关初始化        private ViewHolder(Context context, ViewGroup parent, int layoutRes) {            mViews = new SparseArray<>();            this.context = context;            View convertView = LayoutInflater.from(context).inflate(layoutRes, parent, false);            convertView.setTag(this);            item = convertView;        }        //绑定ViewHolder与item        public static ViewHolder bind(Context context, View convertView, ViewGroup parent,                                      int layoutRes, int position) {            ViewHolder holder;            if (convertView == null) {                holder = new ViewHolder(context, parent, layoutRes);            } else {                holder = (ViewHolder) convertView.getTag();                holder.item = convertView;            }            holder.position = position;            return holder;        }        @SuppressWarnings("unchecked")        public <T extends View> T getView(int id) {            T t = (T) mViews.get(id);            if (t == null) {                t = (T) item.findViewById(id);                mViews.put(id, t);            }            return t;        }        /**         * 获取当前条目         */        public View getItemView() {            return item;        }        /**         * 获取条目位置         */        public int getItemPosition() {            return position;        }        /**         * 设置文字         */        public ViewHolder setText(int id, CharSequence text) {            View view = getView(id);            if (view instanceof TextView) {                ((TextView) view).setText(text);            }            return this;        }        /**         * 设置图片         */        public ViewHolder setImageResource(int id, int drawableRes) {            View view = getView(id);            if (view instanceof ImageView) {                ((ImageView) view).setImageResource(drawableRes);            } else {                view.setBackgroundResource(drawableRes);            }            return this;        }        /**         * 设置点击监听         */        public ViewHolder setOnClickListener(int id, View.OnClickListener listener) {            getView(id).setOnClickListener(listener);            return this;        }        /**         * 设置可见         */        public ViewHolder setVisibility(int id, int visible) {            getView(id).setVisibility(visible);            return this;        }        /**         * 设置标签         */        public ViewHolder setTag(int id, Object obj) {            getView(id).setTag(obj);            return this;        }        //其他方法可自行扩展    }}

然后是MainActivity.java

package jay.com.listviewdemo4;import android.content.Context;import android.os.Bundle;import android.support.v7.app.AppCompatActivity;import android.widget.ListView;import java.util.ArrayList;import java.util.List;public class MainActivity extends AppCompatActivity {    private Context mContext;    private ListView list_book;    private ListView list_app;    private MyAdapter<App> myAdapter1 = null;    private MyAdapter<Book> myAdapter2 = null;    private List<App> mData1 = null;    private List<Book> mData2 = null;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        mContext = MainActivity.this;        init();    }    private void init() {        list_book = (ListView) findViewById(R.id.list_book);        list_app = (ListView) findViewById(R.id.list_app);        //数据初始化        mData1 = new ArrayList<App>();        mData1.add(new App(R.mipmap.iv_icon_baidu,"百度1"));        mData1.add(new App(R.mipmap.iv_icon_douban,"豆瓣1"));        mData1.add(new App(R.mipmap.iv_icon_zhifubao,"支付宝1"));        mData2 = new ArrayList<Book>();        mData2.add(new Book("《第一行代码Android》","郭霖"));        mData2.add(new Book("《Android群英传》","徐宜生"));        mData2.add(new Book("《Android开发艺术探索》","任玉刚"));        //Adapter初始化        myAdapter1 = new MyAdapter<App>((ArrayList)mData1,R.layout.item_one) {            @Override            public void bindView(ViewHolder holder, App obj) {                holder.setImageResource(R.id.img_icon,obj.getaIcon());                holder.setText(R.id.txt_aname,obj.getaName());            }        };        myAdapter2 = new MyAdapter<Book>((ArrayList)mData2,R.layout.item_two) {            @Override            public void bindView(ViewHolder holder, Book obj) {                holder.setText(R.id.txt_bname,obj.getbName());                holder.setText(R.id.txt_bauthor,obj.getbAuthor());            }        };        //ListView设置下Adapter：        list_book.setAdapter(myAdapter2);        list_app.setAdapter(myAdapter1);    }}

使用时只需要更换ID就行了

1 0