首先还是上效果图,该ListView由四个控件组成,左边是一个图标,中间是两个TextView用于显示标题和描述,右边是一个TextView用于显示时间。
编写每一项对应的实体类
package cn.edu.zafu.myapplication; /** * Created by Administrator on 2015/1/1. */ public class Item { private int resId; private String title; private String description; private String time; public Item(int resId, String title, String description, String time) { this.resId = resId; this.title = title; this.description = description; this.time = time; } public int getResId() { return resId; } public void setResId(int resId) { this.resId = resId; } public String getTitle() { return title; } public void setTitle(String title) { this.title = title; } public String getDescription() { return description; } public void setDescription(String description) { this.description = description; } public String getTime() { return time; } public void setTime(String time) { this.time = time; } }
编写每一项对应的布局文件
<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="wrap_content" android:minHeight="60dp" tools:context=".MainActivity"> <ImageView android:id="@+id/item_icon" android:layout_width="32dp" android:layout_height="32dp" android:layout_alignParentLeft="true" android:layout_marginLeft="10dp" android:layout_centerVertical="true" /> <LinearLayout android:layout_toRightOf="@id/item_icon" android:layout_width="wrap_content" android:layout_height="match_parent" android:layout_centerVertical="true" android:layout_marginLeft="10dp" android:gravity="center_vertical" android:orientation="vertical" > <TextView android:id="@+id/item_title" android:layout_width="wrap_content" android:layout_height="wrap_content" android:textSize="18sp" /> <TextView android:id="@+id/item_description" android:layout_width="wrap_content" android:layout_height="wrap_content" android:textColor="#aaa" android:textSize="15sp" /> </LinearLayout> <TextView android:id="@+id/item_time" android:layout_width="60dp" android:layout_height="wrap_content" android:layout_alignParentRight="true" android:layout_centerVertical="true" android:textSize="12sp" /> </RelativeLayout>
主布局文件
<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" tools:context=".MainActivity"> <ListView android:id="@+id/listview" android:layout_width="match_parent" android:layout_height="match_parent" ></ListView> </RelativeLayout>
继承ArrayAdapter编写适配器
package cn.edu.zafu.myapplication; import android.content.Context; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.ArrayAdapter; import android.widget.ImageView; import android.widget.TextView; import java.util.List; public class MyArrayAdapter extends ArrayAdapter<Item> { private int resourceId; public MyArrayAdapter(Context context, int resource, List<Item> objects) { super(context, resource, objects); this.resourceId=resource; } @Override public View getView(int position, View convertView, ViewGroup parent) { Item item = getItem(position); View view; ViewHolder viewHolder; if (convertView == null) { view = LayoutInflater.from(getContext()).inflate(resourceId, null); viewHolder=new ViewHolder(); viewHolder.icon= (ImageView) view.findViewById(R.id.item_icon); viewHolder.title= (TextView) view.findViewById(R.id.item_title); viewHolder.description= (TextView) view.findViewById(R.id.item_description); viewHolder.time= (TextView) view.findViewById(R.id.item_time); view.setTag(viewHolder); } else { view = convertView; viewHolder= (ViewHolder) view.getTag(); } viewHolder.icon.setImageResource(item.getResId()); viewHolder.title.setText(item.getTitle()); viewHolder.description.setText(item.getDescription()); viewHolder.time.setText(item.getTime()); return view; } class ViewHolder{ ImageView icon; TextView title; TextView description; TextView time; } }
Activity的代码
package cn.edu.zafu.myapplication; import android.os.Bundle; import android.support.v7.app.ActionBarActivity; import android.view.View; import android.widget.AdapterView; import android.widget.ListView; import android.widget.Toast; import java.util.ArrayList; import java.util.List; public class MainActivity extends ActionBarActivity { private List<Item> items=new ArrayList<Item>(); @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); initMenus();//初始化数据 MyArrayAdapter adapter=new MyArrayAdapter(this,R.layout.item_layout,items);//新建自己的适配器 ListView listView= (ListView)findViewById(R.id.listview); listView.setAdapter(adapter);//设置适配器 listView.setOnItemClickListener(new AdapterView.OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { Item item=items.get(position);//获得点击项对应实体类 Toast.makeText(getApplicationContext(),item.getTitle(),Toast.LENGTH_SHORT).show(); } }); } //数据初始化 private void initMenus() { Item train=new Item(R.drawable.car,"ECMobile","蓝天神鹰","下午1:15"); items.add(train); Item road=new Item(R.drawable.car,"YiiBook讨论群","UM5","下午2:23"); items.add(road); Item history=new Item(R.drawable.car,"腾讯新闻","上海踩踏事件伤者惊魂","下午12:15"); items.add(history); } }
在实现的过程中主要遇到两个问题
第一个是ListView最下面的一项的横线不见了,解决方法是将ListViewd layout_height设为match_parent而不是wrap_content
第二是设置了子项的高度后不起作用,解决方法是设置layout_height属性为wrap_content,增加minHeight属性即此文中的minHeight="60dp"
时间: 2024-10-28 21:11:42