列表的显示需要三个元素:
1.ListVeiw:用来展示列表的View。
2.适配器:用来把数据映射到ListView上的中介。
3.数据:具体的将被映射的字符串,图片,或者基本组件。
下面用一个实例说明:
1.ListVeiw
Java中:
private ListView lvSearchReasult;
lvSearchReasult = (ListView) findViewById(R.id.lv_search_list);
Xml中:
<ListView
android:id="@+id/lv_search_list"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:divider="@color/item_focuse"
android:dividerHeight="0.1dp" >
</ListView>
2.适配器
适配器的设置:
SearchResultListAdapter adapter = new SearchResultListAdapter(listSearchResult, MainActivity.this);
lvSearchReasult.setAdapter(adapter);
适配器的定义:
Java:
public class SearchResultListAdapter extends BaseAdapter {
private List<Music> list;
private Context context;
public SearchResultListAdapter(List<Music> list, Context c) {
super();
this.list = list;
this.context = c;
}
@Override
public int getCount() {
return list.size();
}
@Override
public Object getItem(int position) {
return list.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder = null;
holder = new ViewHolder();
if (convertView == null) {
convertView = View.inflate(context,
R.layout.item_online_search_list, null);
holder.tvMusicName = (TextView) convertView
.findViewById(R.id.tv_search_list_title);
holder.tvMusicAritist = (TextView) convertView
.findViewById(R.id.tv_search_list_airtist);
holder.ivMusicImage = (ImageView) convertView
.findViewById(R.id.iv_search_list);
convertView.setTag(holder); //区分不同的convertView
} else {
holder = (ViewHolder) convertView.getTag();
}
Music music = list.get(position);
holder.tvMusicName.setText(music.getMusciName());
holder.tvMusicAritist.setText(music.getAirtistName());
ImageUtils.disPlay(music.getSmallAlumUrl(), holder.ivMusicImage,
R.drawable.icon_orange);
return convertView;
}
class ViewHolder {
TextView tvMusicName, tvMusicAritist;
ImageView ivMusicImage;
}
}
XML:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
style="@style/list_padding"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@drawable/selector_ltem" >
<ImageView
android:id="@+id/iv_search_list"
android:layout_width="44dp"
android:layout_height="44dp"
android:layout_centerVertical="true"
android:scaleType="centerCrop"
android:src="@drawable/icon_orange"
tools:ignore="ContentDescription" />
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="44dp"
android:layout_marginLeft="4dp"
android:layout_toRightOf="@+id/iv_search_list"
tools:ignore="RtlHardcoded" >
<TextView
android:id="@+id/tv_search_list_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:singleLine="true"
android:text="随他吧"
android:textColor="@color/black"
android:textSize="@dimen/txt_size_title"
tools:ignore="HardcodedText" />
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:orientation="horizontal" >
<TextView
android:layout_width="24dp"
android:layout_height="12dp"
android:layout_gravity="center_vertical"
android:layout_marginLeft="4dp"
android:background="@color/main_orange"
android:gravity="center"
android:singleLine="true"
android:text="H Q"
android:textColor="@color/white"
android:textSize="8sp"
android:textStyle="bold"
tools:ignore="HardcodedText,SmallSp" />
<TextView
android:id="@+id/tv_search_list_airtist"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="4dp"
android:gravity="center"
android:singleLine="true"
android:text="胡维纳"
android:textColor="@color/gray_deep"
android:textSize="14sp"
tools:ignore="HardcodedText" />
</LinearLayout>
</RelativeLayout>
<ImageView
android:layout_width="40dp"
android:layout_height="40dp"
android:layout_alignParentRight="true"
android:layout_centerVertical="true"
android:background="@drawable/icon_more"
tools:ignore="ContentDescription,RtlHardcoded" />
该XML文件配置的时候列表每一行的布局,适配器会将得到的数据按照这样的布局以前面设置好的Textview格式一行一行显示在UI上。
3.数据
数据通常情况是一个数组,适配器会将其中的每一项按照规定的布局显示在UI中。