Android BaseAdapter 例子

本文主要是介绍Android BaseAdapter 例子，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

Java代码

public class RecentAdapter extends BaseAdapter {

 private class RecentViewHolder {
  TextView appName;
  ImageView appIcon;
  TextView appSize;
 }

 private List<ResolveInfo> mAppList;
 private LayoutInflater mInflater;
 private PackageManager pm;

 public RecentAdapter(Context c, List<ResolveInfo> appList,
   PackageManager pm) {
  mAppList = appList;
  this.pm = pm;
  mInflater = (LayoutInflater) c
    .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
 }
 
 public void clear(){
  if(mAppList!=null){
   mAppList.clear();
  }
 }

 public int getCount() {
  return mAppList.size();
 }

 @Override
 public Object getItem(int position) {
  return mAppList.get(position);
 }

 @Override
 public long getItemId(int position) {
  // TODO Auto-generated method stub
  return position;
 }

 public View getView(int position, View convertView, ViewGroup parent) {
  RecentViewHolder holder;
  if (convertView == null) {
   convertView = mInflater.inflate(R.layout.app_info_item, null);
   holder = new RecentViewHolder();
   holder.appName = (TextView) convertView.findViewById(R.id.app_name);
   holder.appIcon = (ImageView) convertView
     .findViewById(R.id.app_icon);
   holder.appSize = (TextView) convertView.findViewById(R.id.app_size);
   convertView.setTag(holder);
  } else {
   holder = (RecentViewHolder) convertView.getTag();
  }
  ResolveInfo appInfo = mAppList.get(position);
  if (appInfo != null) {
   String labelName = appInfo.loadLabel(pm).toString();
   if (labelName != null) {
    holder.appName.setText(labelName);
   }

   Drawable icon = appInfo.loadIcon(pm);
   if (icon != null) {
    holder.appIcon.setImageDrawable(icon);
   }
  }
  return convertView;
 }
 
 public void remove(int position){
  mAppList.remove(position);
  this.notifyDataSetChanged();
 }

}

 

其中两个注意点为：

setTag 用View设置存储数据

notifyDataSetChanged() 告诉View数据更改并刷新

View convertView = mInflater.inflate(R.layout.app_info_item, null)  加载XML Item 示图

 

app_info_item.xml文件示例

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:layout_width="fill_parent" android:layout_height="wrap_content"
 android:layout_gravity="center_vertical" android:minHeight="?android:attr/listPreferredItemHeight">

 <ImageView android:id="@+id/app_icon" android:layout_width="@android:dimen/app_icon_size"
  android:layout_height="@android:dimen/app_icon_size"
  android:layout_alignParentLeft="true" android:paddingLeft="6dip"
  android:paddingTop="6dip" android:paddingBottom="6dip"
  android:scaleType="fitCenter" />

 <TextView android:id="@+id/app_name" android:layout_width="wrap_content"
  android:layout_height="wrap_content" android:textAppearance="?android:attr/textAppearanceLarge"
  android:textColor="?android:attr/textColorPrimary"
  android:layout_toRightOf="@id/app_icon" android:paddingLeft="6dip"
  android:paddingTop="6dip" />

 <TextView android:id="@+id/app_description"
  android:layout_width="wrap_content" android:layout_height="wrap_content"
  android:textAppearance="?android:attr/textAppearanceSmall"
  android:layout_below="@+id/app_name" android:layout_toRightOf="@id/app_icon"
  android:paddingLeft="6dip" android:paddingBottom="6dip" />
 <TextView android:id="@+id/app_size" android:layout_width="wrap_content"
  android:layout_height="wrap_content" android:textAppearance="?android:attr/textAppearanceSmall"
  android:layout_alignParentRight="true" android:layout_below="@+id/app_name"
  android:paddingRight="6dip" android:maxLines="1" />

</RelativeLayout>

 

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