Android杂谈--获取系统及应用程序(PackageManager)

PackageManager是个非常好的东西，其他的详细的细节等日后有时间整理

PackageManager的功能：

•安装，卸载应用
•查询permission相关信息
•查询Application相关信息(application，activity，receiver，service，provider及相应属性等）
•查询已安装应用
•增加，删除permission
•清除用户数据、缓存，代码段等

 

我们可以用PackageManager来显示系统安装的应用程序列表或者系统程序列表

废话先不多说

 

AppShowActivity.java

package com.loulijun.appshow;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import android.app.Activity;
import android.content.Context;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.TextView;

public class AppShowActivity extends Activity {
    ListView lv;
    MyAdapter adapter;
    ArrayList<HashMap<String, Object>> items = new ArrayList<HashMap<String, Object>>();
    
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        lv = (ListView)findViewById(R.id.lv);
        //得到PackageManager对象
        PackageManager pm = getPackageManager();
        //得到系统安装的所有程序包的PackageInfo对象
        //List<ApplicationInfo> packs = pm.getInstalledApplications(0);
        List<PackageInfo> packs = pm.getInstalledPackages(0);
        
        for(PackageInfo pi:packs)
        {
        	HashMap<String, Object> map = new HashMap<String, Object>();
        	//显示用户安装的应用程序，而不显示系统程序
//        	if((pi.applicationInfo.flags&ApplicationInfo.FLAG_SYSTEM)==0&&
//        			(pi.applicationInfo.flags&ApplicationInfo.FLAG_UPDATED_SYSTEM_APP)==0)
//        	{
//        		//这将会显示所有安装的应用程序，包括系统应用程序
//            	map.put("icon", pi.applicationInfo.loadIcon(pm));//图标
//            	map.put("appName", pi.applicationInfo.loadLabel(pm));//应用程序名称
//            	map.put("packageName", pi.applicationInfo.packageName);//应用程序包名
//            	//循环读取并存到HashMap中，再增加到ArrayList上，一个HashMap就是一项
//            	items.add(map);
//        	}
        	//这将会显示所有安装的应用程序，包括系统应用程序
        	map.put("icon", pi.applicationInfo.loadIcon(pm));//图标
        	map.put("appName", pi.applicationInfo.loadLabel(pm));//应用程序名称
        	map.put("packageName", pi.applicationInfo.packageName);//应用程序包名
        	//循环读取并存到HashMap中，再增加到ArrayList上，一个HashMap就是一项
        	items.add(map);
        }
        /**
         * 参数：Context
         * ArrayList(item的集合)
         * item的layout
         * 包含ArrayList中的HashMap的key的数组
         * key所对应的值的相应的控件id
         */
        adapter = new MyAdapter(this, items, R.layout.piitem, 
        		new String[]{"icon", "appName", "packageName"},
        		new int[]{R.id.icon, R.id.appName, R.id.packageName});
        lv.setAdapter(adapter);
    }
}

class MyAdapter extends SimpleAdapter
{
	private int[] appTo;
	private String[] appFrom;
	private ViewBinder appViewBinder;
	private List<? extends Map<String, ?>>  appData;
	private int appResource;
	private LayoutInflater appInflater;
	
	public MyAdapter(Context context, List<? extends Map<String, ?>> data,
			int resource, String[] from, int[] to) {
		super(context, data, resource, from, to);
		appData = data;
		appResource = resource;
		appFrom = from;
		appTo = to;
		appInflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
	}
	
	public View getView(int position, View convertView, ViewGroup parent)
	{
		return createViewFromResource(position, convertView, parent, appResource);
		
	}
	
	private View createViewFromResource(int position, View convertView, ViewGroup parent, int resource)
	{
		View v;
		if(convertView == null)
		{
			v = appInflater.inflate(resource, parent,false);
			final int[] to = appTo;
			final int count = to.length;
			final View[] holder = new View[count];
			
			for(int i = 0; i < count; i++)
			{
				holder[i] = v.findViewById(to[i]);
			}
			v.setTag(holder);
		}else
		{
			v = convertView;
		}
		bindView(position, v);
		return v;	
	}
	
	private void bindView(int position, View view)
	{
		final Map dataSet = appData.get(position);
		if(dataSet == null)
		{
			return;
		}
		
		final ViewBinder binder = appViewBinder;
		final View[] holder = (View[])view.getTag();
		final String[] from = appFrom;
		final int[] to = appTo;
		final int count = to.length;
		
		for(int i = 0; i < count; i++)
		{
			final View v = holder[i];
			if(v != null)
			{
				final Object data = dataSet.get(from[i]);
				String text = data == null ? "":data.toString();
				if(text == null)
				{
					text = "";
				}
				
				boolean bound = false;
				if(binder != null)
				{
					bound = binder.setViewValue(v, data, text);
				}
				
				if(!bound)
				{
					/**
					 * 自定义适配器，关在在这里，根据传递过来的控件以及值的数据类型，
					 * 执行相应的方法，可以根据自己需要自行添加if语句。另外，CheckBox等
					 * 集成自TextView的控件也会被识别成TextView，这就需要判断值的类型
					 */
					if(v instanceof TextView)
					{
						//如果是TextView控件，则调用SimpleAdapter自带的方法，设置文本
						setViewText((TextView)v, text);
					}else if(v instanceof ImageView)
					{
						//如果是ImageView控件，调用自己写的方法，设置图片
						setViewImage((ImageView)v, (Drawable)data);
					}else
					{
						throw new IllegalStateException(v.getClass().getName() + " is not a " +
								"view that can be bounds by this SimpleAdapter");
					}
				}
			}
		}
	}
	public void setViewImage(ImageView v, Drawable value)
	{
		v.setImageDrawable(value);
	}
}

 main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
	android:orientation="vertical" android:layout_width="fill_parent"
	android:layout_height="fill_parent">
	<ListView android:id="@+id/lv" android:layout_width="fill_parent"
		android:layout_height="fill_parent">
	</ListView>
</LinearLayout>

 

piitem.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
	android:orientation="horizontal" android:layout_width="fill_parent"
	android:layout_height="fill_parent">
	<ImageView android:id="@+id/icon" android:layout_width="48dip"
		android:layout_height="48dip" />
	<LinearLayout android:orientation="vertical"
		android:layout_width="fill_parent" android:layout_height="wrap_content">
		<TextView android:id="@+id/appName" android:layout_width="fill_parent" android:layout_height="wrap_content"/>
		<TextView android:id="@+id/packageName" android:layout_width="fill_parent" android:layout_height="wrap_content"/>
	</LinearLayout>
</LinearLayout>

 现在看看效果图

如果要只是显示用户安装的应用程序的话，可以直接使用

如果用户要显示包括系统程序的话，需要取出if的判断部分，上面代码里面有标识