PackageManager用法

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

java code

    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); 
        } 
    } 

xml code
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>