（PackageManager）信息类

• 类图结构

                            

• Android.content.pm包
• ApplicationInfo  
• ComponentInfo
  •  ActivityInfo
  • ProviderInfo
  • ServiceInfo
• InstrumentationInfo
• PermissionGroupInfo
• PermissionInfo

•  PackageInfo 
•  ResolveInfo  

•  用例
  • ApplicationInfo
  • ResolveInfo
  •  PackageInfo

public class MainActivity extends Activity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		
		//获取包名PackageManager	PackageInfo	ApplicationInfo	ActivityInfo
		
		//获取包管理器
		PackageManager pm=this.getPackageManager();
		
		//获取所有的包信息
		List<PackageInfo> packageInfos=pm.getInstalledPackages(PackageManager.GET_UNINSTALLED_PACKAGES);
		
		for (PackageInfo packageInfo : packageInfos) {
			
			//获取应用程序信息(<application>标签)
			ApplicationInfo applicationInfo=packageInfo.applicationInfo;
		
			//应用程序包名
			Log.i("liujun", "PackageInfo包名：---"+applicationInfo.packageName);
			
		}
		
		
		//////////////////////////////////////////////////////////////////////
		
		//创建意图
		Intent intent=new Intent();
		intent.setAction(Intent.ACTION_MAIN);
		intent.addCategory(Intent.CATEGORY_LAUNCHER);
		
		//获取解析信息对象集合
		List<ResolveInfo> resolveInfos=pm.queryIntentActivities(intent, PackageManager.MATCH_DEFAULT_ONLY);
		
		for (ResolveInfo resolveInfo : resolveInfos) {
			
			//获取应用程序包名
			String packName=resolveInfo.activityInfo.packageName;
			
			Log.i("liujun", "ResolveInfo包名：--"+packName);
			
		}
		
		
		Log.i("liujun", "packageInfos长度：--"+packageInfos.size());
		
		Log.i("liujun", "ResolveInfo长度：--"+resolveInfos.size());
		
		
		/**
		 *	结果表明packageInfos.size()会多于resolveInfos.size()的
		 *	这是因为PackageInfo代表的是整个系统安装的程序（包）
		 *	ResolveInfo代表的是整个系统中含有桌面快捷图标的程序
		 * 	显然前者包含后者，且多于后者
		 */
		
	}

}

代码地址

http://download.csdn.net/detail/u010739551/7893685

补充 

RunningTaskInfo

        ActivityManager mActivityManager = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
        
        //当前运行的任务栈信息集合
        List<RunningTaskInfo> rti = mActivityManager.getRunningTasks(1);
        
        RunningTaskInfo runningTaskInfo=rti.get(0);
        
        //组件名
        ComponentName componentName=runningTaskInfo.topActivity;
        
        //包名
        String packageNameStr=componentName.getPackageName();

PackageManager