private static boolean isThisASystemPackage(Context context, PackageInfo  packageInfo ) {
        try {
            PackageInfo sys = context.getPackageManager().getPackageInfo("android", PackageManager.GET_SIGNATURES);
            return (packageInfo != null && packageInfo.signatures != null &&
                    sys.signatures[0].equals(packageInfo.signatures[0]));
        } catch (NameNotFoundException e) {
            return false;
        }
    }

下面是获取Android上安装的活动/应用程序列表的代码:

Intent mainIntent = new Intent(Intent.ACTION_MAIN, null);
mainIntent.addCategory(Intent.CATEGORY_LAUNCHER);
List<ResolveInfo> pkgAppsList = context.getPackageManager().queryIntentActivities( mainIntent, 0);

您将在ResolveInfo中获得启动应用程序所需的所有数据。你可以在这里检查ResolveInfo javadoc。

下面是使用PackageManager的一种更简洁的方式

final PackageManager pm = getPackageManager();
//get a list of installed apps.
List<ApplicationInfo> packages = pm.getInstalledApplications(PackageManager.GET_META_DATA);

for (ApplicationInfo packageInfo : packages) {
    Log.d(TAG, "Installed package :" + packageInfo.packageName);
    Log.d(TAG, "Source dir : " + packageInfo.sourceDir);
    Log.d(TAG, "Launch Activity :" + pm.getLaunchIntentForPackage(packageInfo.packageName)); 
}
// the getLaunchIntentForPackage returns an intent that you can use with startActivity() 

更多信息请点击这里http://qtcstation.com/2011/02/how-to-launch-another-app-from-your-app/

要获得所有已安装的应用程序，您可以使用包管理器

List<PackageInfo> apps = getPackageManager().getInstalledPackages(0);

要运行一个应用程序，你可以使用它的包名

Intent launchApp = getPackageManager().getLaunchIntentForPackage(“package name”)
startActivity(launchApp);

欲了解更多细节，请阅读这个博客http://codebucket.co.in/android-get-list-of-all-installed-apps/

如果在一个包中有多个启动器，上述代码就有问题。例如:在LG Optimus Facebook为LG, MySpace为LG, Twitter为LG包含在一个包的名称SNS，如果你使用上述SNS将重复。经过几个小时的研究，我得到了以下代码。看起来效果不错。

private List<String> getInstalledComponentList()
            throws NameNotFoundException {
        final Intent mainIntent = new Intent(Intent.ACTION_MAIN, null);
        mainIntent.addCategory(Intent.CATEGORY_LAUNCHER);
        List<ResolveInfo> ril = getPackageManager().queryIntentActivities(mainIntent, 0);
        List<String> componentList = new ArrayList<String>();
        String name = null;

        for (ResolveInfo ri : ril) {
            if (ri.activityInfo != null) {
                Resources res = getPackageManager().getResourcesForApplication(ri.activityInfo.applicationInfo);
                if (ri.activityInfo.labelRes != 0) {
                    name = res.getString(ri.activityInfo.labelRes);
                } else {
                    name = ri.activityInfo.applicationInfo.loadLabel(
                            getPackageManager()).toString();
                }
                componentList.add(name);
            }
        }
        return componentList;
    }

过滤基于系统的应用程序:

private boolean isSystemPackage(ResolveInfo ri) {
    return (ri.activityInfo.applicationInfo.flags & ApplicationInfo.FLAG_SYSTEM) != 0;
}